12512398-REP Final Draft REF Burrendong Deep Storage Access · Burrendong Dam Deep Water Storage (referred to as the ‘proposal’) to supply water to communities that rely on surface

WaterNSW Burrendong Dam Deep Water Storage Access

Review of Environmental Factors November 2019

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Executive summary WaterNSW is Australia’s largest supplier of raw water, delivering water from 42 dams, state rivers and pipelines to NSW irrigators, licenced authorities, retail suppliers and councils. WaterNSW develops infrastructure solutions to ensure water supply security.

WaterNSW operates and maintains dams, weirs and ancillary structures across the Macquarie Valley system in western NSW to deliver water to customers. WaterNSW also works with the Department of Planning, Industry and Environment (DPIE) to assess drought conditions including relating to water allocations to licence holders.

The Macquarie River Catchment is regulated and includes cities and towns such as Dubbo, Wellington, Narromine, Warren, Nyngan and Cobar. The main water storages in the catchment are Burrendong Dam, on the Macquarie River upstream of Wellington, and Windamere Dam, on the Cudgegong River upstream of Mudgee.

Due to the current drought, inflows to Burrendong Dam between May 2017 – April 2019 are 38% of the previous drought of record. The catchment area is classified as being in a Stage 4 drought – critical drought with storage levels at 4% of capacity on 1 October 2019. The Macquarie River is projected to cease to flow downstream of Burrendong Dam in January 2020 if there are no inflows and in the absence of further drought response works. As a result of the current drought conditions, the relevant water sharing plan for the Macquarie and Cudgegong Regulated River has been partly suspended under the Water Management Act 2000 to prioritise water for critical human water needs.

WaterNSW, local water utilities (Councils) and DPIE are jointly and individually planning to implement a range of projects and actions in stages to provide emergency water supplies to affected communities under Stage 4 drought conditions. This includes creating access to Burrendong Dam Deep Water Storage (referred to as the ‘proposal’) to supply water to communities that rely on surface water delivered from Burrendong Dam.

WaterNSW would notify the Minister for Fisheries in accordance with section 199 of the Fisheries Management Act 1994. Operational impacts would be monitored by implementing water quality and fish ecology monitoring plans that would be developed in consultation with DPIE-Water, DPIE and the Department of Primary Industry – Fisheries (DPIF).

The REF assesses the potential impacts of the proposal. It has been prepared in accordance with Part 5 of the Environmental Planning and Assessment Act 1979 (‘EP&A Act’) and considers the factors listed in clause 228 of the associated Regulation. This REF documents the potential environmental impacts of the proposal, considering both potential positive and negative impacts and recommends management and mitigation measures to protect the environment.

Overall, potential negative impacts associated with the proposal can be adequately managed by implementing mitigation measures, and the beneficial impacts are considered to outweigh the adverse impacts. For the reasons described in this report, the proposal is unlikely to have a significant impact on the environment and does not require an EIS to be prepared, or a referral to the Commonwealth under the Environment Protection and Biodiversity Conservation Act (EPBC Act).

If the proposal assessed in this REF changes, WaterNSW would determine whether additional environmental assessment is needed to ensure that their obligations under the EP&A Act are addressed.

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Table of contents 1. Introduction ................................................................................................................................... 1

1.1 Background .......................................................................................................................... 1

1.2 Overview of the proposal .................................................................................................... 4

1.3 Purpose of this report .......................................................................................................... 4

1.4 Limitations ........................................................................................................................... 5

2. Proposal need and alternatives ..................................................................................................... 6

2.1 Need for the proposal .......................................................................................................... 6

2.2 Water security options ...................................................................................................... 11

2.3 Justification for the preferred option ................................................................................ 16

3. Description of the proposal ......................................................................................................... 17

3.1 Location ............................................................................................................................. 17

3.2 Overview ............................................................................................................................ 19

3.3 Construction ...................................................................................................................... 26

3.4 Operation ........................................................................................................................... 29

3.5 Decommissioning ............................................................................................................... 30

4. Planning context .......................................................................................................................... 32

4.1 Environmental Planning and Assessment Act 1979 .......................................................... 32

4.2 Commonwealth legislation ................................................................................................ 34

4.3 NSW legislation .................................................................................................................. 37

5. Consultation ................................................................................................................................. 41

5.1 Community and stakeholder engagement plan ................................................................ 41

5.2 Consultation relating to this REF ....................................................................................... 43

5.3 Future consultation ........................................................................................................... 47

6. Environmental impact assessment .............................................................................................. 48

6.1 Land use ............................................................................................................................. 48

6.2 Traffic and access ............................................................................................................... 49

6.3 Hydrology and water quality ............................................................................................. 50

6.4 Aquatic biodiversity ........................................................................................................... 59

6.5 Terrestrial biodiversity ....................................................................................................... 66

6.6 Topography, geology and soils .......................................................................................... 73

6.7 Aboriginal heritage ............................................................................................................ 75

6.8 Historic heritage ................................................................................................................ 77

6.9 Socio-economic .................................................................................................................. 79

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6.10 Air quality ........................................................................................................................... 81

6.11 Noise and vibration ............................................................................................................ 82

6.12 Visual amenity ................................................................................................................... 98

6.13 Waste, contamination and resource minimisation ........................................................... 99

6.14 Cumulative impacts ......................................................................................................... 101

7. Environmental management ..................................................................................................... 103

7.1 Construction environmental management plan ............................................................. 103

7.2 Operational environmental management ....................................................................... 103

8. Conclusion .................................................................................................................................. 104

8.1 Justification of the proposal ............................................................................................ 104

8.2 Principles of ecological sustainable development ........................................................... 105

8.3 Conclusion ....................................................................................................................... 107

9. References ................................................................................................................................. 108

Table index Table 2-1 Water Management Act take priority under s 60(3A) and section 49B order .................... 7

Table 2-2 Determining the stage of criticality for water quantity extreme events (source: WaterNSW ........................................................................................................................... 9

Table 2-3 Stages of the Incident Response guide (IRG) framework (source: WaterNSW) ................ 10

Table 3-1 Project site land details ..................................................................................................... 17

Table 3-2 Summary of dam water and outlet levels and required dam/outlet ................................ 21

Table 4-1 EPBC protected matters search results ............................................................................. 35

Table 5-1 Key stakeholders ................................................................................................................ 41

Table 5-2 Summary of stakeholder communication and engagement activities undertaken ........................................................................................................................ 43

Table 5-3 Summary of consultation responses ................................................................................. 45

Table 6-1 Land use mitigation measures ........................................................................................... 48

Table 6-2 Traffic and access mitigation measures ............................................................................. 49

Table 6-3 In situ water quality results, 28 August 2019 .................................................................... 53

Table 6-4 Results of laboratory analysis of samples collected 28 August 2019 ................................ 54

Table 6-5 Hydrology and water quality mitigation measures ........................................................... 58

Table 6-6 Burrendong Dam Photos and habitat observations, 28 August 2019 ............................... 59

Table 6-7 Mitigation measures for potential impacts on aquatic ecology ........................................ 65

Table 6-8 Summary of fauna species with moderate to high likelihood of occurrence within the proposal site ..................................................................................................... 68

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Table 6-9 Weed species previously recorded in the locality ............................................................. 69

Table 6-10 Key threatening processes ................................................................................................. 72

Table 6-11 Proposed mitigation measures .......................................................................................... 73

Table 6-12 Topography, geology and soil mitigation measures .......................................................... 74

Table 6-13 Aboriginal heritage mitigation measures .......................................................................... 77

Table 6-14 Historic Heritage mitigation measures .............................................................................. 79

Table 6-15 Socio-economic mitigation measures ............................................................................... 80

Table 6-16 Air quality mitigation measures ......................................................................................... 81

Table 6-17 Identified sensitive receivers ............................................................................................. 84

Table 6-18 Recommended RBL ............................................................................................................ 84

Table 6-19 ICNG CNMLs at identified receivers, dB(A) ........................................................................ 85

Table 6-20 Noise Policy for Industry (NPI) Project noise trigger levels ............................................... 86

Table 6-21 Road traffic noise criteria, LAeq(period), dB(A) ........................................................................ 87

Table 6-22 Guidance on effects of vibration levels ............................................................................. 88

Table 6-23 Transient vibration guide for cosmetic damage (BS 7385:1993) ...................................... 88

Table 6-24 Guideline values for short term vibration on structures (DIN 4150-3) ............................ 89

Table 6-25 Guideline values for vibration effects on buried pipework ............................................... 89

Table 6-26 Construction equipment sound power levels ................................................................... 90

Table 6-27 Noise impact distances ...................................................................................................... 92

Table 6-28 General Operational Noise Model Inputs and Assumptions ............................................. 93

Table 6-29 Operational noise sources ................................................................................................. 94

Table 6-30 Predicted operational noise impact .................................................................................. 94

Table 6-31 Vibration safe working distances ....................................................................................... 96

Table 6-32 Construction mitigation and management measures ....................................................... 96

Table 6-33 Additional management measures for construction activities out of standard hours. ................................................................................................................................. 97

Table 6-34 Sensitive receivers ............................................................................................................. 98

Table 6-35 Visual amenity mitigation measures ................................................................................. 99

Table 6-36 Waste, contamination and resource management mitigation measures ....................... 100

Figure index Figure 1-1 Macquarie River Catchment ................................................................................................ 2

Figure 1-2 Regulated river (High security) access licence holders in the Macquarie Valley ................ 3

Figure 1-3 WaterNSW staged works ..................................................................................................... 4

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Figure 2-1 Comparison of inflows to Burrendong Dam during droughts ............................................. 6

Figure 2-2 Map of incident response guide criticality levels of NSW inland river systems .................. 8

Figure 2-3 Short, medium and longer term supply strategies ............................................................ 11

Figure 2-4 Scenarios to defer a cease to flow event in the Macquarie River downstream from Burrendong Dam ....................................................................................................... 14

Figure 3-1 Burrendong Dam Location Map ........................................................................................ 18

Figure 3-2 Proposed aeration system ................................................................................................. 20

Figure 3-3 Sketch showing potential cofferdam embankment footprint ........................................... 22

Figure 3-4 Coffer dam cross section ................................................................................................... 23

Figure 3-5 Pumping system- floating pontoon with pumps ............................................................... 25

Figure 3-6 Proposal project area ........................................................................................................ 28

Figure 3-7 Anticipated surface area of the 20 GL deep storage compared to the 6 GL draw down level.......................................................................................................................... 31

Figure 6-1 Average annual rainfall in the Macquarie-Bogan catchment ............................................ 50

Figure 6-2 Mean daily evaporation for Wellington (BoM website) .................................................... 51

Figure 6-3 Vegetation communities ................................................................................................... 70

Figure 6-4 Previously recorded sites in relation to the study area ..................................................... 76

Figure 6-5 Project location and identified sensitive receivers ............................................................ 83

Appendices Appendix A – Water sharing plan suspension order

Appendix B – WaterNSW Community Media Release – June 2019 Operations Update

Appendix C – Clause 228 review

Appendix D – Water Quality and Aquatic Ecology Impact Assessment

Appendix E – Threatened biodiversity assessment

Appendix F – Aboriginal Due Diligence Assessment and Statement of Heritage Impact Report

Appendix G – Construction noise contours

Appendix H – DPI Fisheries – response to consultation under section 199 of the Fisheries Management Act 1994

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1. Introduction 1.1 Background

WaterNSW is Australia’s largest supplier of raw water, delivering water from 42 dams, state rivers and pipelines to NSW irrigators, licenced authorities, retail suppliers and councils. WaterNSW develops infrastructure solutions to ensure water supply security and contributes to the protection of the environment and catchments.

WaterNSW operates and maintains dams, weirs and ancillary structures across the Macquarie Valley system in western NSW to deliver water to customers. WaterNSW also works with the Department of Planning, Industry and Environment (DPIE) to assess drought conditions and determine whether it is necessary to reduce water allocations to licence holders.

The Macquarie River Catchment is regulated and includes cities and towns such as Dubbo, Wellington, Narromine, Warren, Nyngan and Cobar. The main water storages in the catchment are Burrendong Dam which is on the Macquarie River, upstream of Wellington, and Windamere Dam which is on the Cudgegong River upstream of Mudgee (refer to Figure 1-1). The Chifley and Winburndale dams are small storages located in upper Macquarie catchment. Figure 1-2 shows the high security water users in the Macquarie Valley which include major urban centres, permanent plantings, industry, and other uses such as the Western Plains Zoo at Dubbo. Due to the current drought, inflows to Burrendong Dam between May 2017 – April 2019 are 38% of the previous drought of record. On 1 October 2019, the water storage levels of the Burrendong Dam was at 4%. The Macquarie River system is classified as being in a Stage 4 drought – critical drought / water shortage in accordance with the NSW Extreme Events Policy – Incident Response Guide (IRG) and is currently being operated under drought contingency measures with water delivery restrictions. The drought conditions are having a severe effect on storages, the river system, towns, environment and rural water users. The Macquarie River is projected to cease to flow downstream of Burrendong Dam in November 2019 if there are no inflows to the system and in the absence of any drought contingency measures and drought response works.

WaterNSW, local water utilities (Councils) and DPIE are jointly and individually planning to implement, are implementing or have implemented a range of projects and actions to provide emergency water supplies to affected communities under the IRG Stage 4 drought conditions. This includes implementing temporary works to supply water to communities that rely on surface water delivered from Burrendong Dam, including Dubbo, Wellington, Nyngan and Cobar. The temporary works are being implemented in three stages as indicated in Figure 1-3 and Section 2.2.2. Macquarie Drought Response Project Stage 1 was completed in early September 2019 and involved raising Warren Weir and installing temporary structures to block flow at fishways on Crooked Creek, Duck Creek, Warren Weir, Gunningbar Creek and the Marebone regulator. Macquarie Drought Response Project Stage 2 involves a bulk water transfer from Windamere Dam to Burrendong Dam and is anticipated to occur in late 2019. Stage 3 is proposed to access the inactive or deep storage within reservoir held by Burrendong Dam, estimated to be approximately 21 GL that cannot be accessed using the existing outlet. WaterNSW proposes to commence construction of Macquarie Drought Response Project Stage 3 in October 2019 and commence operation by February 2020.


Figure 1-1 Macquarie River Catchment


Figure 1-2 Regulated river (High security) access licence holders in the Macquarie Valley


Figure 1-3 WaterNSW staged works

1.2 Overview of the proposal

WaterNSW proposes to implement drought response works (referred to as the ‘proposal’) at Burrendong Dam to access deep water storage that is below the level of the outlet (invert of tower bell-mouth). These works are described in section 3 and involve the following activities to supply water to the regulated river downstream:

Constructing a coffer dam to enable the water level to be raised around the outlet tower so it can be delivered to the Macquarie River via the existing outlet.

Aeration outside the area impounded by the coffer dam to minimise the risk of water in the depleted storage stratifying, resulting in anoxic water quality conditions developing while pumping water from the deep water section of the reservoir of Burrendong Dam to the waterbody formed by the coffer dam around the outlet tower. The deep storage would be drawn down until approximately 6 GL remains in the reservoir.

The proposal would be capable of commencing pumping by February 2020.

1.3 Purpose of this report

WaterNSW engaged GHD Pty Limited (GHD) to prepare this review of environmental factors (REF) to assess the potential environmental impacts of the construction and operation of the proposal. WaterNSW is the proponent and the determining authority for the proposal under Division 5.1 of Part 5 of the Environmental Planning and Assessment Act 1979 (EP&A Act).

The purpose of the REF is to describe the proposal, document the likely impacts of the proposal on the environment, and detail measures to mitigate impacts that cannot be avoided. The REF helps to fulfil the requirements of section 5.5 of the EP&A Act that WaterNSW examine and take into account to the fullest extent possible, all matters affecting or likely to affect the environment by reason of the activity.


The environmental impact assessment has been undertaken in context of clause 228 of the Environmental Planning and Assessment Regulation 2000, the Biodiversity Conservation Act 2016 (BC Act), the Fisheries Management Act 1994 (FM Act), and the Australian Government’s Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).

The findings of the REF would be considered when assessing:

Whether the proposal is likely to have a significant environmental impact and therefore the need for an environmental impact statement to be prepared and approval to be sought from the Minister for Planning and Industry under Part 5.1 of the EP&A Act

The significance of any impact on threatened species as defined by the BC Act and/or FM Act, in section 1.7 of the EP&A Act and therefore the requirement for a Species Impact Statement

The potential for the project to significantly impact a matter of national environmental significance or Commonwealth land and the need to make a referral to the Australian government Department of the Environment and Energy (DoEE) for a decision by the Commonwealth Minister for the Environment and Energy on whether approval is required under the EPBC Act.

1.4 Limitations

This report: has been prepared by GHD for WaterNSW and may only be used and relied on by WaterNSW for the purpose agreed between GHD and the WaterNSW as set out in this report.

GHD otherwise disclaims responsibility to any person other than WaterNSW arising in connection with this report. GHD also excludes implied warranties and conditions, to the extent legally permissible.

The services undertaken by GHD in connection with preparing this report were limited to those specifically detailed in the report and are subject to the scope limitations set out in the report.

The opinions, conclusions and any recommendations in this report are based on conditions encountered and information reviewed at the date of preparation of the report. GHD has no responsibility or obligation to update this report to account for events or changes occurring subsequent to the date that the report was prepared.

The opinions, conclusions and any recommendations in this report are based on assumptions made by GHD described in this report. GHD disclaims liability arising from any of the assumptions being incorrect.


2. Proposal need and alternatives 2.1 Need for the proposal

2.1.1 Effect of the drought on water supply in the Macquarie Valley

The current drought is having a severe impact on water storages in the Macquarie River valley. Figure 2-1 indicates that inflows to Burrendong Dam have been substantially lower during this drought compared to four previous droughts.

Figure 2-1 Comparison of inflows to Burrendong Dam during droughts

The total inflow to Burrendong Dam during the previous two worst years of drought (June 1979 – May 1981) was 258 GL. Compared to this, inflows between May 2017 – April 2019 were 99 GL which represents 38 % of the previous drought of record. The impact of these record low inflows on storage levels is shown in Figure 2-1. At 1 October 2019, storage in Burrendong Dam reservoir was at 4% capacity containing about 60 GL. Of the remaining storage, 40 GL is ‘active’ and is able to be accessed using the existing offtake infrastructure. The remaining 21 GL is inactive deep-water storage that is below the level of the existing offtake tower and not accessible.

The Drought Response Stage 1 was implemented in September 2019 and is expected to delay a cease to flow event until January 2020. The Macquarie River is predicted to cease to flow in January 2020 if there are no inflows to Burrendong Dam if there are no additional drought contingency measures and drought response works (stages 2 and 3).


2.1.2 Water operations

Macquarie-Castlereagh Incident Response Guide and prioritisation of supply

The NSW Extreme Events Policy introduces a staged approach to managing extreme events such as severe droughts or poor water quality events, and to the associated Incident Response Guides (IRGs).

Table 2-1 and Table 2-2 of the Macquarie–Castlereagh IRG state the priorities that apply to the distribution of water. The water allocations for higher priority licences are to be diminished at a lesser rate than the water allocations of lower priority licences. Table 2-2 of the IRG is repeated below in Table 2-1 and indicates that the first priority is to supply water for critical human water needs.

The water needs of the environment become the third priority under the WM Act section 60(3A) as parts of the Water Sharing Plan were suspended under an order made under s49B on 3 July 2019 (attached as Appendix A).

Table 2-1 Water Management Act take priority under s 60(3A) and section 49B order

Take type/use Priority

• The first priority is to be given to meeting critical human water needs. First

• The taking of water for domestic purposes by persons exercising basic landholder rights, and

• The taking of water for domestic purposes or essential town services authorised by an access licence.

Second

• Needs of the environment. Third

• The taking of water for stock purposes by persons exercising basic landholder rights, and

• In the case of regulated rivers, the taking of water for purposes (other than domestic purposes) authorised by a regulated river (high security) access licence, and

• The taking of water for the purposes of supply of commercial and industrial activities authorised by a major utility access licence or local water utility access licence, subject to the water made available being in accordance with any drought management strategy established by the Minister for that purpose, and

• The taking of water for the purposes of electricity generation authorised by a major utility access licence (not applicable in this WRPA), and

• The taking of water for purposes authorised by a domestic and stock access licence or by persons exercising any other water rights in relation to stock, and

• The taking of water for purposes authorised by a conveyance access licence in connection with the supply of water for any other purpose or need referred to in this paragraph (not applicable in this WRPA)

Fourth

• Taking of water for purposes authorised by any other category or subcategory of access licence.

Fifth


Note: In a case where orders under both sections 49A and 49B are in force in relation to the same water management area or

water source, the rules set out in WM Act s60 ss (3A) prevail.

The Macquarie regulated river water source has been in Stage 4 - Critical Drought /Water Shortage as defined under the Macquarie-Castlereagh IRG since May 2019 (https://www.industry.nsw.gov.au/water/allocations-availability/allocations/summary ). Stage 4 is the highest level under the IRG.

Critical human water needs means the needs for a minimum amount of water reasonably be provided from the Basin water resources, required to meet: (a) core human consumption requirements in urban and rural areas, and (b) those non-human consumption requirements that a failure to meet would cause prohibitively high social, economic or national security costs.

Figure 2-2 Map of incident response guide criticality levels of NSW inland river systems

https://www.industry.nsw.gov.au/water/allocations-availability/allocations/summary


Table 2-2 summarises factors that are considered when determining the criticality of an event under the IRG. Table 2-3 summarises the approaches under the Water Sharing Plan during each of the four stages. Under Critical drought Stage 4, some of the Water Sharing Plan operational rules may be suspended and contingency measures are adopted.

Table 2-2 Determining the stage of criticality for water quantity extreme events (source: WaterNSW


Table 2-3 Stages of the Incident Response guide (IRG) framework (source: WaterNSW)

Water Sharing Plan Part Suspension (Macquarie Regulated River) Order 2019

Given the severity of the drought, on 3 July 2019 the Minister for Water, Property and Housing gazetted the Water Sharing Plan Part Suspension (Macquarie Regulated River) Order 2019 under section 49B of the Water Management Act 2000. This order took effect on 1 July 2019 and suspends the operation of the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 with respect to planned environmental releases, available water determinations and water allocation account management in relation to the Macquarie Regulated River due to an extreme dry period. The concurrence of the NSW Minister for Energy and Environment was obtained before making this order.

Issuing an order to suspend part of a Water Sharing Plan is consistent with the approaches to manage risk in a Stage 4 critical drought / water shortage under the IRG. It also reflects that water is being prioritised for critical human water needs.


2.2 Water security options

WaterNSW, local water utilities (Councils) and DPIE-Water are jointly and individually planning to implement a range of projects and actions in stages to secure water supplies for critical human need given current Stage 4 - Critical Drought/Water Shortage. The measures are intended to extend the available water supply until there are substantial inflows to the Macquarie River system. Figure 2-3 summarises short, medium and longer term strategies that are being pursued.

Critical human need refers to the minimum amount of water needed to meet basic human needs. It also includes non-human needs, where a failure to meet these needs would cause too much damage to social, economic or national security (MDBA, 2019).

The following sections outline options that have been investigated to secure water supplies for critical human needs, including measures that have already been implemented.

Figure 2-3 Short, medium and longer term supply strategies

2.2.1 Do nothing option

The do-nothing option would mean not implementing the proposal and therefore not accessing the deep water storage. Water in the Burrendong Dam would be drawn down to 0% resulting in a cease to flow event for the Macquarie River. If there are no inflows to Burrendong Dam and no further drought contingency measures implemented, the Macquarie River would cease to flow downstream of the dam in January 2020 (refer to Figure 2-4).

If the river ceases to flow, WaterNSW would be unable to operate the system to deliver water to cities and towns downstream of Burrendong Dam, including Wellington, Dubbo, Warren, Nyngan and Cobar and this would result in significant human and socio-economic impacts across the Macquarie valley. Severe water restriction would be implemented that may impact on the feasibility of industrial, commercial, recreational and community facilities, including essential services, and this could potentially lead to evacuation.


The do-nothing option would also result in significant ecological impacts to the Macquarie valley. Following a cease to flow, water levels will decline and the river will revert to a series of pools that provide refugia habitat for aquatic biota. The extent and quality of aquatic habitat would progressively decline as the size of these pools diminishes due to evaporation, losses to groundwater and extraction for human needs. This would affect the full length of the Macquarie River downstream of Burrendong Dam, including the section between the dam and Warren, and has the potential to result in water quality impacts such as stratification, eutrophication and fish kills. It would affect refugia for native biota, including deep holes that provide habitat for threatened species. This cease to flow event would have the potential to result in impacts that include:

Complete loss of flowing habitat downstream of Burrendong Dam. This flowing habitat is the preferred habitat for the threatened Trout Cod and warming temperatures over summer could lead to mass fish kills.

Increased fish biomass in dwindling pools would lead to increased nutrient concentrations. This combined with still water due to the lack of flow will lead to cyanobacterial domination of the algal community. High cyanobacterial numbers in still water would cause stratification and the creation of an anoxic layer reducing oxygen levels for fish remaining and likely result in large scale fish kills of all species with the larger species dying first, as happened during January 2019 at the Darling River near Menindee Lakes. The decaying fish carcasses would release nutrients, allowing for an increase in the algal biomass and increasing oxygen demand on the pools at night, which may cause the death of the remaining fish.

Depending on how hot the 2019-20 summer is, the remaining refuge pools from Burrendong to Warren would have ideal conditions for cyanobacterial blooms and could result in the loss of native fish including large bodied species such as Murray Cod, Trout Cod, Golden Perch and Silver Perch as well as a range of small bodied fish along the Macquarie River.

Loss of habitat for terrestrial species.

Refuge pools too shallow to stratify would likely dry out over the summer with all fish and any other aquatic fauna trapped dying.

The do-nothing option would result in a critical water shortage as water would not be able to be delivered to meet the critical human water needs of cities and towns downstream of Burrendong Dam. It also has the potential to result in significant environmental impacts due to the large extent of the Macquarie River that would be affected by the cease to flow event. This is not a feasible option.

2.2.2 Temporary works to extend water supply within the Macquarie valley

The NSW Government has developed a three-stage strategy to delay a cease to flow event in the main channel of the Macquarie River downstream of Burrendong Dam that would occur under the do-nothing option. Macquarie Drought Response project Stage 1 involved temporary works to raise the level of the Warren Weir and this was completed in early September 2019. Macquarie Drought Response project Stage 2 involves transferring water from Windamere Dam to Burrendong Dam in December 2019. Stage 3 involves installing infrastructure to enable water to be pumped from the deep storage within Burrendong Dam from February 2020 (assessed in this REF).


Macquarie Drought Response project Stage 1 works are complete. Water will only flow past the Warren Weir, and Duck and Crooked Creek regulators if there are tributary flows into the Macquarie River downstream of Burrendong Dam. Water that would otherwise flow through the fishways at the weir and regulators is retained in the Warren weir pool to enable diversions to Nyngan and Cobar for town water supply. The Macquarie River ceased to flow below the Macquarie Marshes in December 2018 and in July 2019 the cease to flow point was in the southern Macquarie Marshes downstream of Warren. Macquarie Drought Response project Stage 1 will have an incremental adverse impact on an approximately 80 kilometre long section of the river downstream of Warren Weir, and Duck and Crooked Creek regulators which resulted in the cease to flow event being brought forward by two months.

Macquarie Drought Response Stage 1 works are extending the available water within approximately 314 kilometre long section of the Macquarie River between Burrendong Dam and Warren and will prolong the ability for fish to move between refuge habitats in the main channel of the river. Maintaining flow in the river also reduces the risk of adverse water quality conditions developing. This is a substantial environmental benefit compared to the do-nothing option.

Macquarie Drought Response Stage 2 does not require construction activity or environmental approval because bulk water transfers from Windamere Dam are an existing approved operational activity within the Water Sharing Plan for the Macquarie-Cudgegong Regulated Rivers. The transfer is planned for December 2019 and is anticipated to delay the cease to flow date by two months to March 2020.

Macquarie Drought Response Stage 3 is the subject of this REF, as described in Section 3 and is scheduled to commence operation following Stage 2 water transfer from Windamere Dam.

The combined effect of the three stages would be to extend the available water supply within the Macquarie system and delay the cease to flow event in the approximately ~314 kilometre long section of the river between Burrendong Dam and Warren from November 2019 to May 2020 if there are no inflows (refer to Figure 2-4). It would also reduce the volume of water stored in Burrendong Dam and this has the potential to have adverse impacts on aquatic biota and dependant terrestrial species.

All three stages need to be implemented to realise the benefits of deferring the cease to flow date. This is the preferred option.


Figure 2-4 Scenarios to defer a cease to flow event in the Macquarie River downstream from Burrendong Dam


2.2.3 Water delivery arrangements The severe and ongoing drought conditions across NSW are having a significant impact on the ability of WaterNSW to deliver water to users. While allocations for the Macquarie River system have been announced by the DPIE-W, the delivery of water is restricted due to the ongoing drought.

The Macquarie River system is being operated under drought contingency measures with water delivery restrictions and operational arrangements defined for each river section. The delivery restrictions and allocations are included in Appendix B.

This option is already being implemented and access to water in the 2019/2020 water year will be highly dependent on further inflows into the catchment and associated tributary inflows downstream from WaterNSW storages.

2.2.4 Alternative water sources

Carting water

Water carting is identified as a tolerable option when all other supplies fail. Water cartage from Dubbo to the villages within the LGA and the region around Dubbo forms a key component of the Regional Drought Management Plan for those smaller villages without a reticulated water supply (HydroScience Consulting 2015). Full water cartage to Dubbo City has been found to be impractical and very expensive. Water cartage to Nyngan and Cobar is considered unfeasible due to the cost and volume of water required.

Groundwater supplies

Dubbo and Narromine

Investigations have been undertaken to confirm the availability of groundwater sources to supplement water supplies to Dubbo and Narromine. The NSW Government has committed $30 million for Dubbo to expand its borefield and $2 million to allow Narromine to access groundwater (https://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-drought ).

Nyngan and Cobar

Nyngan and Cobar are challenged by the lack of reliable surface water sources. The original purpose of the Albert Priest Channel was to address the lack of reliable water sources at Nyngan by enabling water to be transferred to Nyngan from the Macquarie River, and construction of the pipeline from Nyngan to Cobar was justified for the same reason. Local groundwater typically has low productivity and high salinity.

There are no known viable groundwater sources within 100 kilometres of Cobar to provide an alternative supply. The groundwater within the Nyngan/Cobar area has a high salt content and is not considered adequate for human consumption without treatment. Treatment involving reverse osmosis for salt removal is a very expensive option and has not been considered as viable option to date.

Evacuation

Under extreme circumstances evacuation is a possible option for small populations. The social disruption of evacuation would be very difficult to manage for a large population (HydroScience Consulting 2011). If the do-nothing approach is adopted and there is no rainfall to replenish storages in the Macquarie valley, the decision to evacuate towns would need to be considered. As the cease to flow event approaches, water supplies could not be guaranteed. This would leave residents vulnerable to severe water shortages, and threatening the viability of the towns and Dubbo city.

https://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-drought

https://www.industry.nsw.gov.au/water/allocations-availability/droughts-floods/update/critical-valleys-in-drought


2.3 Justification for the preferred option

The proposal is justified because the Minister for Water has issued an order under section 49B of the Water Management Act 2000 to suspend part of the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 in respect to planned environmental releases, available water determinations and water allocation account management due to the extreme dry period. This reflects a NSW Government decision, with concurrence from the NSW Minister for Energy and Environment, that environmental releases are to cease and water is to be prioritised for critical human water needs. This prioritisation of water for critical human water needs is consistent with the intent of the Macquarie-Cudgegong IRG.

The proposal is also justified on an environmental basis because it would delay a cease to flow event in the approximately 314 kilometre long section of the main channel of the Macquarie River between Burrendong Dam and Warren. This will extend the duration that aquatic and terrestrial fauna are able to move between refuge habitat within the river and reduce the risk of adverse water quality conditions developing within the river. This is a beneficial impact compared to the do-nothing scenario, which is predicted to result in a cease to flow event in March 2020 that would affect the full length of the Macquarie River.

The proposal is designed to:

be cost effective by maximising the use of existing infrastructure and minimising the need to invest in new infrastructure.

enable it to be constructed and commissioned within a short timeframe in response to the current drought.

enable it to be decommissioned within a short timeframe in advance of significant inflows to Burrendong Dam.

minimise environmental impacts by limiting construction to existing disturbed areas and enabling dam releases to continue downstream. It will also reduce the length of the Macquarie River that is affected by a cease to flow event by about 314 kilometres compared to the do-nothing scenario.

The proposal will be constructed and operated in accordance with the requirements of DPIF arising from consultation in accordance with section 199 of the Fisheries Management Act 1994 (refer to Appendix H) Operational impacts would be monitored by implementing water quality and aquatic ecology monitoring plans that would be developed in consultation with DPIF and DPIE-W & DPIE-BC.

Overall, while there are potential negative impacts associated with the proposal, these are considered no worse than the do-nothing scenario and are able to be adequately managed by implementing the mitigation measures outlined in Section 6. The proposal is unlikely to have a significant impact on the environment and does not require an EIS or Species Impact Statement to be prepared under the NSW EP&A Act, and does not require a referral to the Commonwealth under the EPBC Act.

Details of the proposal’s location, objectives and design are provided in Section 3.


3. Description of the proposal 3.1 Location

Burrendong Dam is located south-east of Wellington, midway between Orange and Dubbo in Central West NSW. It is situated on the Macquarie River just below its confluence with the Cudgegong River, about 30 kilometres upstream from Wellington (refer Figure 3-1). Burrendong Dam is one of the largest inland dams in NSW with a storage capacity of 1,678,000 ML.

WaterNSW owns, operates and maintains the Burrendong Dam structures that the works would be undertaken on (refer Table 3-1).

Table 3-1 Project site land details

Name LGA Latitude Longitude Lot and DP

Zoning Land Ownership

Coffer dam, pumps and aeration system

Dubbo -32.66806 149.11124 Lot 32

DP 859391

E3- Environmental Management

WaterNSW / DPI Water

Site access and lay down areas

Dubbo -32.67012 149.10301 Lot 27

DP 756882



Quarry Dubbo -32.63984 149.11414 Lot 12

DP 750779



!

!

!

!

M

ITCHELLHIGHW

AY

RENSH

AWMC

GIRRWAY

BANJO

PATE

RSON

WAY

HILL

ENDROAD

TRIAMB

LEROAD

BURRENDONG DAM

ORANGE

DUBBO

WELLINGTON

FIGURE 3.1

0 4.5 9 13.5 18

Kilometres

Project No.Revision No. 0

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WaterNSWBurrendong Dam Deep Water Storage Analysis

Options Analysis Report

Map Projection: Mercator Auxiliary SphereHorizontal Datum: WGS 1984

Grid: WGS 1984 Web Mercator Auxiliary Sphere

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Legend

Burrendong Dam

Reservoir

Burrendong Dam Location Map

!

!

!

BURRENDONG DAMNEWCASTLE

CANBERRA

SYDNEY


3.2 Overview

3.2.1 Aeration / artificial circulation

The proposal to reduce the potential for stratification within the deep water storage includes the installation of an aeration system to circulate water and reduce the risk of water quality deterioration. This method is well established and has been used in the Sydney metropolitan dams to prevent or eliminate thermal stratification through the mixing action of a rising column of air bubbles for the last 25-30 years. A multi-criteria analysis was completed comparing surface aeration and fine bubble diffused aeration. Alignment with scope, sustainability, time, cost, safety and maintenance factors were considered. The fine bubble diffused air system scored significantly higher for environmental sustainability, water security (reduce risk of unsafe or potentially harmful water in waterways) and accessibility (on land or water) and ease of decommissioning. It is therefore proposed to install a fine bubble diffused air system. The system consists of air compressors, a manifold assembly, air supply and ballast pipes and a perforated air diffuser pipe. The air compressors would be housed in a small building above the dam’s maximum water level with associated equipment and pipework leading down and into the deep water storage (refer to Figure 3-2). The compressor building would be a pre-fabricated structure that is likely to have metal cladding and be sited on a concrete pad. The cladding colour would be selected to minimise visual impacts and this would be determined by WaterNSW during detailed design.

The compressed air would be discharged at depth with the long air diffuser pipe anchored within the deepest point of the deep water storage. The air flowrate would generate a water flow at the surface of about 30 to 45 m3/second. The aeration would mix water in the reservoir and movement of water to the surface would ensure that the oxygen in the air reaches the mixed water that is being displaced from depth.

Aeration would commence by November 2019 to reduce the likelihood of water quality deteriorating before pumping commences.

FIGURE 3.2

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Meters


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Water NSWBurrendong Dam Deep Water Storage Access

Review of Environmental Factors

THE C

IRCLE RO

ADCompressorbuilding

Line along topof outlet towerwalkway

Line down to groundlevel connectedto support foroutlet tower bridge

Deep wateraeration

Map Projection: Transverse MercatorHorizontal Datum: GDA 1994Grid: GDA 1994 MGA Zone 55

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Print date: 14 Nov 2019 - 16:22

Legend

Coffer Damembankment

Compressor building

Aeration line

Pontoons with pump

Proposed aeration system


3.2.2 Coffer Dam

The proposal involves constructing an earth and rock embankment to create a small basin around the outlet tower to hold water pumped from the lower deep storage within the reservoir enabling flow into the existing outlet structures via the offtake tower. The basin would hold water between 0.68 m and 1.4 m above the outlet invert to allow the existing outlet structure to be used to discharge flows of 80 – 300 ML/day. Relevant levels and assumptions used to determine the minimum height for the cofferdam are shown in Table 3-2.

Table 3-2 Summary of dam water and outlet levels and required dam/outlet

Feature Level or height

Outlet pipe invert level 311.2 m AHD

Minimum height of water (above outlet invert)

Adopted freeboard

0.82 m

0.5 m

Level of coffer dam base

Minimum level of dam crest

308.4 m AHD

312.52 m AHD

Minimum height of coffer dam 4.2 m (assume 4.5 m) – this will form a 4 m deep pool around the outlet

Based on levels and dimensions in Table 3-2, the coffer dam wall would be approximately 4.5 m high and 60 m long. A concept sketch of a coffer dam is shown in Figure 3-3 and Figure 3-4 shows a cross section of the coffer dam.

Since construction of Burrendong Dam the deposition of silt will have accumulated in the deep storage area and this may prevent water flowing to the pump offtake point. If this situation occurs, an excavator may be used to remove this silt and place it within the construction footprint, but above the water level. Removal of silt would be limited to the minimum volume required to enable water to continue to flow to the temporary pump offtake point.

FIGURE 3.3

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Meters


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Outlet tower


Deep waterstorage


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Legend


Coffer Dam footprint

Outlet tower

Deep water storage

Potential coffer damembankment and footprint

FIGURE 3.4


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Coffer dam cross section


Construction of the coffer dam would be staged to enable the water level in the dam to be maintained at an adequate level to allow discharges of up to 300 ML/day to be made during the construction period. The main steps in the construction process are as follows:

Step 1 – Installation of a silt curtain in the water to minimise potential water quality impacts associated with turbidity and ensure any residual construction debris remains in the immediate vicinity of the construction site.

Step 2 – Construction of the first half of the coffer dam that may include a culvert with penstock to allow flows post-construction. The second section of the dam would be open for flows to reach the outlet tower.

Step 3 – Construction of the second half of the coffer dam to complete the total width of the dam. The culvert and penstock would allow flows to the outlet towner to be maintained while the second half of the coffer dam is being constructed.

The coffer dam is likely to be constructed in the following steps:

Step 1 – Extraction of approximately 4,500 m3 of rock fill from allocated nearby quarry that was used to source material to construct Burrendong Dam.

Step 2 – Excavation of silt, and other sediment from the dam base for a suitably sized key in trench to prevent erosion of the dam foundation or under the low permeability liner.

Step 3 – Placement of a rock fill embankment approximately 60 metres long by five metres high.

Step 4 – Installation of a Geofabric liner over the length of the Downstream (Outlet tower) side of the coffer dam wall.

Step 5 – Once geofabric layers have been installed along the coffer dam wall batter, a liner would be installed on the coffer dam wall.

Step 6 – Once liner is installed on the entirety of the coffer dam wall, install a sand with no fines (or crushed rock) that is “self-compacting” on top of the liner material over the coffer dam wall batter slope.

Step 7 – Inspect liner during quality control phase of project to confirm that liner has been installed as per manufacturers recommendations.

3.2.3 Pumping system

The proposal involves installing a pump station and associated pipelines to displace the water in the deep water section of the Burrendong Dam (refer Figure 3-4). The pumping station is required to pump between 80 ML/day and 300 ML/day into the coffer dam. To provide the range of flow, six partially submerged pumps would be installed on two pre-fabricated pontoons each with their own length of between 100-150 metre pipeline. Single pumps are capable of reaching flows up to 600 L/s with two pumps running for the 80 ML/day duty and six pumps running for the 300 ML/day duty. The pontoons would be secured via a wire rope that is connected to a permanent support block (reinforced concrete anchor block a few metres elevation above current water level) that can be winched to if the pumps need to be removed due to rising water levels. Each pump intake will be fitted with screens to minimise potential impacts on aquatic biota. The type of screens to be installed would be determined during detailed design based on the outcome of consultation with, and endorsement from, DPI Fisheries. This would involve reviewing screening methods and determining suitability for this particular project.

FIGURE 3.5


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Pumping system –floating pontoon with pumps


Subject to constructability advice during detailed design, it may be necessary to install trench pipework between the deep storage and the pool formed by the coffer dam. The trenches would be excavated to the west of the coffer dam would be within areas that were disturbed during construction of the dam.

The existing high voltage power supply would be upgraded to enable the pumps to be powered by a connection to Essential Energy’s network. The high voltage works are assessed in a separate REF that will be determined by Essential Energy. A section of 11kV power line would be installed underground between the pad mounted substation and the switchroom at the compressor building.

3.3 Construction

3.3.1 Proposed construction equipment

The construction Contractor will select the construction plant and equipment to undertake the works and this is expected to include the following or similar:

Slew crane – 90 tonne

Long Reach Excavator – 40 tonne

Franna Crane – 20 tonne

Tip Trucks – 20 - 40 tonne

Dozers

Rock crusher and screen to separate fine material

Front end loader

Compactor

Excavator with hammer attachment

Barges

Light vehicles

Fuel trucks


3.3.2 Construction compound and temporary laydown areas

A construction compound and temporary laydown areas will be established on cleared land adjacent to the proposal site. It is anticipated that these sites would accommodate storage of machinery, site amenities, materials and large deliveries. Smaller mobile site sheds are likely to be established.

The laydown areas would be on land that has been cleared and disturbed by previous construction activities and the locations will be identified in the Construction Environmental Management Plan (CEMP) that will be prepared by the Contractor and endorsed by WaterNSW before work commences.

Access to the construction site would be via existing tracks either side of the dam wall.

Fuel will be stored in vehicles on site and taken away each night.

3.3.3 Quarry

About 4,500 m3 of rock would be required to construct the coffer dam and this would be excavated from an existing quarry used for intermittent works undertaken on the structures of the Burrendong Dam. The site is located approximately three kilometres north west of the proposed coffer dam site (refer Figure 3-5).

The material would be excavated from the quarry using excavators, rippers or similar earthmoving equipment, before being stockpiled. Material would then be processed by a rock crushing plant that will also screen and separate the material into different sized fractions. Material would then be loaded onto trucks, covered and transported to the coffer dam site and placed in location.

3.3.4 11kv power line

A section of 11kV powerline would be installed underground between the pad mounted substation and the switchroom at the compressor building. An excavator would be used to construct a trench to install the power cable and this would involve crossing an existing road. All works would be within areas that were disturbed during construction of the dam. Once the cables have been installed, the worksite would be reinstated to pre-existing condition.

FIGURE 3.6

0 160 320 480 640

Meters


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MUMBIL

YARRAGAL

LAKEBURRENDONG

STATEWATER

ROAD

THE C

IRCLE RO

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Legend

Proposed quarry

Proposed site /access / laydown area

Proposed haul route

Undergroundpowerline

Proposal project area


3.3.5 Timing and working hours

As indicated in Section 2.2.2, the proposal is required to be installed prior to February 2020. Construction is expected to commence in November 2019 and take approximately three months to complete. The coffer dam would be constructed over a two to three month period.

Given the criticality of the works, construction may occur 24 hours per day seven days a week to achieve the construction program. The Interim Construction Noise Guidelines (2009) indicates that work may be undertaken outside standard construction hours under certain circumstances, including if it involves public infrastructure works, the extended hours will shorten the length of the project and are supported by the affected community. WaterNSW will consult with affected stakeholders regarding the extended working hours.

Potential impacts and mitigation measures resultant from 24 hour 7 day a week works are assessed in Section 6.11.

3.4 Operation

3.4.1 Overview

The proposal will be operated by WaterNSW. Water flow and allocation priorities will be managed in accordance with the Order to suspend the Water Sharing Plan. As indicated in Section 2.1.2, the Minister for Water issued an order under section 49B of the Water Management Act 2000 to suspend the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 with respect to planned environmental releases, available water determinations and water allocation account management due to an extreme dry period. This suspension reflects that water is to be managed to prioritise water for critical human water needs.

3.4.2 Water Quality Monitoring

A Water Quality Monitoring Plan and a Fish Monitoring Plan will be developed in consultation with DPIE-W, DPIF, NRAR and DPIE. The monitoring program would be implemented to manage impacts associated with the proposal. It would not be a long-term program and would be discontinued once the drought declaration is lifted and the proposal is decommissioned. The Water Quality Monitoring Plan will be implemented by WaterNSW include:

Daily depth profiler monitoring of temperature, DO, pH, EC and turbidity.

Monthly monitoring of nutrient and organic carbon concentrations.

During construction, weekly monitoring of TSS, dissolved metals, and total recoverable hydrocarbons.

Monthly monitoring of algae and cyanobacteria counts and biovolumes.

Visual monitoring of algae on a weekly basis as per the Regional Algal Co-ordinating Committee guidelines and WaterNSW service commission deed.

The Fish Monitoring Plan will include:

Daily visual monitoring for moribund fish that could indicate insufficient aeration by the aeration system.

Daily visual monitoring of the deep water storage for fish deaths, preferably conducted early morning with incidents reported to DPIF based on operational protocols. Dead fish will be removed within two days.


3.4.3 Operation of the proposal

The proposal will be operated by WaterNSW in accordance with an Operating Plan developed by WaterNSW. This will include site specific procedures including monitoring, maintenance and repair and will align with the remainder of WaterNSW water supply network procedures where appropriate.

The aeration system would commence operating before pumping the deep water storage commences to ensure adequate mixing and oxygen transfer to the water. This would involve commencing aeration in November 2019.

The proposal is expected to draw water down until about 6 GL of water remains in the deep storage. The proposal may be operated multiple times to draw the storage level down to the 6 GL level if there are small inflows to Burrendong Dam.

Dubbo Regional Council is upgrading the capacity of its groundwater bore supplies and this work is expected to be completed by May 2020. The proposal aims to enable flows in the Macquarie River to be maintained to supply water to Dubbo until the upgrade of Dubbo’s groundwater system is complete in May 2020.

Figure 3-7 shows the anticipated surface area of the 20 GL deep storage based on a level of 305RL compared to the level anticipated to correspond to the 6 GL draw down level.

3.5 Decommissioning

The proposal would be decommissioned if inflows to the dam are likely to overtop the crest of the coffer dam to enable water to be discharged via the existing outlet infrastructure. The storage level would need to recover to approximately 1% of capacity for this to occur. The proposal will either be fully or partially decommissioned, depending on the magnitude of the inflow.

Partial decommissioning may occur if a small inflow occurs and this may involve removing the pumps, pipes and floating pontoons, however the aeration system is likely to remain in place. Full decommissioning would likely occur if large inflows are predicted and this would involve removing all infrastructure other than the coffer dam, the concrete pads required for the pipeline junctions and the compressor building for the aeration system.

FIGURE 3.7

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Meters


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Anticipated surface area of the 20 GLdeep storage compared to the 6 GL

draw down lever

Legend

Anticipated upstream area benefittingfrom the aeration systen


4. Planning context 4.1 Environmental Planning and Assessment Act 1979

All development in NSW is assessed in accordance with the provisions of the Environmental Planning and Assessment Act 1979 (EP&A Act) and Environmental Planning and Assessment Regulation 2000 (EP&A Regulation). The EP&A Act institutes a system for environmental planning and assessment, including approvals and environmental impact assessment for proposed developments. Implementation of the EP&A Act is the responsibility of the Minister for Planning, statutory authorities and local councils.

As discussed in Section 4.2.1, the proposal does not require development consent under Part 4 of the EP&A Act. The proposal is an activity that requires assessment under Division 5.1 of Part 5 of the EP&A Act.

Section 5.5 of the EP&A Act outlines the duty of determining authorities to consider the environmental impacts of an ‘activity’. When considering an activity, the determining authority is required to ‘examine and take into account to the fullest extent possible all matters affecting or likely to affect the environment’.

Section 5.7 of the EP&A Act requires the determining authority to consider whether an activity is ‘likely to significantly affect the environment’ (including critical habitat) or threatened species, populations or ecological communities, or their habitats. If a determining authority is of the opinion that an activity would be likely to significantly affect the environment, by virtue of a Ministerial order, the activity would then require the approval of the Minister for Planning. Factors that need to be taken into account when considering the likely impact of an activity on the environment are outlined in Clause 228 of the EP&A Regulation. A review of the proposal against Clause 228 is found in Appendix C.

Section 6 of this REF assesses the likely effect of the proposal on the environment. As the proposal is unlikely to result in significant impacts, an environmental impact statement is not required. A REF has been prepared to assess the environmental impacts to satisfy the requirements of Part 5 of the EP&A Act.

WaterNSW as the proponent is also the determining authority for the proposal. In addition to determination under the EP&A Act, WaterNSW is required to notify the Minister for Fisheries under section 199 of the FM Act as the proposal involves activities classified as dredging and reclamation. WaterNSW has notified DPIF and the response was received on 11 November 2019 (refer to Appendix H).

4.1.1 Environmental planning instruments

State Environmental Planning Policy (Infrastructure) 2007

State Environmental Planning Policy (Infrastructure) 2007 (Infrastructure SEPP) includes planning provisions and development control for 25 types of infrastructure works or facilities.


Division 24 of Part 3 relates to Water supply systems. Clause 125 (1) of the Infrastructure SEPP states that development for the purpose of water reticulation system may be carried out by or on behalf of a public authority without consent on any land. A water reticulation system is defined by ISEPP as a facility for the transport of water, including pipes, tunnels, canals, bores, pumping stations, related electricity infrastructure, dosing facilities and water supply reservoirs. The proposal comprises elements such as a pipeline and pumps. These elements are for the purpose of water transport and therefore meet the definition of a water reticulation system and can therefore proceed without the need to obtain development consent under clause 125(1).

Associated construction activities required for the proposal, including extraction of material to construct the coffer dam, does not require consent due to the application of clause 5(3) of ISEPP.

Consultation

Clauses 13, 14, 15 and 16 of the Infrastructure SEPP require public authorities to undertake consultation with councils and other agencies in certain circumstances when proposing to carry out development without consent. The proposal does not require consultation under clauses 13, 14 or 15.

As the proposal involves works on a navigable waterway, WaterNSW will notify Roads and Maritime Authority in accordance with clause 16(2)(e) of ISEPP.

State Environmental Planning Policy (State and Regional Development) 2011

State Environmental Planning Policy (State and Regional Development) 2011 (SRD SEPP) was reviewed to determine whether the proposal requires approval under Part 5.1 of the EP&A Act. The proposal does not meet the criteria for State significant development under Clause 8(1)(a) of the SRD SEPP because it is permissible without development consent under Part 4 of the EP&A Act due to the application of Clause 125 of Infrastructure SEPP.

Under Clause 14(1) of the SRD SEPP, development is declared State significant infrastructure if:

(a) the development on the land concerned is, by the operation of a State environmental planning policy, permissible without development consent under Part 4 of the Act, and

(b) the development is specified in Schedule 3.

Clause 1 of Schedule 3 of the SRD SEPP relates to:

Infrastructure or other development that (but for Part 5.1 of the Act and within the meaning of Part 5 of the Act) would be an activity for which the proponent is also the determining authority and would, in the opinion of the proponent, require an environmental impact statement to be obtained under Part 5 of the Act.

The proposal would not require an EIS under Part 5 of the EP&A Act as it is unlikely to result in significant environmental impacts. As the proposal is not of a type specified in Schedule 3, it is not State significant infrastructure and does not require approval under Part 5.1 of the EP&A Act.

4.1.2 Dubbo Local Environmental Planning The Dubbo Regional Council Local Government Area has two Local Environmental Plans; Dubbo Local Environmental Plan 2011 and the Wellington Local Environmental Plan 2012. Land use for this proposal is subject to the Wellington Local Environmental Plan 2012. The proposal does not require development consent under the Wellington Local Environmental Plan 2012 due to the application of clauses 1.9 and 5.12 of the LEP, and State Environmental Planning Policy (Infrastructure) 2007.


The proposal would be located on land that is zoned E3 Environmental Management under the Wellington Local Environmental Plan 2012.

4.2 Commonwealth legislation

4.2.1 Environment Protection and Biodiversity Conservation (EPBC) Act 1999

The primary objective of the EPBC Act is to ‘provide for the protection of the environment, especially those aspects of the environment that are matters of national environmental significance’ (MNES). Environmental approvals under the EPBC Act may be required for an ‘action’ that has, will have or is likely to have a significant impact on:

MNES matters

The environment on Commonwealth land (whether or not the action is occurring on Commonwealth land)

The environment anywhere in the world, where the action is to be undertaken by a Commonwealth agency.

Approval for such an action may be required from the Australian Government Minister for the Environment.

An ‘action’ is considered to include a project, development, undertaking, activity or series of activities. MNES matters include:

World heritage areas

National heritage places

Wetlands of international importance (i.e. Ramsar wetlands)

Nationally listed threatened species and ecological communities

Listed migratory species

Commonwealth marine areas

The Great Barrier Reef Marine Park

Nuclear actions.

If the proponent considers that an action will have or is likely to have significant impacts on a MNES or on Commonwealth land, a referral is made to the Commonwealth Department of Environment and Energy (DoEE). A proposal may also, but is not required to be referred to the DoEE, where an action will not have or is not likely to have a significant impact. If it is determined through the referral process by the DoEE that an action is likely to have a significant impact on a Matter of NES, or on Commonwealth land, then the project is a ‘controlled action’ and approval from the Minister would be required.

An EPBC Act protected matters search was undertaken on 4 August 2019 which identified several MNES that may occur in, or may relate to, the proposal area. Table 4-1 provides a summary of the results.


Table 4-1 EPBC protected matters search results

MNES matters Results Status

World heritage areas None Not applicable

National heritage places None Not applicable

Wetlands of international significance (RAMSAR sites)

Four:

• Banrock Station wetland complex

• Riverland

• The Coorong, and Lakes Alexandria and Albert Wetland

• The Macquarie Marshes

• 800-900 km downstream of the proposal



• About ~391 km downstream of the proposal

Commonwealth marine areas Not relevant Not applicable

Great Barrier Reef Marine Park

Not relevant Not applicable

Threatened ecological communities

Three:

• Grey Box (Eucalyptus microcarpa) Grassy Woodlands and Derived Native Grasslands of South-eastern Australia

• Natural Temperate Grassland of the South Eastern Highlands

• White Box-Yellow Box-Blakely's Red Gum Grassy Woodland and Derived Native Grassland

• Endangered

• Critically Endangered

• Critically Endangered

Threatened species Twenty nine threatened species:

• Ten birds

• Four fish

• Seven mammals

• Six plants

• Two reptiles

• Critically endangered (4)

Endangered (2)

Vulnerable (4)

• Critically endangered (1)

Endangered (2)

Vulnerable (1)

• Endangered (1)

Vulnerable (6)

• Critically Endangered (3)

Endangered (3)


MNES matters Results Status

• Vulnerable (2)

Listed migratory species eleven • Migratory marine (1)

• Migratory terrestrial (4)

• Migratory wetland (6)

• Birds (18)

Critically endangered (5)

Endangered (1)

Vulnerable (2)

The proposal will not impact upon any world heritage areas, national heritage places, Commonwealth marine areas, or the Great Barrier Reef Marine Park. Potential impacts on threatened species, threatened ecological communities, or migratory species that are listed under the EPBC Act are assessed in Sections 6.4 and 6.5.

4.2.2 Commonwealth Water Act 2007

The Water Act 2007 (Water Act) requires the preparation and adoption of a Basin Plan which provides for the integrated management of Basin water resources. Important functions of the Basin Plan 2012 include providing for:

Giving effect to relevant international agreements to the extent they relate to the use and management of Basin water resources.

Establishment and enforcement of environmentally sustainable limits on qualities of surface water and groundwater that may be taken from Basin water resources.

Basin-wide environmental objectives for water-dependent ecosystem, and water quality and salinity objectives.

Requirements that must be met by water resource plans.

Giving effect to the priority of critical human water needs.

The Basin Plan sets out Water Resource Plan (WRP) requirements, including those relating to critical human water needs and water quality. Clause 86 (A(2)) of the Water Act defines Critical human water needs as the needs for a minimum amount of water, that can only reasonably be provided from Basin water resources, required to meet:

Core human consumption requirements in urban and rural areas.

Those non‑human consumption requirements that a failure to meet would cause prohibitively high social, economic or national security costs.

Each WRP includes a quality management plan that identifies water quality target values and measures to address the water quality of freshwater dependent ecosystems, irrigation water and recreational purposes. WRPs are to describe how extreme dry periods and certain water quality events will be managed. If those dry periods or events would compromise a Basin State’s ability to meet critical human water needs, the WRP must set out measures to ensure critical human water needs are met (Part 13 (2)).

The Water Resource Plan of relevance to the proposal is the Draft Macquarie–Castlereagh Surface Water Resource Plan. The WRP includes an Incident Response Guide (IRG) for managing access to water during an extreme event is a severe water shortage or water quality event. The IRG is discussed in section 2.1.3 and reflects that the proposal will be implemented under a Stage 4 drought to prioritise water for critical human need.


4.2.3 Native Title Act 1993

The objectives of the Native Title Act 1993 are to:

Recognise native title rights and sets down basic principles in relation to native title in Australia.

Provide for the validation of past acts which may be invalid because of the existence of native title.

Provide for a future regime in which native title rights are protected and conditions imposed on acts affecting native title land and waters.

Provide a process by which native title rights can be established and compensation determined, and by which determinations can be made as to whether future grants can be made or acts done over native title land and waters.

Provide for a range of other matters, including the establishment of a National Aboriginal and Torres Strait Islander Land Fund.

The proposal does not involve any construction on Crown land and as such would not impact on any land that is subject to Native title.

4.3 NSW legislation

4.3.1 Water Management Act 2000

The Water Management Act 2000 (WM Act) is the primary piece of legislation established to provide sustainable and integrated management of water in NSW. The Water Management Act 2000 (WM Act) governs the sustainable and integrated management of the State’s water for the benefit of both present and future generations. Under the WM Act, a Water Supply Work Approval (WSWA) is required to use a specified water supply work at a specified location.

WaterNSW has consulted with the Natural Resources Access Regulator and confirmed that the proposal does not require a WSWA or an amendment to the existing WSWA.

The WM Act applies where a Water Sharing Plan (WSP) is issued under the Act has commenced. The proposal is located within the area subject to the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016. Section 56 of the WM Act establishes access licences for the taking of water within a water management area. The proposal does not require a licence to take water.

The WM Act requires controlled activity approvals to carry out specified controlled activities on or under waterfront land. The proposal would be undertaken on waterfront land (within 40 metres of the bed of a river or estuary) and as such comprises a controlled activity under the WM Act. Public authorities such as WaterNSW are exempt from obtaining a controlled activity approval under Clause 41 of the Water Management (General) Regulation 2018. Public authorities such as WaterNSW are also exempt from obtaining a water supply work approval under Clause 38(e)(i) of the Water Management (General) Regulation 2018 if the work is a water tanker that is extracting water for dust suppression.


4.3.2 Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016

The Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 (covers the section of the Macquarie River and the Burrendong Dam where the proposal will be undertaken. The WSP sets the rules for the management of water access licences, water allocation accounts, the extraction of water, the operation of dams and the management of environmental water flows. Section 2.1.3 reflects that under a IRG Stage 4 critical drought/water shortage, the WSP may be partially suspended as part of measures to manage water supplies under the Macquarie-Castlereagh IRG. Given the severity of the drought, on 3 July 2019 part of the WSP was suspended until 30 June 2020, unless the suspension is revoked sooner. The Water Sharing Plan Part Suspension (Macquarie Regulated River) Order 2019 was issued under section 49B of the Water Management Act 2000. It suspends the operation of the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 with respect to planned environmental releases, available water determinations and water allocation account management in relation to the Macquarie Regulated River due to an extreme dry period. The concurrence of the NSW Minister for Energy and Environment was obtained before making this order.

4.3.3 Fisheries Management Act 1994

The Fisheries Management Act 1994 (FM Act) provides for the sustainable management of fish and fish habitats and outlines approval processes for the activities that may impact on threatened fish species and habitats.

The Minister for Fisheries is required to be notified under section 199 of the FM Act of any proposed dredging and reclamation works in ‘waterland’ undertaken by a public authority (other than a Council). The proposal involves work within a waterway to install a coffer dam and this meets the definition of dredging and reclamation. WaterNSW is required to notify DPIF and consider any matters raised by DPIF within 21 days of the notice being given. WaterNSW has notified DPIF and the response is provided in Appendix H which indicates that DPIF does not object to the proposal subject to the specified conditions being complied with.

Under Section 218 (5) A public authority that proposes to construct, alter or modify a dam, weir or reservoir on a waterway (or to approve of any such construction, alteration or modification):

(a) Must notify the Minister of the proposal, and

(b) Must, if the Minister so requests, include as part of the works for the dam, weir or reservoir, or for its alteration or modification, a suitable fishway or fish by-pass.

The proposal will create a coffer dam that forms a small basin around the outlet tower. This would isolate a small portion of the overall extent of Burrendong Dam during times of critical levels of storage in the dam that is below active storage.

Under Section 219 it is an offence to obstruct fish passage. WaterNSW has consulted with DPIF and it was determined by DPI Fisheries that a permit to temporarily block fish passage at the Dam is not required for the proposal.

An aquatic ecology impact assessment was conducted that considers the presence of and potential for threatened species, populations and ecological communities listed under the FM Act to be impacted. Assessments of significance in accordance with section 5A of the EP&A Act were completed for threatened species as detailed in Section 6.4 and D. The assessments concluded that while the proposal will reduce habitat availability for the fish community in Burrendong Dam, it is predicted that there will also be benefits to the water quality and


aquatic ecology which would not be observed under the do-nothing scenario. The proposal is considered unlikely to result in potential significant impacts compared to the do-nothing scenario.

4.3.4 Biodiversity Conservation Act 2016

The Biodiversity Conservation Act 2016 (BC Act) provides legal status for biota of conservation significance in NSW. The BC Act aims to, amongst other things, ‘maintain a healthy, productive and resilient environment for the greatest well-being of the community, now and into the future, consistent with the principles of ecologically sustainable development’. It provides for the listing of threatened species and communities, establishes a framework to avoid, minimise and offset the impacts of proposed development, and establishes a standard method for assessing the likely impacts on biodiversity values and calculating measures to offset those impacts.

This Act applies in relation to animals and plants and not in relation to fish and marine vegetation (refer Fisheries Management Act 1994).

Part 7.2 (1) of the BC Act, states that development or an activity is “likely to significantly affect threatened species” if:

It is likely to significantly affect threatened species or ecological communities, or their habitats, according to the test in section 7.3, or

The development exceeds the biodiversity offsets scheme threshold if the biodiversity offsets scheme applies to the impacts of development on biodiversity values, or

It is carried out in a declared area of outstanding biodiversity value.

Potential impacts on threatened species or ecological communities, or their habitats have been considered in Sections 6.4 and 6.5 and impacts are not considered to be potentially significant.

4.3.5 Biosecurity Act 2015

The Biosecurity Act 2015 guides the management of weeds at the regional level throughout NSW. Under the Act, all plants are regulated with a general biosecurity duty to prevent, eliminate or minimise any biosecurity risk they may pose. Any person who deals with any plant who knows or ought to know of any biosecurity risk, has the duty to ensure the risk is prevented, eliminated or minimised, so far as is reasonably practicable. Individual landholders and managers are required under the Act to control priority weeds for their area according to the relevant biosecurity toolset.

There is the potential for priority weeds to be present on site and this is discussed in Section 6.5. These weeds will be managed in accordance with the Biosecurity Act 2015.

4.3.6 Crown Lands Management Act 2016

No works will take place on Crown land.

4.3.7 Water NSW Act 2014

Under Section 32 of the Water NSW Act 2014, WaterNSW is permitted to enter and occupy land for the construction of new works and to carry out the work on, below or above the surface of the land and to repair, replace, maintain, remove, extend or improve any of its systems for the purposes of carrying out the terms and conditions of its operating licences.

No works are to be undertaken on privately owned land so no consultation or agreements have been completed or obtained.


4.3.8 Heritage Act 1977

The objects of the NSW Heritage Act 1977 include the conservation of heritage and the identification and registration of items of State heritage significance. The Act is concerned with all aspects of conservation, including protection against damage and destruction, to restoration and enhancement. All historic remains and all potential sub-surface archaeological features are subject to provisions of the Act and are therefore afforded concurrent statutory protection.

Section 170 of the Act applies to items listed on a government agency Heritage and Conservation Register are to be impacted. Burrendong Dam is listed on the Section 170 Water NSW heritage and conservation register so a Statement of Heritage Impact (SOHI) was completed (refer Section 6.8).

4.3.9 National Parks and Wildlife Act 1974 (NPW Act)

The National Parks and Wildlife Act 1974 promotes and regulates the management of national parks and historic sites or places of cultural value within the landscape and the conservation of certain fauna, native plants and Aboriginal objects and places.

The NPW Act provides the basis for legal protection and management of Aboriginal sites in NSW. All Aboriginal objects within the state of New South Wales are protected under Part 6 of the NPW Act.

No known Aboriginal sites are located within or in proximity to the work sites (refer to Section 6.7). The proposal will be limited to existing disturbed land and impacts to Aboriginal sites are unlikely. No permits are likely to be required under the NPW Act.

4.3.10 Protection of the Environment Operations Act 1997

The NSW Environment Protection Authority (EPA) is responsible for the administration of the Protection of the Environment Operations Act 1997 (POEO Act). The POEO Act regulates air, noise, land and water pollution.

Activities listed under Schedule 1 of the POEO Act are scheduled activities that require an environment protection licence (EPL). Land-based extractive activities that involve the extraction, processing or storage of more than 30,000 tonnes per year of extractive materials are considered to be a scheduled activity requiring an EPL under the POEO Act. Clause 19 of Schedule 1 defines land-based extractive activity as meaning the extraction, processing or storage of extractive materials, either for sale or re-use, by means of excavation, blasting, tunnelling, quarrying or other such land-based methods. Crushing, grinding or separating activities that process over 30,000 tonnes of material per annum, or have the capacity to process over 150 tonnes per day are scheduled activities under clause 16 of Schedule 1.

The proposal would require about 9,000 tonnes of rock that would be extracted from a quarry. EPA has been consulted and confirmed that the proposal is not a scheduled activity requiring an EPL.

Section 120 of the POEO Act makes it an offence to pollute waters. It is considered that the construction and operation of the project can be carried out without causing water pollution and therefore a licence would not be required. Consultation with the EPA has confirmed that an EPL is unlikely to be required, if spoil is managed in accordance with the methodology set out in this REF.

WaterNSW and its contractors will comply with POEO Act, including the requirement to notify EPA under section 148 if a pollution event occurs that causes or threatens material harm.


5. Consultation 5.1 Community and stakeholder engagement plan

WaterNSW has prepared a Community and Stakeholder Engagement Plan (CSEP) for the Macquarie Valley Drought Temporary Works which outlines:

WaterNSW’s engagement goals and objectives

Key stakeholder groups

Risk management measures

Engagement tools

Policies and protocols for community and stakeholder engagement

WaterNSW aims to provide timely information to manage stakeholder and community expectations and build understanding of the project and its benefits. All communications and engagement activities will be guided by the following principles:

To clearly communicate the objectives of this project.

Consult with stakeholders to inform the development of the detailed business case.

Be proactive. Engage the stakeholders early in the process.

Be open and honest in any communications.

Be inclusive. Ensure stakeholders have access to the process and information about the study.

Be responsive. Respond to stakeholder contact in a timely manner.

Communication and engagement to be flexible and tailored to capture various stakeholders.

Continual monitoring of activities to ensure communication and engagement requirements meet ongoing project stages.

Keep stakeholders up dated and honour commitments made during consultation.

Key stakeholder groups across the broader Macquarie Valley are listed in Table 5-1.

Table 5-1 Key stakeholders

Stakeholder Group Organisation Ministers Minister for Water, Property and Housing, State Ministers Federal Government Commonwealth Environmental Water User State Government Including: Office of Environment and Heritage

National Parks and Wildlife Services State emergency services (SES) Rural Fire Services Department of Industry, Water NSW Local Land Services Department of Primary Industry, Fisheries NRAR


Stakeholder Group Organisation Local Government Including: Warren Shire council

Bogan Shire council Narromine Shire Council Dubbo City Council Mid-western regional council Orana Joint Organisation of Councils, Central NSW Joint Organisation/CENTROC

Major Customer Including Auscott; Agriland; Dubbo City Council; Beitana (Warren); Narromine Irrigation Board of Management; Trangie Nevertire Co-operative; Tenandra Scheme; Nyngan-Cobar Water Supply Scheme; Dubbo Zoo; Fletchers; Mines – Cobar, Tritton, Aurelia Metal; Abattoirs Targeting customers downstream of Warren Weir

Irrigators and other water users

Including: Orana Water Utilities Alliance Cudgegong Water users Macquarie Effluent Creeks Association Lower Bogan Water Users Association Macquarie Marshes Environmental Landholders Association Macquarie River Food and Fibre Lower Macquarie Groundwater Irrigators Association Macquarie Cotton Growers Association Lower Macquarie Water Utilities Alliance Inland Waterways Rejuvenation Association Central West Councils Environment & Waterways Alliance Australian Floodplain Association (AFA) Flood Mitigation Zone Reference Panel NSW Farmers Association NSW Minerals Council Regional Development Australia – Orana Trangie Agricultural Research Centre

Environmental groups

Landcare groups River care groups Inland WaterWays Rejuvenation Association Nature Conservation Council

Community groups Recreational groups Fishing groups - Inland Recreational Fishers

Caravan parks (customers) Indigenous Groups Local Aboriginal Land Councils River front properties All landholders and customers downstream of Warren Weir, Duck

Creek, Crooked Creek, Gunningah Creek, Marebone Creek WaterNSW targeted stakeholder groups

Customer Advisory Groups (CAGs) River Operating Stakeholders Consulting Committee (ROSCCo) WaterNSW Operations Road show – community information sessions


5.2 Consultation relating to this REF

Table 5-2 summarises the activities that have been or are planned to be implemented to consult with the stakeholders in Table 5-1 for the Burrendong Dam Deep Water Storage Access project. Matters raised in these consultation activities will be considered by WaterNSW when implementing the proposal.

Table 5-2 Summary of stakeholder communication and engagement activities undertaken

Date to Happen Stakeholders Communication Activity

Completed 11 February 2019

General community WaterNSW roadshow to discuss current situation, forecasts and plans to extend critical water supply. https://www.youtube.com/watch?v=2vLmvxR8tOg

Completed

9 May 2019 General community (landowners)

Media release on the Macquarie valley; When investigations start; Outcome of investigations and start of construction

Completed

16 May 2019 Community/ targeted groups

Presentation by Operations team to ROSCCo

Updates on project progress, objective and impacts. Representatives to be encouraged to share information with members. https://www.waternsw.com.au/supply/regional-nsw/roscco

Completed

28 May 2019 Targeted groups / community

WaterNSW drought operations roadshow (28/5) - update of works provided to session

Completed

28 June 2019 NRAR OEH

DPI Fisheries

Meeting to discuss approval requirements for upcoming works and impacts including fish passage, aquatic environment, environmental water

Completed

3 July 2019 Targeted groups Customer Advisory Groups (CAGs) – update of works

provided to session

https://www.waternsw.com.au/customer-service/feedback/groups/macquarie-cudgegong-cag

Completed

29-30 July 2019 Affected landowners of power line upgrade

Doorknock landholders affected by the powerline upgrade to discuss upcoming works scheduled for October/November to support the pumping station at Burrendong and accessing the deep storage.

Completed

22 August 2019 Customers and landowners via EWN (email)

Customers (post/email)

Update notification

Completed 26 August 2019

Associations with members downstream of Warren Weir

Contacted association leads to assist with emailing out Operation update


EWN (email) customers and landowners Update on Macquarie Drought Response project Stage

1 works and expected flows from Tuesday 27 August 2019.


EWN (email) customers and landowners Update on Macquarie Drought Response project Stage

1 works and expected flows from Wednesday 28 August 2019.

https://www.youtube.com/watch?v=2vLmvxR8tOg

https://www.waternsw.com.au/supply/regional-nsw/roscco





Date to Happen Stakeholders Communication Activity Completed

1 September 2019 onwards

Affected landowners of power line upgrade

Email and phone contact with landholders to discuss upcoming works and land access agreements and Essential Energy forms

Completed

3 September 2019 Landowners downstream of Warren

Key associations

Operations update encouraging landowners solely reliant on the river and have no alternate water source for domestic supply to log their details. Information will then be provided to NSW Government – Drought Taskforce

Completed

10 September 2019

Affected landowners of power line upgrade Meetings with landholders to arrange meeting to

discuss upcoming works and land access agreements and Essential Energy forms

Completed

16 September 2019

General community Media release on the Macquarie valley; When installation/construction to start; Update on Macquarie Valley projects including bulk water transfer, access to deepwater at Burrendong dam

Completed

17 September 2019

Targeted stakeholders and associations

Provided an update to attendees at the ROSCCo meeting


Completed

19 September 2019

NSW Drought Taskforce Preliminary update to NSW drought taskforce on the

number of landowners registered with no alternate water source

30 October 2019 NSW Drought Taskforce CAG meeting – update on project to be provided

September – October 2019

Affected landholders DPIE (Fisheries) and WaterNSW discuss with landholders the water monitoring project for the Macquarie Drought Response project Stage 1. Further testing in the Macquarie Valley at key sites to continue planning to locate aerators at key refuge pools along the Macquarie River

30 September 2019

Targeted stakeholders Final register to NSW drought taskforce on the number of landowners registered with no alternate water source

17 December 2019

Targeted stakeholders ROSCCO meeting – update on project to be provided

Ongoing Various stakeholders Address various enquiries regarding water supply to local businesses and landholders along the Macquarie River

Ongoing Landowners with no alternate water source Update landowners on options and contact details to

access programs and initiatives provided by NSW Government

Note: Action Plan forms part of the CSEP and will be updated to proactively address and inform stakeholders and community of the proposed works.




5.2.1 Agencies

WaterNSW has consulted with the following agencies during preparation of this REF:

Natural Resources Access Regulator (NRAR)

Department of Planning, Industry and Environment (DPIE)

Department of Primary Industry – Fisheries (DPIF)

Department of Energy and Environment (DoEE)

Table 5-3 provides a summary of the responses received and indicated the sections in this REF where the issues raised have been addressed.

DPIF and DPIE reviewed the draft REF and their comments have been incorporated in the final document.

Table 5-3 Summary of consultation responses

Agency Comment Where addressed

NRAR NRAR was consulted and confirmed that the proposal does not require an approval under the Water Management Act 2000.

Noted

DPIE – Biodiversity Conservation Division (BCD)

Fish entrainment should be considered as part of the REF and any requirement for mitigation measures and/or monitoring should be identified.

Section 3.2.3

Detail should be provided on who would be implementing and funding the water quality monitoring program and what water quality parameters will be tested.

Section 3.4.2

The REF should clarify if there would be upper limit on the size of the residual pool that would remain in the dam after pumping.

Section 3.4.3

The REF should indicate whether monitoring of aquatic refugia, fish and river fauna would be implemented, and if so, which organisation would be implementing and funding the program.

Section 3.4.2

The REF should identify environmental groups that would be consulted.

Section 5.1

The REF should include a commitment to consult with stakeholders that have Basic Landholder Rights or are riparian stock and domestic users downstream of the dam as these groups do not participate in the ROSSCo.

Section 5.2

It was noted that an Aboriginal cultural heritage due diligence assessment has been completed and the three known Aboriginal sites located around the project area would not be impacted.

Section 6.7

The majority of the works would be restricted to the aquatic environment and that works outside of this are mostly confined to areas that have been previously cleared and are devoid of native vegetation.

Section 6.5


Agency Comment Where addressed

DPIF DPIF was consulted and reviewed the draft REF. Comments provided related to potential impacts on biota listed under the Fisheries Management Act 1994, and the need for an appropriate screen to be provided around the pump intakes to minimise the risk of impacts on aquatic biota. WaterNSW has notified DPIF in accordance with section 199 of the Fisheries Management Act 1994 and the response is provided in Appendix H which indicates that DPIF does not object to the proposal subject to the specified conditions being complied with.

Section 3.4.2 (screening) Section 6.3 (Water quality) Section 6.4 (Aquatic biodiversity)

DoEE Potential impacts on MNES need to be considered to determine whether referral is required under the EPBC Act

Sections 6.4 and 6.5

EPA EPA was consulted and confirmed that the proposal is not a scheduled activity and does not require an Environment Protection Licence under the Protection of the Environment Operations Act 1997.

NA

5.2.2 Community

WaterNSW has engaged and consulted with the community during preparation of the REF as indicated in Table 5-2.

Community forums are being planned at various locations in the valley to keep local residents and businesses updated about the upcoming drought relief projects and the implications of critical water levels on water allocation.

A river operations stakeholder consultation committee (ROSCCo) meeting was held in Narromine on 17 September 2019 and this discussed:

Overview of changes to regulations and allocations since previous meeting.

Drought situation update.

Drought outlook including depletion curves, timeline for the Macquarie Drought Response project Stage 1-3.

What are we doing now including update on the temporary raising of the Warren weir and installing temporary structures at Duck and Crooked Creek.

Update on Burrendong Dam deep water storage access project.

What are the priorities for the downstream tributary flows.

Initiatives and support and how to keep informed.

Visit https://www.waternsw.com.au/__data/assets/pdf_file/0011/148574/Macquarie-ROSSCo-Presentation-17-Sept-19.pdf

Previous consultation (prior to project start)

Prior to the Macquarie Valley temporary drought works project, WaterNSW conducted public roadshows to inform the community on the current drought situation compared with previous drought conditions. These sessions were held on 16 January and 11 February 2019, presenting drought water management plans and how measures would be implemented to extend the water supply to meet high security requirements in local towns if the drought situation

https://www.waternsw.com.au/__data/assets/pdf_file/0011/148574/Macquarie-ROSSCo-Presentation-17-Sept-19.pdf

https://www.waternsw.com.au/__data/assets/pdf_file/0011/148574/Macquarie-ROSSCo-Presentation-17-Sept-19.pdf


continued. The presentation included the proposed works. Advertisements were placed in the local newspapers and emails were distributed via WaterNSW’s EWN network. Local council representatives from the Macquarie Valley were invited to attend a targeted briefing on 16 January, 2019 the conditions and plans to manage supply if the drought situation continued and the valley reached Stage 4 (WRP IRG).

WaterNSW also supported Department of Industry (Water) at a presentation on 30 May at Warren. The presentation included plans to manage supply if the drought situation continued which also included the proposed work.

5.3 Future consultation

WaterNSW will continue to engage and consult with affected stakeholders prior to and during implementation of the proposal. This will be undertaken in accordance with the CSEP.

WaterNSW will continue working with DPI (Fisheries) to assess river systems and contribute to discussions around options for managing native fish species levels in the Macquarie Valley. Recent meetings have identified monitoring of priority fish habitat areas along the Macquarie River so that native fish species have the best chance for survival during these critical drought conditions. The proposed works incorporate these priority areas for native fish species along the Macquarie River and are the best option to benefit habitats with the raising of the weir pool. Consultation with DPI (Fisheries) will be ongoing to proactively assess, plan and monitor priority areas and habitats state-wide.

WaterNSW will continue to consult closely with government agencies and inform key stakeholders of the proposed works.


6. Environmental impact assessment 6.1 Land use

6.1.1 Existing environment

Burrendong Dam is a public waterbody that offers year-round recreational access for fishing enthusiasts, water sports, nature lovers, bushwalkers, campers and pick-nickers. The dam’s foreshores are home to two caravan parks, an arboretum and a sport and recreation centre.

The land use surrounding the proposal site is used for rural activities and infrastructure associated with operation of the dam. The proposal site (Lot 27 DP 756882 and Lot 32 DP 859391) and surrounds are zoned E3 Environmental Management under the Wellington Local Environmental Plan 2012 and is owned and managed by WaterNSW. The Lake Burrendong State Park is adjacent to the site and is zoned RE2 Private Recreation.

RMS boating zone classification of the proposal site is a No vessel permitted zone. Under the current drought conditions dam levels restrict the recreational use of the dam and so reduces the numbers of people utilising the dam for recreation.

6.1.2 Potential impact

The proposal would not impact on the existing land use of the site or the surrounding area. The works involve modifying existing infrastructure owned and operated by WaterNSW which will not permanently alter land use. Construction would be limited to areas adjacent to existing infrastructure that have been previously cleared and disturbed during construction and operation of the dam.

Public access to the proposal site would be restricted in the immediate vicinity for safety purposes. As visitors will be able to access areas outside the proposal site there would be a minor short term impact on the amenity due to visual and noise impacts. These impacts and mitigation measures are addressed in Sections 6.12 and 6.11.

The proposal would not alter the boat exclusion zone that is located close to the dam wall and outlet tower as construction would occur within this area. The proposal would draw down the storage which would reduce the surface area of the dam that is available for recreational activities including fishing and boating.

This impact would be temporary and the surface area of the land that is available for recreational use would progressively increase with inflows.

6.1.3 Mitigation measures

Mitigation measure for potential impacts on land use are provided in Table 6-1.

Table 6-1 Land use mitigation measures

Land use mitigation measures

Mitigation required Responsibility Timing

Consultation/notification with dam users WaterNSW Prior to construction/ during operation

Restore disturbed areas and return the site to its original condition

Contractor During construction


Land use mitigation measures

works on a navigable waterway - notify Roads and Maritime Authority.

WaterNSW Prior to construction/ during operation

6.2 Traffic and access

6.2.1 Existing Environment

Sealed roads provide public access to Burrendong Dam and associated infrastructure. Access to the dam and proposal site is along The Cir Road which extends along the dam crest and connects to Burrendong Way. Entry to the proposal site would be via existing gated and locked? unsealed access tracks which extend from the dam crest and lead down to the outlet tower. Material for the coffer dam would be transported from the quarry to the site access track, crossing The Cir Road. Transport would be via a private existing unsealed road established by WaterNSW for monitoring and maintenance works.

All roads used to access the site experience low traffic volumes and are expected to have substantial unused capacity which is typical of a rural environment.

6.2.2 Potential impact

Construction would occur over an estimated three month period and result in temporary impacts to local traffic conditions. Construction equipment is likely to include cranes, excavators, bulldozers, front end loaders, compaction equipment, barges, light vehicles and truck and dogs. During construction, equipment and materials would be delivered by large trucks, most likely semi-trailers and may require temporary road closures to allow for safe vehicle movements. It is likely that the access road to the dam crest, The Cir, would be temporarily closed to the east of the public car park on the eastern side of the dam wall. The construction contractor would implement traffic controls that would involve installing signage to advice motorists of the temporary road closure. Construction vehicle movements are likely to have a small impact on the traffic network as there is expected to be substantial unused capacity to accommodate these vehicles.

Vehicles would park within the construction site, compounds, laydown areas or at the WaterNSW office. Access to the surrounding properties and infrastructure will be maintained during this time.

There will be negligible impact on traffic during operation because vehicle movements would be limited to a small number of light vehicles and trucks that would access the structures for monitoring and maintenance.


Mitigation measures for potential traffic impacts are provided in Table 6-2.

Table 6-2 Traffic and access mitigation measures

Traffic and access mitigation measures

Impact Mitigation Responsibility Timing

Vehicles access All site vehicles would keep to the designated access tracks and parking areas

Contractor Construction and operation


Traffic and access mitigation measures

Temporary road closure A traffic control plan would be prepared in consultation with the relevant road authority.

Contractor Construction

Public safety around construction vehicles

Public access would be restricted as appropriate within the work zone.


Damaged to road or vehicles

Clean and maintain council sealed roads as required


6.3 Hydrology and water quality


Hydrology

The proposal is located within the Macquarie – Bogan Catchment which has a semi-arid climate. Annual rainfall within the catchment ranges from over 1,200 millimetres in the south east to around 300 millimetres in the north-west refer Figure 6-1. Rainfall at Burrendong Dam averages 643 millimetres per year, with a slight summer dominance (WaterNSW 2019).

Evaporation in the catchment has a strong east west gradient, with daily evaporation recorded in Wellington ranging from 1.5 mm in winter and peaking at 8.1 mm in January, refer Figure 6-2.

Figure 6-1 Average annual rainfall in the Macquarie-Bogan catchment


Figure 6-2 Mean daily evaporation for Wellington (BoM website)

Surface water in the Macquarie-Castlereagh Alluvium Water Resource Plan (WRP) is managed through three water sharing plans comprising the regulated Macquarie River, the unregulated Macquarie-Bogan River, and the Unregulated Castlereagh River:

The Macquarie and Cudgegong Regulated River Water Source is defined as the water between the banks of all rivers, from the upstream limit of Windamere Dam storage to the junctions of the Macquarie River and its effluent rivers with the Barwon River.

The Macquarie-Bogan Unregulated Water Sources comprise all of the streams upstream of Burrendong Dam (excluding the regulated Cudgegong River), and all of the tributaries entering the Macquarie and Bogan rivers downstream of Burrendong Dam. There are 30 unregulated water sources managed through this plan.

The Castlereagh Unregulated Water Source comprises all of the streams within the catchment of the Castlereagh River. There are seven management zones managed through this plan.

The catchment is a highly regulated system and forms part of the Murray Darling Basin. The Macquarie River flow is regulated by Burrendong Dam.


The Sustainable Rivers Audit examined the ecological health of the Macquarie River at the end of the millennium drought (2008 – 2010) (MDBA). The audit reached the following conclusions:

Physical form – Moderate condition. Overall the valley’s riverine form was characterised by channel simplification and adjustments in channel size. Elevated sediment loads since European settlement are associated with minor sedimentation within the river channel and moderate to high sedimentation on the floodplain.

Hydrology – The hydrology was in poor condition.

Burrendong Dam

WaterNSW owns and operates the structures of Burrendong Dam. Burrendong Dam regulates the downstream Macquarie River catchment which has been traditionally utilised for town water supplies, industry, and agricultural uses such as irrigation of crops such as cotton; lucerne; oilseed; wheat; cereals and vegetables.

Burrendong Dam impounds Lake Burrendong and is situated on the Macquarie River just below its junction with the Cudgegong River, approximately 30 kilometres south-east of Wellington. Construction began on the dam in 1946 and was completed in 1967, with various upgrades completed on the dam structure since this time. The main wall of the dam is an earth and rockfill structure 76 m high, with a crest length of 1116 m. At capacity, the dam has a surface area of 89 km2 and is 50 m deep at its deepest point. The outlet tower has a 120 mm diameter penstock and trash racks with 50 x 100mm aperture dimensions and 6 mm wire screening. Based on 300 ML/day water releases, water velocity through the trash racks is estimated to be 0.14 m/s increasing to 2.078 m/s at the penstock/pipe. In 2014, a cold water pollution control curtain was installed to mitigate the effects of cold water pollution downstream into the Macquarie River. The dam spillway is a gated concrete chute with a release capacity of 13,720 m3/s.

Macquarie River

Flows in the Macquarie River are heavily influenced by water releases from Burrendong Dam along with large rainfall events in the upper catchment and flows in tributary systems. The river is about 626 kilometres long and is formed when the Campbells and Fish rivers join above Bathurst, followed by tributary flows from the Winburndale River, Turon River and Pyrmul Creek. The Macquarie River then flows into Burrendong Dam, south east of Wellington (refer Figure 1-1).

Below Burrendong Dam, the main tributaries are the Bell River, which enters at Wellington; Little River which enters upstream of Dubbo; and the Talbragar River and Coolbaggie Creek, which enter downstream of Dubbo. West of Dubbo, the Macquarie River provides flows to distributary creeks, wetlands and alluvial river flats associated with braided channels. There is a complex system of anabranches and effluent creeks that connect the Macquarie, Darling and Bogan rivers. The Macquarie Marshes are located toward the downstream end of the catchment and are seasonally wet. The Macquarie River is joined by the Castlereagh River downstream of the Macquarie Marshes and then flows into the Barwon River near Brewarrina.

The two major storages in the catchment are Windamere Dam which has a capacity of 368 GL on the Cudgegong River upstream of Mudgee, and Burrendong Dam on the Macquarie River which has a storage capacity of 1,188 GL, with additional storage capacity of 489 GL in the flood mitigation zone. The volume and pattern of flows in the Macquarie River have been significantly altered by the construction of Burrendong Dam and extraction of water.


As indicated in section 2.1, the current state of water storages in the Macquarie River is significantly impacted by the drought:

Inflows to Burrendong Dam in the last two years are 38% of that received during the previous drought of record.

Burrendong Dam is predicted to be at 0% of active storage by March 2020.

Implementation of the Macquarie Drought Response project Stage 1 works has resulted in flow in the Macquarie River ceasing at Warren. The Macquarie River is not currently connected to the Barwon River.

The full length of the Macquarie River is predicted to cease to flow downstream of Burrendong Dam by March 2020 if there are no inflows. This would affect a section of the river about ~314 kilometres long between Burrendong Dam and Warren.

The primary environmental asset in the catchment is the Macquarie Marshes on the lower reaches of the Macquarie River, parts of which are listed as a Wetland of International Importance under the Ramsar Convention. The Marshes are a large and diverse wetland system that provide habitat for a diverse range of species of plants and animals and have supported some of Australia’s largest waterbird breeding events.

Water quality in Burrendong Dam

The in situ water quality at Burrendong Dam was sampled on 28 August 2019 and the results are presented in Table 6-3. These results indicate that dissolved oxygen concentrations in the dam are currently high, and are supersaturated in the Macquarie River downstream of the outlet, which is likely associated with the physical aeration of the released water.

EC in the dam exceeded the default guideline value (DGV) for freshwater reservoirs, though in the Macquarie River the similar EC value was below the DGV for lowland rivers. The observed oxidation-reduction potential (ORP) values indicated oxidative conditions at both the dam and the Macquarie river immediately downstream.

Table 6-3 In situ water quality results, 28 August 2019

Parameter Units Burrendong Dam

Macquarie River

DGV

Freshwater reservoirs

Lowland rivers

Temperature °C 11.9 11.6 NA NA DO % Sat. 94.6 114.2 90-110 85-110

mg/L 10.17 12.23 NA NA EC µS/cm 457.5 459.5 20-30 125-2200 pH pH units 8.39 8.42 6.5-8.0 6.5-8.5 ORP mV 161.2 162.1 NA NA

Laboratory analysis

The results of laboratory analyses of the samples collected on 28 August 2019 are presented in Table 6-4. These results indicate that TSS concentrations and turbidity values were low at both sites. The dominant major ions in the dam were calcium and bicarbonate.

Low concentrations of dissolved heavy metals were observed, with the nickel being the only metal observed at or above its laboratory limit of reporting (LOR). No exceedances of the DGVs for metal toxicants were observed.


Elevated nutrient concentrations were observed at both sites. This included exceedances of the DGVs for NOx and TN at both sites, and for TP in the dam. The DGVs for these parameters are associated with the risk of nuisance algal blooms. TKN concentrations indicated that the majority of the nitrogen at both sites is present as organic nitrogen, followed by NOx and ammonia. RP (orthophosphate) concentrations at both sites were below the laboratory LOR, which indicates that algal growth in the dam is likely phosphorous limited, as orthophosphate is the only form of phosphorous that autotrophs can assimilate (Correll 1999).

DOC concentrations at both sites were relatively high, which indicates the potential risk of low DO concentrations, as decomposition of DOC consumes DO.

Chlorophyll a concentrations, which are regularly used as a proxy for phytoplankton biomass (Huot et al. 2007), were below the DGV at both sites.

Table 6-4 Results of laboratory analysis of samples collected 28 August 2019

Parameter Units LOR Burrendong Dam

Macquarie River

DGV


Lowland rivers

Physicochemical parameters TSS mg/L 5 <5 5 NA NA Turbidity NTU 0.1 2 1.8 20 50 Major ions Chloride mg/L 1 42 40 NA NA Sulfate as SO4 mg/L 1 38 39 NA NA Total alkalinity as CaCO3

mg/L 1 118 118

NA NA

Calcium mg/L 1 36 34 NA NA Magnesium mg/L 1 18 17 NA NA Sodium mg/L 1 33 32 NA NA Potassium mg/L 1 5 5 NA NA Dissolved metals Aluminium mg/L 0.01 <0.01 <0.01 0.055 0.055 Arsenic mg/L 0.001 <0.001 <0.001 0.013 0.013 Cadmium mg/L 0.0001 <0.0001 <0.0001 0.0002 0.0002 Chromium mg/L 0.001 <0.001 <0.001 0.001 0.001 Copper mg/L 0.001 <0.001 <0.001 0.0014 0.0014 Lead mg/L 0.001 <0.001 <0.001 0.0034 0.0034 Nickel mg/L 0.001 <0.001 0.001 0.011 0.011 Selenium mg/L 0.01 <0.01 <0.01 0.011 0.011 Zinc mg/L 0.005 <0.005 <0.005 0.008 0.008 Iron mg/L 0.01 <0.05 <0.05 NA NA Mercury mg/L 0.0001 <0.0001 <0.0001 0.0006 0.0006 Nutrients Ammonia as N mg/L 0.01 0.1 0.12 0.900 0.900 NOx as N mg/L 0.01 0.16 0.2 0.010 0.040 TKN as N mg/L 0.1 0.7 0.4 NA NA TN as N mg/L 0.1 0.9 0.6 0.350 0.040 TP as P mg/L 0.01 0.04 <0.01 0.010 0.050 RP as P mg/L 0.01 <0.01 <0.01 0.005 0.020



Macquarie River

DGV


Lowland rivers

Other DOC mg/L 1 10 10 NA NA Chlorophyll a mg/L 0.001 0.004 0.002 0.005 0.005

In situ profiler data 13 September 2019

The temperature profile in Burrendong Dam on 13 September 2019 is presented as Figure 3.1 in Appendix D. This figure shows that water in the dam was stratified by temperature, with water at 16 metres below the surface being slightly over 2 degrees Celsius colder than that at the surface.

Figure 3.2 in Appendix D shows that DO saturation was highest at the surface of the dam, and decreased gradually with depth, though anoxic conditions were not observed even at the lowest depth (16 metres).

pH was about 8.4 at the surface of the dam, and reduced to 8.0 at a depth of 16 metres (Figure 3.3 in Appendix D) this spatial trend is likely associated with algal photosynthesis being greatest at the surface, which removes dissolved carbon dioxide and results in bicarbonate being more dominant, thus affecting pH.

Figure 3.4 in Appendix D shows that turbidity increases with depth in the dam, though none of the turbidity values observed pose any risk for aquatic life.

Depth profile chemistry and algae data

Figure 3.5 in Appendix D shows the concentrations of major cations (calcium, magnesium, sodium and potassium) at depths in Burrendong Dam between the surface and 30 metres. The sampling was undertaken on three occasions, in October, November and December 2017. These data indicate that there was no salinity stratification observed in the dam. This is also shown by Figure 3.6 in Appendix D , which shows that there were no spatial trends in the concentrations of the major anions chloride, sulfate and bicarbonate.

TN concentrations were shown to generally increase with depth in the Burrendong Dam reservoir (Figure 3.7 in Appendix D). This may be due to the effect of biomass incorporation of nitrogen in the water column, which would be likely to be greater near the surface of the reservoir due to higher algae densities in this part of the water column compared to lower depths. No similar trend in TP concentrations was observed (Figure 3.8 in Appendix D), which likely indicates that the majority of the phosphorous present was not available for assimilation by autotrophs.

Figure 3.9 in Appendix D shows that total algae and total cyanobacteria counts were highest in December 2017, and for each profile were highest towards the surface of the dam. These observations are to be expected based on light availability. Figure 3.10 and 3.11 in Appendix D show that the algal and cyanobacterial biovolumes were highest in December 2017, at three metres below the surface of the dam.

Groundwater

The Groundwater Dependent Ecosystem (GDE) Atlas indicates that the Macquarie River downstream of Burrendong Dam is mapped as the following:

Terrestrial GDEs are likely to be inflow dependent ecosystems that are reliant on water in addition to rainfall


Aquatic GDEs between Burrendong Dam and Wellington are mapped as moderate potential and low potential. Burrendong Dam itself was not classified as an aquatic GDE.

6.3.2 Potential impacts

Construction

Potential impacts to surface water quality during construction would be limited to activities associated with the installation of new infrastructure and construction of the coffer dam at Burrendong Dam.

The coffer dam would be created by constructing an earth embankment to create a small basin around the outlet tower. The construction would be undertaken in three stages:

1. Install a silt curtain in the water to minimise the risk of residual debris and silt reaching surrounding areas of the waterway.

2. Construct the first half of the coffer dam with a culvert with penstock.

3. Construct second half of the coffer dam with the use of the culvert and penstock to allow flows during the second half of the coffer dam to be completed.

An excavator would undertake works within Burrendong Dam above the waterline of the reservoir to deposit rock to form the coffer dam. The excavator would use material from a quarry located approximately three kilometres north west of the proposed coffer dam.

The installation of a pump station and associated pipelines involves six partially submerged pumps on two prefabricated pontoons

Works within the waterway pose the following risks to water quality during construction:

Fuel spills entering the reservoir

Sediment (soil, gravel, concrete washings) entering the reservoir and increasing turbidity

These impacts would be short term and limited to the construction period. Management measures would be implemented to minimise potential impacts.

There is potential for erosion and subsequent sedimentation and an increase in turbidity within the vicinity of works to construct the coffer dam. The risk of increased turbidity in the dam to the extent that there would be adverse impacts on aquatic fauna is considered low.

There is a risk that spills of fuel, hydraulic fluids and lubricating oils used in construction equipment could release hydrocarbons and metals into the environment. Spill containment measures (such as drip trays) would be used and no refuelling would occur within 40 metres of the waterway. It is unlikely that the water quality would be significantly impacted provided the mitigation measures detailed in section 5.2 are implemented.

Given the small area of soil that would be disturbed, any increased risk of water quality being impacted by turbid runoff from exposed areas is minor. Monitoring of weather and rainfall events would occur as well as river levels upstream to ensure that the work site is closed prior to any tributary flows occurring that have the potential to inundate work areas.

The Macquarie River Catchment can experience large flood events, however there is significant notice of any tributary flows that have the potential to result in flooding. The proposal would take place during a severe drought and Burrendong Dam is currently at 4 % capacity (1 October 2019). If there is a significant rain event, there is ample capacity within Burrendong Dam to capture flows to mitigate the effects of flooding. If significant rainfall occurs that leads to large tributary flows upstream of Burrendong Dam, WaterNSW would suspend construction


and move equipment to a location that is unlikely to be affected by rising water levels. If there is substantial inflow to the storage that has the potential to inundate the work site, it is likely that the temporary drought response measures would be deferred.

Flows to the downstream Macquarie River would not be adversely impacted by construction of the proposal.

As construction would involve activities that are classified as dredging and reclamation, WaterNSW is required to notify the DPIF under section 199 of the Fisheries Management Act 1994. Matters raised by the DPIF within 21 days of the notification being given are required to be taken into consideration. DPIF have been consulted as part of the preparation of this REF and provided feedback and advice in regards to pump intake structure design requirements. WaterNSW has notified DPIF and the response is provided in Appendix H which indicates that DPIF does not object to the proposal subject to the specified conditions being complied with.

Operation

Hydrology and water quality

The proposal would extend the duration of flows in the Macquarie River downstream of Burrendong Dam, and due to the volumes provided and the aeration received at the dam outlet, the water quality of these flows would be supportive of aquatic life in the downstream habitats.

In the 6 GL of inactive deep storage proposed to be retained in within the Burrendong Dam reservoir, evapo-concentration is unlikely to result in significant impacts based on the existing water quality, where even a 10 fold increase in parameter concentrations (i.e. evaporation of 90 percent of the 6 GL) listed in Table 6-4 is unlikely to result in any potentially ecotoxic concentrations of metals.

Elevated nutrient concentrations in Burrendong Dam reservoir may occur as a result of the following:

Evapo-concentration

Decomposition of organic matter present in the deep water storage

Inflows of water with elevated nutrient concentrations or elevated organic matter concentrations, which could lead to elevated concentrations through decomposition

The potential impacts of elevated nutrient concentrations include nuisance algal blooms and the associated risk of low DO saturations, and potential toxicity to aquatic life due to ammonia toxicity. These impacts are unlikely because the aeration system is expected to minimise the risk of the development of hypoxic conditions in the deep water storage, and the high DO saturations provided by the system would likely minimise the risk of a build-up of ammoniacal nitrogen, which would be removed from the system through nitrification and biomass incorporation.

The aeration system is also likely to prevent low DO concentrations following a potential dam turnover event. In the case of such an event, the lower layer of water would be oxygenated, in contrast to a turnover event under the do-nothing scenario, which would result in the lower anoxic water being brought to the surface of the dam. If there are anoxic inflows to the reservoir, the aerator is likely to have a positive impact in the vicinity of the aeration system by reducing the severity and duration of anoxic conditions by mixing water.


Groundwater

The proposal would prolong the duration that water is maintained in the section of the Macquarie River between Burrendong Dam and Warren. Infiltration along this section of the waterway has the potential to benefit aquatic and terrestrial GDEs present adjacent to the river.


Table 6-5 Hydrology and water quality mitigation measures

Hydrology and Water Quality Mitigation Measures


Elevated turbidity as a result of construction

Install and maintain sediment control devices between the coffer dam and deep water storage in line with the CEMP

Wash down areas are to be located away from water areas and are to have appropriate sediment control measures implemented

Construction contractor, WaterNSW

Construction

Spills Control, contain and clean up spill using methods detailed in the CEMP

No vehicles to be refuelled on site

Spill containment measures to be used at all times

Spill kit to be kept on site at all times

Machinery is to be inspected daily for oil, fuel and other liquids leaking.

No fuels, chemicals or lubricants are to be stored overnight unless prior approval from WaterNSW is granted

Construction contractor

Construction, operation

Flooding Develop flood response measures to be implemented in the event of heavy rainfall leading to potential flooding

WaterNSW Construction

Low dissolved oxygen levels in deep water storage

Monitor dissolved oxygen levels within deep water to assess effectiveness of aeration

WaterNSW Operation

Blackwater event in Burrendong Dam following heavy rainfall

Assess dissolved oxygen levels and modify the aeration system accordingly.

WaterNSW Operation


6.4 Aquatic biodiversity

6.4.1 Water Quality and Aquatic Ecology Impact Assessment

A Water Quality and Aquatic Ecology Impact Assessment has been prepared for the proposal and is provided as Appendix D.


Aquatic habitat observed at Burrendong Dam and Macquarie River during a site inspection on 28 August 2019 was classed as good and excellent respectively (Appendix D). The reaches of the Macquarie River downstream of Burrendong Dam are known to support populations of native fish species, including species protected under the EPBC Act and/or the FM Act, such as Murray Cod, Eel Tailed Catfish, Silver Perch and Trout Cod.

Key observations from the habitat assessment on 28 August 2019 are presented in Table 6-8, along with site photos.

Table 6-6 Burrendong Dam Photos and habitat observations, 28 August 2019

Burrendong Dam

1) Looking south east

2) Looking east

As seen in photos 1 and 3, the substrate in Burrendong Dam is comprised of a mix of silt, sand, gravel and pebbles, with some cobbles present. Much of the substrate is covered with filamentous algae, with no macrophytes present.

Some early growth of Azolla sp.was present (photo 2), however this appeared to be limited to the area around the offtake infrastructure.

Elevated algae concentrations were indicated by the green colour of the water as seen in Photo 1.

There was little submerged woody habitat (SWH) available, as it was limited to the occasional branch, as seen in Photo 3 for example.

Due to the low water level in the dam, there was very little riparian vegetation near the edge of the surface water and as a result, minimal shading.


3) Looking west

Sustainable Rivers Audit

The Sustainable Rivers Audit (SRA1) is a systematic assessment of the health of river ecosystems in the Murray–Darling Basin using data gathered in 2004- 2007. Sustainable Rivers Audit 2: The ecological health of rivers in the Murray–Darling Basin relates to ecosystem health at the end of the Millennium Drought (2008–2010).

The audit found that Macquarie River system’s fish, benthic macroinvertebrate and riverine vegetation communities were in Extremely Poor, Moderate and Moderate condition respectively, while physical form and hydrology were both in Moderate condition. The condition ratings for the fish, macroinvertebrate and riverine vegetation themes were used to derive an Ecosystem Health Index. The River Ecosystem Health was rated as Very Poor (Lowland zone: Poor; Slopes zone: Very Poor; Upland zone: Very Poor). The proposal is within the Slopes zone as defined by this audit.

The Macquarie Valley river ecosystem was in Very Poor health. Within the Slopes zone the River Ecosystem Health was rated as very poor. The fish community was in Extremely Poor condition. Many expected species were absent. Species count, abundance and biomass were dominated by exotic species; recruitment levels among the remaining native species were very low. The macroinvertebrate community was in poor condition, with moderate to substantial declines in the frequency and occurrence of expected macroinvertebrate families. Riverine Vegetation was in moderate condition overall, with reduced abundance, structure and nativeness in the Near Riparian and Lowland Floodplain domains, The Physical Form of the river system was in Moderate condition with bank dynamics in Good condition and channel form and bed dynamics in Moderate condition. There were moderate to high levels of floodplain sediment deposition. The Slopes zone’s Hydrology was in Poor condition, with mainstem river reaches experiencing considerable change from Reference Condition in low and zero flow events; minor alteration in low and high over bank floods, flow variability and flow seasonality; and little or no alteration in high flow events and flow gross volume.

Environmental conditions

The existing drought conditions and Macquarie Drought Response project Stage 1 measures have resulted in the Macquarie River ceasing to flow at Warren in September 2019. The Macquarie River ceased to flow downstream of the Macquarie Marshes in December 2018 and in July 2019 the cease to flow point was in the southern marshes below the Oxley hydrometric station.


Section 2.1.3 reflects that the part of the Water Sharing Plan that relates to environmental watering was suspended on 3 July 2019 and this means that environmental water will not be delivered downstream of Burrendong Dam.

The environment downstream of Burrendong Dam is currently responding to the ongoing drought conditions and impacts associated with reduced availability of water. The drought has resulted in water levels and tributary flows declining and contracting to the deeper pools. In the absence of inflows, over time these pools would contract further which has the potential to result in declining water quality and lead to events such as fish kills. There would also be reduced water available to the terrestrial ecological elements, including mobile species.

In the absence of significant inflows and drought relief works, the Macquarie River is predicted to cease to flow downstream of Burrendong Dam in March 2020, assuming that Stage 2 of the drought response measures occurs in December 2019 which involves a release from Windamere Dam to Burrendong Dam. This would affect the ~314 kilometre long section of the river between Burrendong Dam and Warren. If this occurs, it is likely to result in similar ecological responses along this section of the Macquarie River to that which is currently occurring between Warren and the Barwon River, and has been occurring in the Darling River at places such as Menindee. This would result in water quality and aquatic ecology impacts in deep pools both downstream of Burrendong Dam that DPIF considers to be ecologically important.

Darling River EEC

The aquatic ecological community in the natural drainage system of the lowland catchment of the Darling River (Darling River EEC) is listed under the FM Act and includes all native fish and aquatic invertebrates within all natural creeks, rivers, streams and associated lagoons, billabongs, lakes, flow diversions to anabranches, the anabranches, and the floodplains of the Darling River within the State of New South Wales, and including Menindee Lakes and the Barwon River. The sections of the Macquarie River downstream of Burrendong Dam are part of this EEC. The Final Recommendation of the Fisheries Scientific Committee indicates that ‘in its natural state, many of the water-bodies in this EEC are characterised by variable and unpredictable patterns of high and low flows.

The TECs and threatened species listed under the BC Act, FM Act and EPBC Act as being recorded in the locality or have the potential to be present in the locality may occur within the Darling River EEC. Appendix D outlines the likelihood of occurrence of these threatened entities and reflects that there is the possibility of threatened entities being present in terrestrial and aquatic environments within and downstream of Burrendong Dam.

Macquarie Marshes

The Macquarie Marshes is a Ramsar listed wetland, totalling 19,850 hectares in central northern NSW, approximately 100 kilometres north of Warren. The Macquarie Marshes contain a wide range of vegetation types, determined by the frequency and duration of flooding, including River Red Gum woodland, Water Couch grasslands, extensive beds of Common Reed, Coolibah, Black Box, Lignum, reed swamp, Cumbungi and River Cooba. The marshes support a diverse array of wildlife, including migratory birds and threatened species (Department of Environment and Energy, 2019c). The marshes also support highly significant habitat for waterbirds that breed in colonies, providing breeding habitat for 16 colonial nesting waterbird species.

The Macquarie Marshes receive environmental water allocation under the Water Sharing Plan for the Macquarie-Cudgegong Regulated Water Source 2003 via the Macquarie River, Bulgeragar Creek, Marthaguy Creek and Gum Cowel. The available water determination and allocation of shares to general security access licences determines the amount of water


available from regulated flows for the irrigation industry and the environment. As noted in Section 2.1.3, on 3 July 2019, the part of the Water Sharing Plan that relates to environmental releases has been suspended. This order will be in place until 30 June 2020 unless revoked sooner and was made with the concurrence of the DoEE.

Aquatic biota

The Macquarie River and Burrendong reservoir is mapped as Key Fish Habitat (DPI, 2019) by the NSW Department of Primary Industries. Threatened species distribution mapping produced by DPI (2019) identify indicative habitat for Trout Cod, Olive Perchlet, Purple Spotted Gudgeon, Silver Perch and Eel tailed Catfish within the vicinity of the proposal.

NSW DPI Fisheries sampled fish communities as part of a Short-term intervention monitoring of a fish community response to an environmental flow in the mid and lower Macquarie River: 2014/15 water year (DPI, 2015). This involved sampling in four spatially, geomorphologically and hydrologically different zones at a landscape scale:

Zone 1: Macquarie River Burrendong Dam to Dubbo – about a 100 kilometre long stretch of river below Burrendong Dam to Dubbo.

Zone 2: Macquarie River Gin Gin to Warren – about a 100 kilometre long stretch of river upstream of the Macquarie Marshes, between Gin Gin and Warren. The majority of Zone 2 is upstream of the Warren Weir and is included sampling between the Warren Weir and Gin Gin Weir.

Zone 3: Macquarie Marshes. The majority of this zone is downstream of the Marebone regulator.

Zone 4: Lower Macquarie River (below the Macquarie Marshes). This is about a 100 kilometre long stretch of the river between Bells Bridge and the Barwon River confluence. Sampling was not undertaken at some site in Zone 4 during two of the three sampling events because the river was dry.

In general, this study concluded that native fish species richness was significantly lower within, and downstream of, the Macquarie Marshes compared with sites sampled upstream. The overall condition of the fish community within the Macquarie River declined along a downstream gradient from ‘poor’ below Burrendong Dam to ‘extremely poor’ in the Macquarie Marshes and downstream to the Barwon River confluence.

Threatened fish species recorded by DPIF include:

Murray Cod – this is listed as vulnerable under the EPBC Act. This species was recorded in Zones 1 (12 records), 2 (214 records) and 3 (19 records). This reflects that the highest abundances were recorded from Gin Gin to Warren.

Silver Perch – this is listed as vulnerable under the FM Act and critically endangered under the EPBC Act. This species was recorded once and that was in Zone 2.

Trout Cod – this is listed as endangered under the FM Act and EPBC Act. This species was recorded once and that was in Zone 1.

Eel Tailed Catfish – This species is an endangered population under the FM Act and was recorded in Zones 1 (24 records) and 2 (3 records).


Construction impacts

The proposal would have a localised disturbance footprint over the three month construction timeframe. Impacts to aquatic habitat in Burrendong Dam are likely to be negligible during


construction and would be limited to the two to three week construction period for the coffer dam.

Potential indirect effects on aquatic habitat during construction include the following:

Erosion and sedimentation: uncontrolled erosion of soil from the proposal site and the corresponding deposition of this material in the deep storage area. This process could reduce aquatic habitat values in the deep storage area.

Pollutants: Water quality impacts could occur during construction if fuel or chemical spills from construction vehicles or equipment enter the deep storage area.

Construction impacts would be minimised by implementing the mitigation measures in section 6.4.3 and are unlikely to be significant.

Operational impacts

The Macquarie River would cease to flow in March 2020 if the proposal is not implemented and this would affect the ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren, resulting the potential impacts outlined in section 2.2.1.

From an ecological perspective, the proposal would enable a cease to flow event in the main channel of the Macquarie River between Burrendong Dam and Warren to be delayed by about three months, therefore delaying the time at which the main channel of the river is likely to begin to revert to a series of pools.

The proposal would have substantial beneficial ecological impacts by maintaining flows within the ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren which is mapped as key fish habitat by NSW DPI Fisheries and provides habitat for threatened fish species such as Murray Cod, Silver Perch and Eel-tailed Catfish. The section of the Macquarie River near Dubbo also has a population of Trout Cod, which is listed as endangered under the EPBC Act and FM Act. Maintaining flows in the river would also reduce the risk of pools stagnating and the development of poor water quality that has the potential to impact on aquatic ecology.

The proposal would reduce the habitat availability for the fish community in Burrendong Dam. However, compared to the do-nothing scenario, the habitat quality in the deep water storage would be improved because:

The aeration system is likely to maintain DO levels above 1.58mg/L in the vicinity of the aeration system which, for the native species likely to be present within the reservoir, is the highest lethal threshold . A DO level of 1.58 mg/L is the lethal threshold for Murray Cod and the lethal threshold for other native species likely to be present is below this concentration. No data is available for Trout Cod, however it is assumed that DO sensitivity would be similar to Murray Cod as they are known to hybridise.

Exotic Common Carp may be removed from Burrendong Dam by commercial fishing to reduce biomass and competition with native species. If commercial fishing occurs, this would take place when reservoir levels are reducing due to the pumping to maximise the catch rate.

Any dead fish would be removed from the deep water storage within two days as per the Fish Monitoring Plan, minimising the potential impact on organic carbon and nutrient concentrations.

Fish may become trapped in the coffer dam during the operation of the proposal. As there is existing screening around the outlet tower there is likely to be negligible additional impact as it is not anticipated that the proposal would increase the discharge velocities because operation would occur in the low range of the bell-mouth/ outlet tower.


The proposal has the potential to adversely impact water quality, primarily in the deep water storage. The most likely impacts are elevated EC and concentrations of nutrients and organic carbon. Any increase in EC through evapo-concentration is unlikely to have lethal effects on the fish population, though elevated EC may act as a stressor for some fish including Murray Cod.

Elevated nutrient concentrations have the following potential adverse effects on aquatic life:

Elevated concentrations of ammonia can result in acute and chronic toxicity.

Elevated nutrient concentration can promote nuisance algal blooms, which can result in anoxia and fish kills.

Algal scum or dense Azolla sp. coverage can prevent light penetration and thereby limit oxygenation of deeper water through photosynthesis.

Appendix D identifies which fish species that are likely to be impacted by the proposal. Assessments of Significance have been prepared for the Darling River EEC and following species (Appendix D)

Maccullochella macquariensis (Trout Cod) – Endangered species (EPBC Act and FM Act)

Maccullochella peelii (Murray Cod) – Vulnerable species (EPBC Act)

Bidyanus bidyanus (Silver Perch) – critically endangered species (EPBC Act), Vulnerable species (FM Act)

Tandanus tandanus (Eel -tailed Catfish) – Endangered Population (FM Act).

This proposal is considered unlikely to significantly impact on the Darling River EEC or these species for the following reasons:

The proposal is a temporary measure and would be decommissioned once storage levels rise and water can be discharged by the existing outlet infrastructure.

The proposal would have a positive impact by delaying a cease to flow event in the ~314 kilometre long section of the river that is considered to provide higher quality habitat for threatened biota relative to the habitat that is contained within Burrendong Dam. The proposal would change the timing of the cease to flow event downstream of the dam, but would not change whether this event occurs unless there are inflows.

All reasonable and feasible management measures would be implemented to minimise potential impacts. This will include a Water Quality Monitoring Plan and Fish Monitoring Plan developed to manage distressed fish in consultation with DPI Fisheries. The measures contained within these plans are likely to be similar to those that are being implemented to respond to a cease to flow event in the Macquarie River downstream of Warren. The overall management of the fishery remains a core function of DPI Fisheries as they are the NSW State agency managing fish and administering the Fisheries Management Act. WaterNSW has ongoing consultation with DPI Fisheries. The proposal would not impact on the delivery of environmental water to downstream environments including the Macquarie Marshes, unless supplementary flows are declared, because the environmental water is not available to be used in the 2019/2020 water year. An order has been gazetted under section 49B of the Water Management Act 2000 that suspends the part of the Water Sharing Plan that relates to environmental releases.


Table 6-7 details the mitigation measures that will be undertaken in response to the potential impacts of the proposal.


Table 6-7 Mitigation measures for potential impacts on aquatic ecology

Potential impact Mitigation measures Algal blooms observed in the deep water storage or the Macquarie River

Monitor DO regularly in the area of the algal bloom to assess the need for localised aeration to minimise the risk of fish kills. If monitoring indicates that aeration is not sufficient to control algal growth, WaterNSW would investigate the feasibility of alternative methods such as chemical controls. WaterNSW would consult with DPI Fisheries if additional controls are proposed to be implemented.

Fish kills in the deep water storage or Macquarie River

Remove dead fish within two days. Investigate water quality data to determine cause of fish deaths and modify the aeration system if appropriate.

A visual inspection of the waterway for dead or distressed fish (indicated by fish gasping at the water surface, fish crowding in pools or at the water edge) is to be undertaken during the works. Observations of dead or distressed fish are to be reported immediately to the District Fisheries Officer at Bathurst (02 6331 1428).

Moribund fish observed in the deep water storage

Investigate efficacy of the aeration system and modify if appropriate. Undertake an additional inspection of the deep water storage on the same day to remove any dead fish.

The fish biomass in the deep water storage exceeds sustainable levels

Remove as much exotic species biomass as practicable.


6.5 Terrestrial biodiversity

This section assesses the terrestrial biodiversity values likely to occur within the proposal site and potential impacts to these values. Due to the nature of the proposed works which are primarily restricted to the aquatic environment, the terrestrial assessment focuses on impacts associated with proposed access roads, compound and laydown areas and quarry.

6.5.1 Methodology

The terrestrial biodiversity assessment included a desktop review of available documents and government databases including: NSW Biodiversity Conservation Division (BCD) BioNet Atlas for records of threatened biota previously recorded in the locality (website for the Atlas of NSW Wildlife) (BCD 2019a).

NSW BCD Threatened biodiversity profile search (BCD 2019b).

Department of the Environment and Energy (DoEE) Protected Matters Search Tool for biota listed under the EPBC Act that are known or predicted to occur in the locality (DoEE 2019a).

DoEE online species profiles and threats database (DoEE 2019b).

BCD Vegetation Information System (VIS) for Plant Community Types surrounding the proposal site (BCD 2019c).

Regional vegetation mapping - Central West Lachlan VIS_ID 4682 (DPIE, 2015)

Other ecological resources reviewed included:

NSW Sharing and Enabling Environmental Data (SEED) Portal (NSW Government 2019).

Priority weeds for the Central West (DPI, 2019a).

Aerial photographs and satellite imagery of the study area.

Searches were generally undertaken for the potential storage area with a 10 km buffer, referred to as the ‘locality’.


Proposal site

The majority of works associated with the proposal would be restricted to the aquatic environment. Impacts to terrestrial habitat are discussed below.

Dam structure

The proposal site is located within Burrendong Dam’s inundation area and in the immediate vicinity of the dam wall. The majority of the proposed works would occur within its inundation area. The dam structure is unlikely to provide any substantial habitat for threatened flora and fauna. Species which may utilise the dam structure itself may be migratory birds such as the White-bellied Sea-eagle (Haliaeetus leucogaster) and the Australian Painted-snipe (Rostratula australis). Whilst these species may utilise the dam structure itself, their occurrence within the proposal area is likely to be a fly-over to more suitable foraging or roosting habitat to the west of the proposal site. A full list of flora and fauna species likely to occur within the proposal site is located in Appendix F.


Quarry

The proposal site includes an existing quarry (Figure 3-5) that is used by WaterNSW for any maintenance of the existing dam structures. The proposed site has been cleared and vegetation is limited to ground cover that has colonised the site following clearing. For these reasons, the proposed quarry site is unlikely to provide habitat for any threatened biota.

Access tracks

There are existing dam access tracks either side of the dam wall that are likely to be suitable for the plant and equipment that is to be used. These existing tracks are unsealed and have been previously cleared of vegetation and are unlikely to provide habitat to any threatened species.

Flora

The desktop review identified a total of 213 species of flora have been previously recorded within the locality, comprising 156 native and 57 exotic species (BCD 2019a). The Poaceae family is the most diverse family recorded (46 species) followed by Asteraceae (28 species) and Fabaceae (24 species). A full list of flora species known to occur or predicted to occur within the locality is provided in Appendix F.

One threatened flora species, Swainsona recta (Small Purple-pea) has been previously recorded within the locality (BCD, 2019a). This species is listed as endangered under the BC and EPBC Acts. A further five threatened flora species or their habitats are predicted to occur in the locality (DoEE 2019a). Based on known habitat associations and the nature and condition of habitat available, it is unlikely that any threatened flora species would occur within the proposal site.


The desktop review identified that the majority of the proposal site is not mapped as having native vegetation. Despite the majority of the proposal site not being mapped, there is potential for TECs to occur within other areas of the proposal site, particularly the derived grassland vegetation form of White Box Yellow Box Blakely’s Red Gum TEC due to its known occurrence in the locality (DPIE, 2015). Prior to deciding upon potential compound areas or alternative quarries, these areas would be assessed for vegetation cover and potential conformance to this TEC. The existing access tracks and dam structure within the proposal site appear to have been previously cleared and consist of areas with minimal value for potential flora or fauna habitat. These areas appear to be in low condition and are unlikely to conform to a TEC.

A number of Plant Community Types (PCTs) have been mapped within close proximity to the proposal site (refer to Figure 6-2) (Appendix F). Their potential for BC Act or EPBC Act listing as a TEC, are summarised in Appendix F.

Fauna

A total of 227 species of fauna have been previously recorded within the locality, comprising of 219 native species and eight exotic species (BCD 2019a).

Of these 219 native fauna species, a total of 56 of these fauna species are listed under the BC Act and/or the EPBC Act. The species which may have a moderate to high chance of occurrence within the proposal site based on the habitat present are listed in Table 6-8. Nine of the 12 species which may occur within the proposal site are birds, which are highly mobile and are likely to utilise the proposal site as a fly-over, in order to access the adjacent areas of native vegetation within the locality for foraging and roosting. The remaining species are the


Trout Cod (Maccullochella macquariensis), Silver Perch (Bidyanus bidyanus) and the Murray Cod (Maccullochella peelii) which utilise Burrendong Dam itself. These aquatic species are discussed in Section 6.4.

Existing fauna habitat within the proposal site is highly modified due to activities associated with construction and operation of the dam. This is due to the proposal site being utilised for access roads, construction and compound sites. These areas within the proposed site are unlikely to provide important habitat value for native fauna. Better quality fauna habitat is likely to be provided in the adjacent and connected vegetation remnants to the north, west and south of the proposed site (Figure 3-1).

Table 6-8 Summary of fauna species with moderate to high likelihood of occurrence within the proposal site

Scientific name Common name BC Act

EPBC Act

Artamus cyanopterus cyanopterus

Dusky Woodswallow V -

Chthonicola sagittata Speckled Warbler V - Climacteris picumnus victoriae Brown Treecreeper (eastern

subspecies) V -

Glossopsitta pusilla Little Lorikeet V - Haliaeetus leucogaster White-bellied Sea-Eagle V Mi; Ma Maccullochella macquariensis Trout Cod E E Maccullochella peelii Murray Cod - V Bidyanus bidyanus Silver Perch - CE Melanodryas cucullata cucullata Hooded Robin (south-eastern form) V - Motacilla flava Yellow Wagtail - Mi; Ma Rostratula australis Australian Painted-snipe E E; Ma Stagonopleura guttata Diamond Firetail V -

Priority Weeds

Flora species that are listed as priority weeds within the Dubbo Regional LGA have previously been recorded or are predicted to occur in the locality (BCD 2019a; DoEE, 2019a; DPI, 2019a). These weeds are summarised in Table 6-9 and may have the potential to occur within the proposal site.


Table 6-9 Weed species previously recorded in the locality

Scientific name Common name Biosecurity duty (Biosecurity Act)

Asparagus asparagoides Bridal Creeper Prohibition on dealings Must not be imported into the State or sold

Heliotropium amplexicaule Blue Heliotrope Regional Recommended Measure The plant should not be bought, sold, grown, carried or released into the environment.

Lycium ferocissimum African Boxthorn Prohibition on dealings Must not be imported into the State or sold

Nassella trichotoma Serrated Tussock Prohibition on dealings Must not be imported into the State or sold

Opuntia aurantiaca Tiger Pear Prohibition on dealings Must not be imported into the State or sold Regional Recommended Measure Land managers should mitigate the risk of the plant being introduced to their land. The plant should not be bought, sold, grown, carried or released into the environment. Land managers to reduce impacts from the plant on priority assets

Opuntia stricta var. stricta Common Prickly Pear

Pinus radiata Radiata Pine - Rubus fruticosus aggregate Blackberry Prohibition on dealings

Must not be imported into the State or sold

Salix spp. Willow Prohibition on dealings Must not be imported into the State or sold

Tamarix aphylla Athel Pine Prohibition on dealings Must not be imported into the State or sold

BURRENDONG DAM

MUMBIL

YARRAGAL

LAKEBURRENDONG

TARA

ROAD

FASH

IONS

MOUN

TROA

D

STATE

W

ATER

ROAD

THEC

IRCLE

ROAD

YAR

RAGALR

OAD

FIGURE 6.3

0 0.25 0.5 0.75 1

Kilometres


12512398

Date 13/11/2019

WaterNSWBurrendong Dam Deep Water Storage Analysis

Options Analysis Report

Map Projection: Mercator Auxiliary SphereHorizontal Datum: WGS 1984

Grid: WGS 1984 Web Mercator Auxiliary Sphere

Paper Size ISO A4

oData source: sixmaps/LPI_Imagery_Best: © Department of Finance, Services & Innovation 2017. Created by: TMortonN:\AU\Orange\Projects\22\12512398\GIS\Maps\Deliverables\DWSA_Final_0.aprx\12512398_DWSA002_Veg_0

Print date: 13 Nov 2019 - 17:47

Legend

Borrow pit

Project Site

Proposed haul route

Vegetation

Dry SclerophyllForests (Shrubbysubformation)

Forested Wetlands

Grasslands

Grassy Woodlands

Not Native

Semi-arid Woodlands(Shrubbysubformation)

Vegetation Communities



Impacts

The proposal would use existing access tracks that have been cleared. If additional access tracks are required to be constructed for the proposal, biodiversity assessments would be required to determine the ecological values of the potential habitat present and if these are likely to be impacted by the works.

The proposed quarry site has been cleared and vegetation is limited to ground cover that has colonised the site following clearing. For these reasons, the proposed quarry site is unlikely to provide habitat for any threatened biota.

Temporary laydown areas would be required for the proposed works and would be located in existing cleared and disturbed areas, which are devoid of vegetation that would provide minimal habitat value to flora and fauna. The exact location of the laydown areas within the proposal area would be determined by the construction contractor in consultation with WaterNSW. The exact locations of laydown area would be identified in the Construction Environmental Management Plan (CEMP).

Flora

Due to the proposed works being undertaken in existing cleared access tracks and the dam structure itself, it is likely that the proposal would have a negligible impact on flora species within the proposal site. There is potential to introduce diseases such as Phytophthora cinnamomi or Myrtle rust (Austropuccinia psidii) and exotic weeds into the area which may result in indirect impacts on native flora species adjacent to the proposal site. These impacts are key threatening processes (KTPs) and are described in detail in Table 6-10. Provided that the mitigation measures described in Table 6-11 are followed, these impacts are not likely to be substantial.


If any additional compound sites need to be established, these would be located in existing cleared and disturbed areas. If a compound site is to be established in grassland areas there is potential that there could be impacts to the derived native grassland form of White Box Yellow Box Blakely’s Red Gum TEC. A site inspection and biodiversity assessment should be completed for any areas that require vegetation clearing (including grassland areas) in order to assess the presence of any TECs and/or habitat for threatened biota.

As mentioned above, there is potential for disease and exotic species to be introduced as a result of the proposal. The introduction of disease and/or weed species may result in indirect impacts to TECs located within or adjacent to the proposal site. Provided that the mitigation measures described in Table 6-11 are followed, these impacts are not likely to be substantial.

Fauna

Due to the proposed works being undertaken in existing disturbed and cleared tracks and quarries direct impacts to fauna are unlikely to occur. No hollow-bearing, roosting or foraging trees and vegetation are to be removed as a result of the proposal. As such it is unlikely that any direct impact to fauna species would occur.

The proposal also has the potential to result in indirect impacts to some fauna species due to construction works. The operation and subsequent drawdown of the reservoir is likely to reduce the available habitat for species which may rely on large bodies of water, such as migratory and predatory birds. These include the threatened species such as the Australian Painted Snipe (Rostratula australis) and the White-bellied Sea-Eagle (Haliaeetus leucogaster)


which area known to occur in the locality. Due to the highly mobile nature of these species and suitable habitat within the locality, these impacts are not likely to be substantial.

Noise and vibration within the proposal site during construction may discourage some fauna species from utilising adjacent vegetation for foraging and roosting (Section 6.11). This indirect impact would be temporary and is likely to have only a marginal effect on native fauna. Operational noise impacts would be minor and likely to have negligible impact on native fauna.

Key threatening processes

A key threatening process (KTP) is defined under the BC Act as an action, activity, or proposal that:

Adversely affects two or more threatened species, populations or ecological communities.

Could cause species, populations or ecological communities that are not currently threatened to become threatened.

A summary of KTPs associated with the terrestrial elements of the proposed works are listed in Table 6-10. KTPs listed under the Fisheries Management (FM) Act are discussed in detail in Section 6.4 and the Water Quality and Aquatic Ecology Impact Assessment (Appendix D).

Table 6-10 Key threatening processes

KTP Status Comment Alteration to the natural flow regimes of rivers, streams, floodplains & wetlands

BC Act Alteration to the dam levels may impact upon the available foraging and habitat of many fauna species including migratory birds, raptors and fish species.

Infection of native plants by Phytophthora cinnamomi

BC Act; EPBC Act Construction works may introduce disease to the surrounding native vegetation if hygiene protocols are not followed.

Introduction and establishment of Exotic Rust Fungi of the order Pucciniales pathogenic on plants of the family Myrtaceae

BC Act Construction works may introduce disease to the surrounding native vegetation if hygiene protocols are not followed.

Invasion and establishment of exotic vines and scramblers

BC Act Construction works may introduce exotic weed species to proposal site and locality if hygiene protocols are not followed.

Invasion of native plant communities by exotic perennial grasses

BC Act; EPBC Act

Loss and degradation of native plant and animal habitat by invasion of escaped garden plants, including aquatic plants

BC Act; EPBC Act

Downstream terrestrial environments

Operation of the proposal is likely to have beneficial effects on native terrestrial flora and fauna downstream of Burrendong Dam as it would extend water presence within the river and delay a cease to flow event in the section of the Macquarie River between the dam and Warren by three months. A broad range of terrestrial species would benefit from flow being maintained between Burrendong Dam and Warren as this would reduce water stress on vegetation that is along the riparian corridor which may provide habitat for these species. It would also maintain a water source for mobile species to access.



Mitigation measures provided in Table 6-11 should be implemented to minimise potential impacts on biodiversity values.

Table 6-11 Proposed mitigation measures

Impact Mitigation measures Timing Responsibility Indirect impacts to vegetation

To minimise the risk of damage to vegetation outside the boundaries of access tracks/roads, vehicles and machinery would be restricted to designated access roads and tracks

Construction Contractor

Quarries are to be excavated in existing cleared areas where native grass cover is absent. Where grassland is present, and will require clearing, these areas would need to be assessed for vegetation cover and potential conformance to a TEC. Compound areas would be located in cleared and bare ground areas where grass cover is absent to prevent any damage to the surrounding vegetation. Where a compound area needs to be established within grassland vegetation, a suitable qualified ecologist should assess the area prior to the compound establishment.

Weed management and hygiene protocols

All construction plant, equipment and vehicles would be washed down prior to arrival on site

Construction Contractor

Areas of bare ground would be stabilised as soon as possible to minimise the time bare earth is exposed to erosion and weed invasion Declared weed species must be disposed of in accordance with DPI guidelines for the classification of weeds In the event of the presence of any declared priority weeds, manage them in accordance with the requirements of the Biosecurity Act 2015 including the correct disposal of weed contaminated soil and following washdown procedures. Remove weeds immediately and dispose of without stockpiling Dispose of weed-contaminated soil at an appropriate waste management facility Include photos of priority weeds for use by contractors during toolbox talks and site induction

6.6 Topography, geology and soils


The site is located within in the mid to upper reaches of the Macquarie River catchment. Soil landscapes surrounding Burrendong Dam include Mullion Creek, Erudgerie, Red Hill and Burrendong, with Mookerawa the dominate soil landscape. The proposal is adjacent to Mookerawa soil landscapes which occurs on undulating to rolling low hills and hills; relief 50 -


140 m; slopes 8 - 30%, but generally less than 15%. Drainage lines are 800 m - 3000 m apart and are frequently severely gullied. Slope lengths are 500 – 1200 m long. Sheet erosion occurs on lower slopes. The subsoils are sodic and dispersible, and once exposed to free water, they can erode rapidly to develop moderate or even severe gully erosion. (eSPADEv2.0).

No acid sulphate risks have been recorded on or adjacent to the proposal site.


The land surface may be disturbed when establishing the laydown area and access to the proposal site. The laydown areas would be established on existing disturbed areas and would not require significant earthworks. The proposal would use existing access tracks. Construction may potentially lead to erosion and sedimentation of the Burrendong Dam and this risk would be minimised by implementing the measures listed in Table 6-12.

Construction of the coffer dam would require localised ground and soil disturbance to excavate material from an existing quarry and deposit the material within the dam storage reservoir. The quarry has been used as source material to construct and maintain the dam. Risks associated with erosion and sedimentation of the Macquarie River downslope of the quarry would be managed by implementing the erosion and sediment controls in Table 6-12. Topsoil would be stripped and stored next to the excavated section of the quarry, before being respread over the site to rehabilitate the area once the works is completed.

Fuel and oil from the construction plant and the ancillary facilities are potential sources of pollution. Any spills could potentially be transported into the waterway/ nearby drainage systems and impact water quality. Mitigation measures in Table 6-12 would be implemented to reduce the risk of spills occurring that impact on soils.


Mitigation measures for potential geology and soil impacts are provided in Table 6-12.

Table 6-12 Topography, geology and soil mitigation measures

Topography, geology and soils mitigation measures


Erosion and sedimentation

Erosion and sediment controls would be installed prior to the commencement of construction generally in accordance with Landcom (2006) Edition 4 ‘Managing Urban Stormwater: Soils and Construction’ (the Blue Book) and would be maintained until the disturbed area has been stabilised.

Contractor Prior to construction

Weather forecasts shall be checked daily so that expected storm events can be considered for project planning in erosion and sediment management.


Fuel and chemical spills

Spill kits would be available with each refuelling area and all staff would be trained in their use. A spill kit including boom would be accessible to the work area adjacent to the waterway at all times to manage any accidental spills.

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Topography, geology and soils mitigation measures

Spill containment measures (such as drip trays) to be used in refuelling areas. Where possible refuelling would not occur within 40 metres of the reservoir or Macquarie River.


Fuels and oils used on barges would be stored in appropriately bunded areas in accordance with the requirements of relevant Australian Standards, and EPA’s Storing and Handling of Liquids: Environmental Protection – Participants Manual (Department of Environment and Climate Change, 2007).


6.7 Aboriginal heritage


Aboriginal heritage refers to both Aboriginal archaeological sites, and sites or places of cultural value to Aboriginal people. These are protected under the NPW Act as Aboriginal Objects and Aboriginal Places.

The Macquarie catchment forms part of the lands originally occupied by the Wiradjuri, Wailwan and Wongaibon Aboriginal nations. The proposal is located in Wiradjuri land.

A Due Diligence assessment according to the Due Diligence Code of Practice for the Protection of Aboriginal Objects in New South Wales (Due Diligence; DECCW 2010) was completed (refer Appendix F).

A search of the Department of Premier and Cabinet administered Aboriginal Heritage Information Management System (AHIMS) database completed on 10 September 2019 returned three records for Aboriginal heritage sites within a five kilometre by five kilometre search area that centred on the study area (GDA Zone 55, Eastings: 629500–702500, Northings: 6381500–6386500 with no buffer).

There are two site types recorded on the AHIMS database in the search area: two are artefact scatters and one is subject to information restriction by the Wellington Valley Wiradjuri Aboriginal Corporation. The AHIMS registrar and the Wellington Valley Wiradjuri Aboriginal Corporation were both contacted requesting the restricted site information on Wednesday 11 September 2019.

The restricted site is outside the area that would be affected by construction of the proposal.

The two recorded Aboriginal sites are located about 500 metres from the proposal site.

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Figure 6‐4 has been deleted from this version of the REF as it contains restricted site

information

Figure 6-4 Previously recorded sites in relation to the study area


Construction of the proposal would be limited to areas that were substantially modified during construction of Burrendong Dam between 1949 and 1965 and the landscape changes remain ‘clear and observable’.

Potential impacts could result from the uncovering of previously unidentified Aboriginal cultural heritage places or items. There is a low likelihood of there being subsurface archaeological deposits within the proposal site as it has been substantially modified by previous construction activities.

As the proposal would be limited to existing disturbed land and would not impact on the two Aboriginal sites that are recorded on AHIMS, impacts on Aboriginal sites are unlikely and an Aboriginal Heritage Impact Permit is not required.



Mitigation measures for potential impacts on Aboriginal heritage are provided in Table 6-13.

Table 6-13 Aboriginal heritage mitigation measures

Aboriginal heritage mitigation measures


Laydown areas to be sited on existing disturbed land Contractor During construction

Machinery used for the proposed work must remain within the impact footprint, or on established tracks or vehicle areas.


Inductions for staff undertaking the proposed work must explain the legislative protection requirements for all Aboriginal sites and objects in NSW and the relevant fines for noncompliance. Staff should be briefed on the location of the restricted AHIMS site and artefact scatters. .


If any Aboriginal object as defined in the NPW Act is encountered within or immediately adjacent to the work area, work shall stop immediately until the significance of the item can be established. WaterNSW Procedure CD2012/184* - Unexpected Aboriginal Objects Procedure should be followed and this involves notifying the Department of Premier and Cabinet in accordance with the NPW Act.


If human skeletal remains are encountered during construction all work in that area must cease and the Police would be notified immediately.


6.8 Historic heritage


A desktop search of historic registers including the World Heritage List, National Heritage List, Commonwealth Heritage List, the Register of National Estate (non-statutory archive), NSW State Heritage Register, WaterNSW’s Section 170 Heritage and Conservation Register and the heritage schedules of the Wellington LEP. Searches revealed that no world, national Commonwealth; state or local heritage items occur within the proposal area.

The dam is listed on the WaterNSW Section 170 Heritage and Conservation Register (S170 Register) so a Statement of Heritage Impact (SOHI) has been prepared for the proposal. The dam was recommended for listing on the Wellington Local Environment Plan (LEP) but is currently not listed in Schedule 5 of the Wellington LEP (2012).

The S170 Register lists that Burrendong Dam is locally significant in respect of:

Its impact to the local economy and agriculture (Criteria a)

Its aesthetic value within the landscape and its use as a source of recreation (Criteria c)


Employment opportunities it provides to the local area (Criteria d)

Items of historic value under the water storage such as the former village of Burrendong and potential relics from gold field activities (Criteria e)


Construction

As the proposal would be within the existing dam area, no permanent impact on known historical heritage is expected to occur. Impact to previously unknown historical items during construction is also very unlikely, due to the proposal footprint sitting within the existing dam storage area. Aesthetics of the dam would be impacted during the construction phase due to the presence of plant equipment and construction activity. This impact is assessed to be minor as the works are temporary and construction is scheduled to occur in a relatively short timeframe due to the urgent need of the proposal.

WaterNSW is required to follow procedures and guideline set out in The State Agency Heritage Guide: Management of Heritage Assets by NSW Government Agencies (Heritage Office of NSW, 2005):

3.25: Adaption: adaptation should be limited to that which is essential for the use of the heritage asset. Adaptation should occur where the adaptation has minimal impact on the heritage significance of the heritage asset. Adaptation should involve minimal change to significant fabric, and should be undertaken only after demonstrated consideration of alternatives.

3.28 Reversibility of Works: alterations or extensions which do not contribute to the conservation of a heritage asset should be undertaken is such a way that they are reversible where practical.

Operation

The operation phase would not impact upon known historical heritage items including the dam, however it would impact on the reservoir that is impounded by the heritage listed dam. The proposal would be decommissioned if large inflows are predicted and this would involve removing all infrastructure other than the coffer dam, the concrete pads required for the pipeline junctions and the compressor building for the aeration system. The presence of coffer dam, concrete pads and compressor building would result in a minor effect on the historic aesthetic of the dam, however this infrastructure would be viewed in the context of the existing water supply infrastructure at the site. Overall the proposal is expected to have a positive impact on the dam’s cultural significance to the local area is it will allow for continued function of the dam toward the purpose for which it was built and for which it has been listed on the S170 Register.



Mitigation measures for potential impacts on Historic heritage are provided in Table 6-14.

Table 6-14 Historic Heritage mitigation measures

Historic Heritage Mitigation Measures

Impact Mitigation required Responsibility Timing

Damage to unknown significants subsurface historic deposits or items

Confine construction work to the already disturbed area of the dam footprint.

Induct construction teams as to take care and due diligence in relation to unanticipated finds of historical items.

Follow the Unanticipated Finds Protocol outlined in Appendix 4 of the Statement of Heritage Impact Report (OzArk, 2019).

Construction contractor

Construction, decommissioning

6.9 Socio-economic


The Macquarie Valley covers more than 75,000 square kilometres and extends from the Blue Mountains to the Barwon River Plains. Burrendong Dam provides water supply to towns and cities that include Dubbo, Wellington, Narromine, Warren, Nyngan and Cobar, and to meet customer orders, including downstream irrigators and industry It also supplies high security water to users such as mines, Western Plains Zoo at Dubbo, permanent plantings, gold clubs and abattoirs.

According to the 2016 Census:

Dubbo urban centre and locality had a population of 34,339

Narromine urban centre and locality had a population of 3,528

Warren urban centre and locality had a population of 1,530

Cobar urban centre and locality had a population of 3,748

Nyngan urban centre and locality had a population of 1,988

Wellington urban centre and locality had a population of 4,519.

Each of these urban areas are surrounded by rural areas that include small towns and villages that access the larger population centres for a range of educational, social, employment and medical services.



The proposal is the third of a three stage strategy that is being implemented to delay a cease to flow event in the Macquarie River downstream of Burrendong Dam by about seven months to May 2020. The proposal involves works to Burrendong Dam and the beneficial impacts of delaying a cease to flow event will be experienced by the towns and communities along the Macquarie River that rely on releases from Burrendong Dam for a large proportion of their water supply, including Dubbo, Wellington, Narromine, Warren, Nyngan and Cobar. These towns will benefit because the proposal will extend the period of time that the Macquarie River is able to be operated to deliver the water that is currently in storage to towns and high security users. Delaying a cease to flow event provides time for inflows to occur and increase the supply. It also provides time for additional emergency water supply measures to be implemented, including but not limited to the expansion of Dubbo Regional Council’s groundwater supply system which is scheduled to be completed by May 2020.

The proposal is being implemented as part of a strategy under the Macquarie-Castlereagh IRG that will prioritise water to communities for critical human need (section 2.1.2). Critical human need refers to the minimum amount of water needed to meet basic human needs. It also includes non-human needs, where a failure to meet these needs would cause too much damage to social, economic or national security.

Consultation has been undertaken (refer section 5.2.2) with community and stakeholders to understand water allocation requirements. This reflects that the ROSCCo meeting supported implementation of the proposal.

The proposal would draw down the storage level in the dam and this would reduce the area that is available for recreational activities such as fishing and boating. This impact would be temporary and the surface area that is available for recreation would progressively increase as storage levels rise in response to inflows.


Mitigation measures for potential socio-economic impacts are provided in Table 6-15.

Table 6-15 Socio-economic mitigation measures

Socio-economic mitigation measures

Impact Mitigation required Responsibility Timing

Reduced water availability

Ongoing consultation with water users downstream of the proposal to minimise impacts of reduced water flow. Impacts would be managed and management measures communicated.

WaterNSW (ROSCCo)

Operation

WaterNSW will continue to publish media releases and operations updates for the Macquarie Valley on its website (https://www.waternsw.com.au/supply/drought-information/regional-nsw/macquarie-valley)

WaterNSW Operation

WaterNSW will continue to work with the NSW government and relevant agencies to implement drought contingency measures to ensure water is available for users that rely on water within the Macquarie River Catchment.

WaterNSW Operation

https://www.waternsw.com.au/supply/drought-information/regional-nsw/macquarie-valley

https://www.waternsw.com.au/supply/drought-information/regional-nsw/macquarie-valley


6.10 Air quality


Air quality in the proposed area would be typical of the surrounding rural region and generally be of a high quality. There are no significant point sources of air pollution in the vicinity of the proposal site. Dust is the main factor that would contribute to a reduction in air quality, particularly given the prolonged drought.


Construction

Particulate emissions would be the principal air contaminate generated by the proposed activities. The main sources would be from:

Extracting rock from the quarry area

Sieving/ sorting of rock/soil at the quarry

Crushing rock

Transporting rock along unsealed roads to proposal site

The proposal requires minor earthworks to construct the coffer dam and traffic movements over unsealed areas that have the potential to generate dust. The works would be in areas characterised by rural land uses and have few sensitive receivers. Dust generated by vehicles passing over unsealed tracks is a common occurrence in the locality and the proposal would have negligible additional impacts provided mitigation measures listed in Table 6-16. Potential impacts on air quality are unlikely to be significant and would be localised and limited to the construction and decommissioning periods. Exhaust emissions from vehicles, plant and machinery are considered likely to have negligible impact on regional air quality. These emissions would be small in volume and readily dispersed by prevailing winds.

Operation

Operation of the proposal would have negligible air quality impacts. There would be infrequent impacts associated with dust generation and emissions from maintenance vehicles using unsealed tracks to access the structures. Exhaust emissions would be small in volume and readily dispersed by prevailing winds.

The proposal would draw down the water level and this would expose additional land. There is the potential for dust to be generated as wind passes over the exposed land. This impact would be temporary and minor because the additional area exposed would be a very small proportion of the overall extent of exposed ground surfaces in the locality that have the potential to be a source of dust during the current drought.


Mitigation measures for potential air quality impacts are provided in Table 6-16.

Table 6-16 Air quality mitigation measures

Air quality mitigation measures

Mitigation required Responsibility Time

All reasonable and feasible measures would be undertaken to minimise dust impacts from the construction



Air quality mitigation measures

works, including when crushing, grinding or separating material obtained from the quarry area

Covering of trucks during transport to and from the proposal site.


Minimise works during windy periods to minimise dust generation.


Ensure all plant and equipment complies with part 4 of the Protection of the Environment Operations (Clean Air) Regulation 2002.


Construction vehicles and equipment are to be suitably serviced within the six-month period prior to commencement of construction activities and all necessary maintenance undertaken during the construction period. The excessive use of vehicles and powered construction equipment is to be avoided.


Enforce speed limits of no more than 40 km/hr on unsealed access tracks to the site.


All construction machinery is to be turned off when not in use to minimise emissions.


6.11 Noise and vibration


Receivers

The background noise environment is typical of a rural area. Background noise levels are expected to be low and the main existing noise sources in the vicinity of the proposed deep water storage access works would be associated with traffic on the road network and operation of agricultural plant and machinery.

Based on aerial imagery, the project location and associated works would be in the vicinity of the noise sensitive receivers listed in Table 6-17 and shown on Figure 6-5.

#0

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#0

#0

#0

#0

#0

#0

#0

R1

R2

R3

R4

R5

R6

R7

R8

R9

MUMBIL

YARRAGAL

YARRABIN

LAKEBURRENDONG

FASHION

SMOUNTROAD

STATE

WAT

ERROAD

TARAROAD

THE C

IRCLE RO

AD

YARRAG

AL

ROAD

FIGURE 6.6

0 0.3 0.6 0.9 1.2

Kilometres


12512398

Date 29/10/2019

Water NSWBurrendong Dam Deep Water Storage Analysis



Paper Size ISO A4

oData source: sixmaps/LPI_Imagery_Best: © Department of Finance, Services & Innovation 2017. Created by: fmackayN:\AU\Orange\Projects\22\12512398\GIS\Maps\Deliverables\DWSA_0.aprx\12512398_DWSA003_NoiseRecievers_0

Print date: 29 Oct 2019 - 09:02

Legend

Project Site

Cadastre

Proposed haul route

Borrow pit

#0 Receivers

Proposal site details andnearby sensitive receivers


Table 6-17 Identified sensitive receivers

ID Name Category Approximate distance from site (m)

R1 WaterNSW workshop Industrial 700

R2 WaterNSW office Commercial 900

R3 Ridgecrest Christian Education & Convention Centre

Passive recreation area 1,200

R4 Ridgecrest Education Educational institute 1,900

R5 Reflections Holiday Park Passive recreation area 1,900

R6 Lake Burrendong State Park Passive recreation area 2,000

R7 Burrendon Botanic Garden and Arboretum

Passive recreation area 3,000

R8 Lake Burrendong Sport and Recreation Centre

Active recreation area 4,000

R9 Resident Residential 2,500 (from quarry)

Figure 6-6 shows the proposal site location and the identified receivers.

Background levels

In the absence of any measured background noise data, the background noise level for the proposal site is adopted from the recommendations provided in the NSW Noise Policy for Industry (NPI) (EPA, 2017). The NPI provides detailed methodology to determine the Rating Background Level (RBL). A summary of the adopted RBLs for this assessment is shown in Table 6-18. These are the minimum recommended RBL in the NPI.

Table 6-18 Recommended RBL

Period Recommended RBL dB(A) Day 35 Evening 30 Night 30

Note: Day time: 7:00 am to 6:00 pm Monday to Saturday; or 8:00 am to 6:00 pm on Sundays and Public Holidays. Evening: 6:00 pm to 10:00 pm. Night time: remaining period (NSW Noise Policy for Industry (NPI), 2017)


6.11.2 Criteria

Construction noise criteria – General

Construction noise criteria were developed in accordance with the ICNG (DECC, 2009) for each noise catchment area. Standard hours defined in the guideline are:

7:00 am to 6:00 pm Monday to Friday

8:00 am to 1:00 pm on Saturday

No work on Sundays or public holidays

The proposed construction activities are expected to occur beyond the standard construction hours. With the potential to have construction occurring 24 hours a day, 7 days a week to meet their required timeframes.

The ICNG acknowledges that the following activities can be justified to be conducted outside the recommended construction hours:

The delivery of oversized plant or structure.

Emergency work.

Works for which it can be demonstrated that there is a need to operate outside the recommended standard hours.

Works which maintain noise levels at receivers below the night time noise affected construction noise management levels.

For recommended standard hours, the following terms are used in relation to establishment of construction noise criteria:

The ‘noise affected level’ represents the point above which there may be some community reaction to noise. For standard construction hours this level is established with reference to the measured rating background level (RBL) (described in Table 2-3) plus 10 dB(A). Outside standard construction hours this level is the RBL plus 5 dB(A).

The ‘highly noise affected level’ represents the point above-which there may be strong community reaction to noise. This level is set at LAeq(15min) 75 dB(A).

The construction noise management levels (CNMLs) that apply to sensitive receivers in the vicinity of the project during construction of the proposed deep water storage access are presented in Table 6-19.

Table 6-19 ICNG CNMLs at identified receivers, dB(A)

Receiver Type ICNG Management Level LAeq(15min) dB(A)

Highly affected noise level

During standard construction

hours

Outside standard construction hours (day1)

Outside standard construction

hours (evening/night2)

Residential (Rural) 75 45 40 35

Commercial - offices N/A 70+ 70+ 70+

Industrial N/A 75+ 75+ 75+

School N/A 45 dB(A) Internal+

45 dB(A) Internal+

45 dB(A) Internal+


Receiver Type ICNG Management Level LAeq(15min) dB(A)

Highly affected noise level

During standard construction

hours

Outside standard construction hours (day1)

Outside standard construction

hours (evening/night2)

Active recreation N/A 65+ 65+ 65+

Passive recreation N/A 60+ 60+ 60+ 1 Outside standard construction hours (day) is defined as 7:00 am to 8:00 am and 1:00 pm to 6:00 pm on Saturdays, 8:00 am to 6:00 pm Sundays and public holidays. 2 Outside standard construction hours (evening/night) is defined as 6:00 pm to midnight and midnight to 7:00 am Monday to Friday, 6:00 pm to midnight and midnight to 8:00 am Saturdays, 6:00 pm to midnight and midnight to 8:00 am on Sundays and public holidays. + Noise management level only applicable when in use.

Operational noise criteria - Project noise trigger level

The Noise Policy for Industry (EPA, 2017) provides guidance on the assessment of operational noise impacts. Operational noise impacts from a development is assessed against a project noise trigger level that, if exceeded, indicates a potential noise impact on the community. The project noise trigger level is the lower value of the intrusiveness noise level and the amenity noise level.

The intrusiveness noise level aims to protect against significant changes in noise levels. Typically, this will be the project noise trigger level in areas with low existing background noise levels. The intrusiveness noise level is determined by a 5 dB(A) addition to the measured background noise level. The NPI (EPA, 2017) recommends that the intrusive noise criteria for the evening period should not exceed the day-time period and the night-time period should not exceed the evening period. The intrusive noise criteria are only applicable to residential receivers.

The recommended amenity noise level is the noise level objective for total industrial noise at a receiver and are determined based on the overall acoustic characteristics of the receiver area, the receiver type and the existing level of industrial noise. The area near the proposed is considered to be rural due to the following characteristics:

Residential receivers are located in isolated dwellings;

There is minimal road traffic noise in the area;

Area is expected to have low background noise levels.

The project specific noise trigger levels taking into account intrusiveness and amenity criteria are provided in Table 6-20.

Table 6-20 Noise Policy for Industry (NPI) Project noise trigger levels

Receiver type Time of day

Intrusiveness noise level

LAeq(15 min), dB(A)

Recommended amenity noise level

LAeq(15 min), dB(A)

Project noise trigger level

dB(A)

Residential – Rural

Day 40 48 40

Evening 35 43 35

Night 35 38 35

Commercial When in use

- 65 65


Receiver type Time of day

Intrusiveness noise level

LAeq(15 min), dB(A)

Recommended amenity noise level

LAeq(15 min), dB(A)

Project noise trigger level

dB(A)

Industrial When in use

- 70 70

School Classroom - internal

Noisiest 1-hour when in use

- 35* 35

Holiday accommodation

Day - 53 53

Evening - 48 48

Night - 43 43

Passive recreation

When in use

- 50 50

Active recreation When in use

- 55 55

*Internal noise criteria

Road traffic criteria

The Road Noise Policy (RNP) (DECCW, 2011) provides traffic noise criteria for residential receivers in the vicinity of existing roads (Table 6-21). The criteria is applied to operational and construction traffic on public roads to identify potential road traffic impacts and the requirement for feasible and reasonable mitigation measures.

The RNP application notes state that “for existing residences and other sensitive land uses affected by additional traffic on existing roads generated by land use developments, any increase in the total traffic noise level as a result of the development should be limited to 2 dB above that of the noise level without the development. This limit applies wherever the noise level without the development is within 2 dB of, or exceeds, the relevant day or night noise assessment criterion.”

If road traffic noise increases due to construction or operation are within 2 dB(A) of current levels then the objectives of the RNP are met and no specific mitigation measures are required.

Table 6-21 Road traffic noise criteria, LAeq(period), dB(A)

Type of Development Day

7:00 am to 10:00 pm

Night 10:00 pm to

7:00 am Existing residence affected by additional traffic on arterial roads generated by land use developments 60 Leq(15 hour) 55 Leq(9 hour)

Existing residence affected by additional traffic on local roads generated by land use developments 55 Leq(1 hour) 50 Leq(1 hour)

Vibration criteria

Human comfort

Vibration criteria for human comfort have been established with consideration to the, Assessing Vibration: A Technical Guideline (AVTG) (February 2006) for guidance on human exposure to vibration.


The AVTG separates sources of vibration into continuous, impulsive and intermittent and explains that each category should be assessed differently. Vibration from construction work, passing heavy vehicles, and piling is provided as an example of an intermittent source of vibration which is to be assessed using the vibration dose value (VDV) method.

While the AVTG recommends that for intermittent vibration VDV is used as the primary indicator for human comfort, the British Standard BS 5228-2:2009 Code of practice for noise and vibration on construction and open sites – Part 2: Vibration guidance can be used as an additional indicator of perceptibility. BS 5228-2 recommends the guidance values presented in Table 6-22. These values are often more suitable for construction works as available information for construction activities and equipment is typically in the form of a peak particle velocity value rather than a dose value.

Table 6-22 Guidance on effects of vibration levels

Vibration Level Effect

0.14 mm/s Vibration might be just perceptible in the most sensitive situations for most vibration frequencies associated with construction. At lower frequencies, people are less sensitive to vibration.

0.30 mm/s Vibration might be just perceptible in residential environments.

1.00 mm/s It is likely that vibration of this level in residential environments will cause complaint, but can be tolerated if prior warning and explanation has been given to residents.

10.0 mm/s Vibration is likely to be intolerable for any more than a very brief exposure to this level.

Cosmetic damage

Vibration criteria for cosmetic damage have been established with consideration to:

British Standard BS 7385:1993 Evaluation and Measurement for Vibration in Buildings – Part 2: Guide to Damage Levels from Ground Borne Vibration for guidance on cosmetic damage to residential buildings.

German Standard DIN 4150-3: 2016 Vibrations in buildings – Part 3: Effects on structures for guidance on cosmetic damage to heritage buildings.

BS 7385:1993 provides guidance on vibration level likely to cause cosmetic damage to residential buildings or reinforced structures. The British Standard and German Standard guide is reproduced below in Table 6-23 and Table 6-24, respectively.

Table 6-23 Transient vibration guide for cosmetic damage (BS 7385:1993)

Type of building Peak component particle velocity in frequency range of predominant pulse

4 Hz to 15 Hz 15 Hz and above Unreinforced or light framed structures Residential or light commercial type buildings

15 mm/s at 4 Hz increasing to 20 mm/s at 15 Hz

20 mm/s at 15 Hz increasing to 50 mm/s at 40 Hz and above

Reinforced or framed structures Industrial and heavy commercial buildings

50 mm/s at 4 Hz and above


Table 6-24 Guideline values for short term vibration on structures (DIN 4150-3)

Type of structure

Guideline values for velocity, vi(t)1 (mm/s)

1 Hz to 10 Hz

10 Hz to 50 Hz

50 Hz to 100 Hz2

Buildings used for commercial purposes, industrial buildings, and buildings of similar design 20 20 to 40 40 to 50

Dwellings and buildings of similar design and/or occupancy 5 5 to 15 15 to 20

Structures that, because of their particular sensitivity to vibration, cannot be classified under lines 1 and 2 and are of great intrinsic value (for example heritage listed buildings)

3 3 to 8 8 to 10

Notes:

1. The term vi refers to vibration levels in any of the x, y or z axes

2. At frequencies above 100 Hz the values given in this column may be used as minimum values

Guidelines for buried pipework and services

The British Standard BS 7385-2:1993 Evaluation and measurement for vibration in buildings notes that structures below ground are known to sustain higher levels of vibration and are very resistant to damage unless in very poor condition.

Guideline values for vibration to evaluate the effects of vibration on buried pipework is provided in DIN 4150-3. These values are reproduced in Table 6-25.

Table 6-25 Guideline values for vibration effects on buried pipework

Line Pipe material Guideline values for vibration velocity measured on the pipe

1 Steel (including welded pipes) 100 mm/s 2 Clay, concrete, reinforced concrete, pre-stressed

concrete, metal (with or without flange) 80 mm/s

3 Masonry, plastic 50 mm/s

Note that in general, compliance with the guideline values for structural damage would result in compliance with the guideline values for buried pipework.

Blasting

No blasting is anticipated during construction of the proposal and therefore is not discussed further in this assessment.

6.11.3 Assessment of potential impacts

Construction noise impact assessment

The equipment anticipated to be used for each construction scenario is summarised in Table 6-26.

Although it is highly unlikely that all construction equipment would be operating at their maximum sound power levels at any one time, the assessments for the proposed works assumes that all equipment associated to an activity/scenario are operating simultaneously. This approach has been adopted to identify worst case impacts and any associated mitigation measures.


Table 6-26 Construction equipment sound power levels

Scenario Equipment name Sound power level,

dB(A)1

Qty Adopted Sound Power Level, dB(A)

1 Planning, mobilisation and preparation.

40t Excavator (long reach) 105 1

110 Hand tools 102 1 Heavy vehicles 107 1 Light vehicles 78 2

2 Pipeline installation 40t Excavator (long reach) 105 1

115

Roller compactor 101 1 Grader 110 1 20t Franna Crane 104 1 Water cart 101 1 Heavy vehicles 107 1 Light vehicles 78 3 Hand tools 102 3

3 Cofferdam construction 40t Excavator (long reach) 105 2

114

Generator 102 1 90t Slew Crane 99 1 Hand tools 102 3 Heavy vehicles 107 2 Light vehicles 78 3

4 Aeration and pumping system construction

Pump 97 1

113

Generator 108 1 Compressor 101 1 40t Excavator (long reach) 105 1 90t Slew Crane 99 1 Heavy vehicles 107 1 Light vehicles 78 1 Hand tools 102 1

5 Site clean-up, stabilisation and restoration

40t Excavator (long reach) 105 1

110 Hand tools 102 1 Heavy vehicles 107 1 Light vehicles 78 2

6 Compounds/Laydown areas 40t Excavator (long reach) 105 1 110 Heavy vehicles 107 1

Generator 102 1 7 Quarry Operations Heavy Vehicles (Lorry 44 t) 111 2

126

Light Vehicles 78 1 Dozer (20t) 109 1 Rock Crusher and Screen 124 1 Excavator (45 t) 119 1 Front End Loader 110 1

1 Equipment sound power levels are sourced from RMS Estimator (March 2017) and BS5228-2009


Prediction of the construction noise impact to nearby noise sensitive receptors has been performed using RMS’s Construction Noise Estimator (March 2017). Table 6-25 summarises the distance from the construction activity, where sensitive receivers located within that distance would exceed the corresponding management level. The predicted values presented in Table 6-27 are based on the assumptions that:

There is no effective barrier between the proposal site and the nearest noise sensitive premises;

The construction equipment would be operating continuously at full capacity for the full 15-minute evaluation period which is very unlikely in the actual construction site;

All the construction equipment will be operating simultaneously to estimate the worst-case condition, which is unlikely to occur during actual construction.

The construction equipment would not generate any annoying characteristics (low frequency, tonality, impulsiveness, etc.)

Based on readily available aerial imagery, there are a variety of sensitive receivers near the construction site. The nearest identified sensitive receiver is 800 metres from the proposal site. No sensitive receivers are expected to exceed their corresponding construction noise management levels. While no adverse noise impacts are anticipated due to construction of the proposal, general mitigation measures are provided in section 6.11.4 to minimising emissions.

The nearest identified sensitive receiver to the quarry is a residential receiver, which is 2.5 kilometres (North-west) away. The operation of the quarry is intended to be short term, with operations to be completed within two to four weeks. Although the quarry may impact sensitive receivers (active/passive recreation), if/when they are in use, this will be a short term impact.

If construction activities are to take place outside of standard construction hours, it is recommended that the management measures listed in Table 6-33 are considered. The below section covers considerations to help determine sleep disturbance due to construction activities.


Table 6-27 Noise impact distances

Activities Residential Receivers Commercial Receivers (70 dB(A))

Industrial Receivers (75 dB(A))

Education Receiver (45 dB(A))

Passive Recreation Areas (60 dB(A))

Active Recreation Areas (65 dB(A))

Outside of standard hours (evening/ night) (35 dB(A))

Outside of standard hours (day) (40 dB(A))

Construction Noise Management Level (45 dB(A))

Highly Affected Level (75 dB(A))

1 – Planning, mobilisation and preparation

< 600 m < 390 m < 280 m < 13 m < 23 m < 13 m < 280 m < 80 m < 40 m

2 – Pipeline installation

< 850 m < 570 m < 390 m < 23 m < 35 m < 23 m < 390 m < 130 m < 80 m

3 – Cofferdam construction

< 800 m < 560 m < 380 m < 22 m < 30 m < 22 m < 380 m < 120 m < 70 m

4 – Aeration and pumping system construction

< 750 m < 520 m < 350 m < 19 m < 26 m < 19 m < 350 m < 110 m < 60 m

5 – Site clean-up, stabilisation and restoration

< 580 m < 390 m < 280 m < 13 m < 23 m < 13 m < 280 m < 80 m < 40 m

6 – Compound/ Laydown areas

< 600 m < 390 m < 280 m < 13 m < 23 m < 13 m < 280 m < 80 m < 40 m

7 – Quarry operations

< 1800 m < 1300 m < 900 m < 85 m < 140 m < 85 m < 900 m < 300 m < 200 m

Contours illustrating the Noise impact zone are presented in figures in Appendix G.


Construction Sleep Disturbance

The ICNG recommends that where construction works are planned to extend over more than two consecutive nights, maximum noise levels and the extent and frequency of maximum noise level events exceeding the RBL should be considered. In line with the ICNG, further guidance is taken from the NSW Environmental Criteria for Road Traffic Noise (ECRTN, Environment Protection Authority 1999).

To assess the likelihood of sleep disturbance, an initial screening level of (LAmax or LA1(1min) ≤ LA90(15min) + 15 dB(A) is used. In situations where this results in an external screening level of less than 55 dB(A), a minimum screening level of 55 dB(A) is set.

Where there are noise events found to exceed the initial screening level, further analysis is made to identify:

The likely number of events that might occur during the night assessment period

Whether events exceed and ‘awakening reaction’ level of 55 dB(A) LAmax (internal) that equates to NML of LA1(1min) 65 dB(A) (assuming open windows).

If heavy vehicle movements occur during the 10 pm to 7 am night-time period, guidance on the potential for sleep disturbance, the RNP refers to Practice Note 3 of the ENMM for specific impacts from road traffic. The ENMM recommends an evaluation of the number and distribution of night-time pass-by events where the LAFmax – LAeq(1hr) difference is greater than 15 dB, and the maximum noise level of that event is greater than 65 dB LAmax.

Operational noise impact assessment

Acoustic modelling was undertaken using Computer Aided Noise Abatement (CadnaA) version 2019 MR2 to predict the operational noise levels at identified sensitive receivers within the study area. CadnaA is a computer program for the calculation, assessment and prognosis of noise propagation. CadnaA calculates environmental noise propagation according to the ISO9613 noise prediction algorithm. General model setup parameters are described in Table 6-28.

Table 6-28 General Operational Noise Model Inputs and Assumptions

Inputs/assumptions Data incorporated into noise model

Noise model CadnaA version 2019 MR2

Prediction algorithm General: ISO 9613

Terrain No terrain

Receiver heights 1.5 m above building ground level

Noise contour grid spacing 10 m

Ground absorption A ground absorption value of G = 0.7 was applied across the model. An absorption value of G = 0 was applied for bodies of water.

Table 6-29 lists the indicative equipment and their associated sound power levels for the proposal.


Table 6-29 Operational noise sources

Equipment Quantity Operation Cycle SWL+

Pumps (450 kW) 6 Continuous 92 dB(A) Centrifugal air compressor (132 kW) 1 Continuous 72 dB(A) Generator (1MVA) 1 Continuous 121 dB(A)

+Sound power data sourced from Engineering Noise Control Design v 4.3

Table 6-30 shows the predicted project contribution value at the three nearest identified sensitive receivers. Compliance at these receivers implies compliance at other sensitive receivers located further from the proposal site.

Table 6-30 Predicted operational noise impact

Receiver Project noise trigger level, LAeq(15min) dB(A)

Predicted contribution noise level, LAeq(15min)

dB(A) WaterNSW workshop 70 47 WaterNSW office 65 43 Ridgecrest Christian Education & Convention Centre 50 40

Ridgecrest Education 35 35 Reflections Holiday Park 431 34 Lake Burrendong State Park 50 34 Burrendon Botanic Garden and Arboretum 50 27

Lake Burrendong Sport and Recreation Centre 55 22

Resident 351 24 1 The night time period criteria is used as it is the most stringent period.

The site is surrounded by Lake Burrendong, Macquarie River and Cudgegong River, which can be used for recreational (active and passive) purposes, however for the purposes of this assessment has not been identified as a sensitive receiver.

Sleep disturbance

No sleep disturbance noise impacts are predicted as the predicted noise levels at all residential receivers are below the screening criteria of LAeq(15 min) 40 dBA.


Annoying Characteristics

One third octave data was not available to assess for annoying characteristics. If noise complaints attributable to the proposal are received during operation, WaterNSW would consider whether monitoring should be conducted to identify any annoying characteristics (such as tonality, low frequency, impulsiveness, etc.) generated by the proposal. Presence of annoying characteristics would need to have corrections factors applied, as per the NPI, to the measured contribution level at the sensitive receiver.

Traffic noise impact assessment

Entry to the dam and project site is along The Cir Road which connects to Burrendong Way. Heavy vehicles transporting material from the quarry to the dam will be using The Cir Road and surrounding access tracks.

Construction

The anticipated peak one hour traffic generated by the construction works would be at the start and end of the day. The indicative volumes during that time are:

Burrendong Dam site

– 15 light vehicle movements – 4 heavy vehicle movements (2 heavy vehicles in and out)

Quarry site

– 4 heavy vehicle movements (2 heavy vehicles in and out) Existing traffic counts for the area are not available and it is assumed that the existing traffic volumes on The Cir Road is low, and that the noise generated by the additional construction traffic will cause an increase of greater than 2 dB over existing levels.

Although nearby sensitive receivers are active recreational areas and a convention centre that offers accommodation, mitigation measures in section 6.11.4 will be implemented to minimise noise impacts:

Operation

Operation of the proposal is expected to generate a small increase in the number of vehicle movements on nearby roads associated with maintenance activities. As such, traffic noise impact is anticipated to be negligible.

Vibration impact assessment

Construction

Exact details of the equipment sizing and type would be confirmed by the contractor during construction planning. For reference, an extract of the safe working buffer distances to comply with human comfort and cosmetic damage for standard dwellings were sourced from the Construction Noise and Vibration Strategy (Transport for NSW, 2018) and provided in Table 6-31. Note that construction will require use of other plant and equipment, but excavators and vibratory rollers are some of the typical equipment that generate the most vibration.


Table 6-31 Vibration safe working distances

Activity Approx. size/weight/model

Human comfort (OE&H Vibration

Guideline)

Cosmetic damage in Standard

dwelling (BS 7385)

Vibratory Roller 1-2 tonne 15 m to 20 m 5 m 2-4 tonne 20 m 6 m 4-6 tonne 40 m 12 m 7-13 tonne 100 m 15 m

13-18 tonne 100 m 20 m > 18 tonne 100 m 25 m

Small Hydraulic Hammer 300 kg (5 to 12 t excavator)

7 m 2 m

Medium Hydraulic Hammer 900 kg (12 to 18 t excavator)

23 m 7 m

Large Hydraulic Hammer 1600 kg (18 to 34 t excavator)

73 m 22 m

Pile Driver - Vibratory Sheet piles 20 m 2 m to 20 m Jackhammer Handheld Avoid contact with

structure 1 m

These safe working distances are indicative only and may vary depending on the specific equipment used and the ground conditions. Based on the indicative type of equipment that is likely to be used for construction and the distance between construction areas and receivers, it is not expected that there will be vibrational impacts on nearby sensitive receivers.

Operational

Given the large distances between the proposed operational equipment and the nearest sensitive receivers, vibration impacts are not expected during operation of the proposal.


Construction and operational noise impacts are predicted to be under the corresponding limits and therefore mitigation measures are not required.

However, where reasonable and feasible, mitigation and management measures should be implemented to reduce the impact of the construction on nearby receivers. Table 6-32 summarises mitigation and management measures that should be implemented.

Table 6-32 Construction mitigation and management measures

Action required Mitigation measure

Staff training • All personnel working at the site would be made aware of their responsibilities in minimising noise and adhering to the specified work hours

• When not in use, vehicles and machinery will be turned off. • Where practical, machines will be operated at low speed or power. Haulage

and delivery trucks to limit compression braking and heavy throttling in the area. They will be switched off during loading and unloading operations.

Equipment selection

• Use quieter and less vibration emitting construction methods/equipment where reasonable and feasible.

• Minimise the use of tonal reversing beepers on mobile plant. It is recommended to use equipment installed with broadband reversing alarms instead.

• Pneumatic equipment is traditionally a problem – select super silenced compressors, silenced jackhammers and damped bits where possible.


Action required Mitigation measure

Safe working distances

• Place as much distance as possible between the plant or equipment and the receivers

Community Engagement

• Receivers within 600 metres of the proposed works will be notified of the construction details of the project. This will occur at least two weeks prior to construction activities by letter box drop. Contact details for complaints and information will be provided.

• In the unlikely event that a noise or vibration complaint is received, it would be addressed within 24 hours.

• Complaints and response to complaints will be documented and documents kept for future reference.

Road traffic noise • Where practicable, ensure traffic movements, especially heavy vehicles, are limited to specified construction hours

• Avoid the use of engine compression brakes where practicable

• Advocate appropriate driver behaviour

• Ensure the road surface is maintained to assist with minimising banging/bumping noise from vehicles as they travel to and from the site, particularly when they are unloaded

• Keep truck drivers informed of designated vehicle routes, parking locations and delivery hours

Table 6-33 Additional management measures for construction activities out of standard hours.

Action required Details

Respite Period 1 • Out of hours construction noise in out of hours period 1 (evening period) shall be limited to no more than three consecutive evenings per week, except where there is a Duration Respite.

• For night work these periods of work should be separated by not less than one week and no more than 6 evenings per month

Respite Period 2 • Night time construction noise in out of hours period 2 (night period) shall be limited to two consecutive nights, except for where there is a Duration Respite.

• For night work these periods of work should be separated by not less than one week and 6 nights per month. Where possible, high noise generating works shall be completed before 11 pm.

Duration respite • Respite offers and respite periods 1 and 2 may be counterproductive in reducing the impact on the community for longer duration projects. In this instance and where it can be strongly justified it may be beneficial to increase the work duration, number of evenings or nights worked through Duration Respite so that the project can be completed more quickly.

For more information and other mitigation methods, see the ICNG (DECC - 2009) (Tables 4 – 10) and “Assessing Vibration: a technical guideline” (DEC - 2006)


6.12 Visual amenity


The proposal would take place at Burrendong Dam which is a large water storage that is maintained and operated by WaterNSW. The surrounding area is rural in nature and is used for agricultural activities as well as recreation by visitors and the local community. The dam is a prominent visual feature in the locality and is visible from surrounding areas including caravan parks and camping areas. The nearest sensitive receivers are listed in listed in Table 6-34.

Table 6-34 Sensitive receivers

ID Name Category Approximate Distance from site (m)

R1 WaterNSW workshop Industrial 700

R2 WaterNSW office Commercial 900

R3 Ridgecrest Christian Education & Convention Centre

Passive recreation area

1200

R4 Ridgecrest Education Educational institute 1900

R5 Reflections Holiday Park Passive recreation area

1900

R6 Lake Burrendong State Park Passive recreation area

2000

R7 Burrendong Botanic Garden and Arboretum

Passive recreation area

3000

R8 Lake Burrendong Sport and Recreation Centre

Active recreation area 4000


Construction

Temporary impacts to visual amenity would occur during construction in the immediate vicinity of the works. These impacts would be due to the presence of construction vehicles and equipment at the works site. Visual impacts are not considered to be significant due to the temporary nature of the works and because construction would be viewed in the context of existing water supply infrastructure.

Operation

The temporary pontoon, pump station and pipe work would be visible throughout the operational period until they are decommissioned following substantial inflows to the storage. This would be a temporary visual impact which is likely to be of low significance given the small scale of the pontoon and pipeline and the diminished water related recreation currently being engaged resulting from the drought.


Although the coffer dam would remain a permanent structure the visual impact is considered insignificant it will only be visible while the storage is below about 1% capacity. The coffer dam would be submerged at storage levels above 1% and would not be visible. During times when the coffer dam is visible, it would be viewed in the context of the existing water supply infrastructure including the adjacent to the Burrendong Dam wall and outlet tower. The coffer dam will be small in scale and will not present an obtrusive visual element.


Mitigation measures for potential visual amenity impacts are provided in Table 6-35

Table 6-35 Visual amenity mitigation measures

Visual mitigation measures


Visual impacts Work areas are to be kept clean and tidy at all times


Area to be returned to pre-construction condition at the end of the construction period

Contractor Completion of works

Any property or infrastructure damaged during works shall be repaired or replaced in consultation with WaterNSW

Contractor Completion of works

6.13 Waste, contamination and resource minimisation


A search of the NSW EPA Contaminated sites register was conducted on 30 of August 2019. No sites were recorded on, adjacent or in the vicinity of the proposal site.

The environment surrounding the site is a rural area being historically used for agricultural and water storage purposes. Currently land uses include agriculture and recreation with the dam creating/drawing tourist activities. The site is within and adjacent to water storage structures operated by WaterNSW and there are no activities undertaken at these locations that suggest there is an obvious risk of contamination.


Construction

Waste produced during construction would be managed in accordance with the waste management hierarchy. This provides that waste avoidance is a priority, followed by reuse and recycling/reprocessing, with disposal as a last resort.

Small quantities of waste (packaging, material off cuts, consumables etc) will be generated during construction. The majority of construction activities will use pre-fabricated elements that are delivered to site which reduces the likelihood of substantial volumes of waste being generated. Vehicles and machinery will be serviced off-site, other than minor repairs following breakdown.


Significant volumes of liquid wastes, including oils or fuels are unlikely to be generated during construction. Liquid and non-liquid waste would be assessed for reuse potential in accordance with the EPA’s general resource recovery exemptions before considered for disposal. If no reuse potential exists, the waste would be classified and managed in accordance with the Waste Classification Guidelines (EPA, 2014).

Domestic waste generated by construction personnel will be collected in separate waste bins for collection by a licenced contractor.

Material used to construct the coffer dam will be sourced from an area adjacent to the proposal site and used only for the construction of the dam wall. None of the material will not be disposed off-site.

The proposal is unlikely to involve activities that pollute land or lead to environmental concerns associated with storing, transporting or handling waste. All waste will be classified and disposed of in accordance with the Waste Classification Guidelines (EPA, 2014).

Operation

The proposal will result in minimal waste during operation. Waste to be generated would be associated with maintenance activities.

Decommissioning

The proposal will be decommissioned when there are inflows to Burrendong Dam that overtop the coffer dam and enable water to be discharged via the existing outlet tower. This is expected to equate to storage levels that exceed about 1% of capacity. Decommissioning will remove the aeration system along with the pontoons, pumps and pipelines. The coffer dam infrastructure along with the concrete pads required for the pipeline junctions and the compressor building of the aeration system may remain in place. Any infrastructure that is unable to be reused will be classified and managed in accordance with the Waste Classification Guidelines (EPA, 2014).


Mitigation measures for potential waste impacts are provided in Table 6-36.

Table 6-36 Waste, contamination and resource management mitigation measures

Waste, contamination and resource management mitigation measures


All waste generated by the proposal would be classified and disposed of in accordance with the NSW Waste Classification Guidelines (EPA 2014).


Resource management hierarchy principles are to be followed:

• Avoid unnecessary resource consumption as a priority

• Avoidance is followed by resource recovery (including reuse of materials, reprocessing, and recycling and energy recovery)

• Disposal is undertaken as a last resort.



Waste, contamination and resource management mitigation measures

All waste material will be removed from site once the works have been completed.


Working areas are to be maintained, kept free of rubbish and cleaned up at the end of each working day.


Self-contained portable ablution and toilet facilities shall be provided, unless negotiated otherwise with WaterNSW. These facilities shall be located at least 20 m from any natural or built drainage line or wetland. The portaloo will be pumped out and disposed offsite by a licenced provider.


If any previously unidentified contamination (e.g. sheets of asbestos, discoloured soil, strong chemical or petrol odours, refuse or leachate) is discovered during works, works would halt and WaterNSW would be notified immediately to determine appropriate response measures.


6.14 Cumulative impacts

Cumulative environmental impacts include the combined effect of individual impacts associated with the proposal, in addition to the impacts of other activities in the locality. The Burrendong Dam locality is rural in character. WaterNSW infrastructure is operated and maintained in the areas surrounding the site. The proposal is unlikely to result in a cumulative impact due to other activities in the locality.

As indicated in section 2.2.2, a range of actions have been and will continue to be implemented to provide water for critical human need in the Macquarie Valley in accordance with a Stage 4 critical drought/water shortage as defined in the Macquarie-Castlereagh IRG. This includes:

Stage 1 – Raising the operating level of the Warren Weir and blocking flow through fishways at the Warren Weir and Duck, Crooked Creek, Gunningbar Creek and Marebone Regulators.

Stage 2 - Bulk transfers from Windamere Dam storage to increase the storage in Burrendong Dam.

Stage 3 - Pumping from Burrendong Dam deep storage to access 21 GL of water that cannot be accessed under normal operating conditions. This water would be discharged to the Macquarie River downstream of the Burrendong Dam to supply cities and towns including Dubbo, Wellington, Nyngan, Cobar and Warren.

Temporary changes to water delivery arrangements, including:

– Reduced or suspended licence allocations. – Suspension of the operation of the Water Sharing Plan for the Macquarie and

Cudgegong Regulated Rivers Water Source 2016 with respect to planned environmental releases, available water determinations and water allocation account management in relation to the Macquarie Regulated River due to an extreme dry period. The concurrence of the Commonwealth Minister for Energy and Environment was obtained before making this order.

– Using ground water source as an alternative supply source. Towns such as Dubbo currently use groundwater sources as a supplement to water supply from Burrendong


Dam. Additional bores are to be installed to access groundwater to further supplement surface water supplies.

As indicated in section 2.2.2, the cumulative impact of the proposal, in addition to Stages 1 and 2 is predicted to conserve surface water supplies in Burrendong Dam to delay a cease to flow event in ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren by about seven months. This is likely to lead to significant positive socio-economic and environmental outcomes compared to the do-nothing scenario.

The proposal will contribute to the water management works for drought security by increasing the duration that the Macquarie River is able to be operated to supply water to the towns and cities downstream of Burrendong Dam. This is consistent with the NSW government’s requirement that water be prioritised for critical human water needs.


7. Environmental management 7.1 Construction environmental management plan

The proposal will be delivered in accordance with a comprehensive suite of environmental mitigation measures and controls that are designed to mitigate the potential environmental impacts. These measures will be documented in a CEMP and applied during construction and operation of the proposal.

The CEMP will describe safeguards and management measures identified in section 6 of this REF and any additional measures required by licences, permits or approvals that are required to construct the proposal. This will provide a framework for establishing how measures will be implemented and who will be responsible for their implementation.

The CEMP will be prepared prior to commencement of construction and be reviewed and endorsed by WaterNSW. The CEMP will be a working document, subject to ongoing change and updated as necessary.

The key objective of the CEMP will be to ensure that environmental commitments made in the REF, and conditions imposed by any licences and approvals, are implemented throughout the construction period. The CEMP will include the following information:

Details of all positions and contact details of all key personnel

Audit and reporting program to ensure all actions/measures are implemented.

Training requirements, including site induction requirements to ensure that all personnel understand the principles of environmental management.

Emergency and incident response procedures.

List of approvals to be obtained before work commences.

Consultation requirements (government and community) and complaint handling procedures.

Actions for meeting environmental objectives based on the mitigation measures identified in this REF and any statutory or regulatory obligations.

Details of person responsible for the implementation of each action.

7.2 Operational environmental management

The proposal will be operated by WaterNSW in accordance with procedures that apply to the remainder of its water supply network, including arrangements to implement temporary works during droughts. Specific measures that will be developed in consultation with relevant government agencies and implemented relate to:

Adaptive management of the Macquarie River system with prioritisation of supply as outlined in section 2.1.2.

Water quality monitoring plan as indicated in sections 3.4.2.


8. Conclusion 8.1 Justification of the proposal

The current drought is having a severe impact on water storages in the Macquarie River catchment, including Burrendong Dam which is the main storage within the system. Inflows to Burrendong Dam between May 2017 – April 2019 were 38 % of the previous drought of record and the dam has fallen to 4% of its total capacity by 1 October 2019. The Macquarie River is projected to cease to flow downstream of Burrendong Dam in March 2020 if there are no inflows to the system.

The Macquarie River supplies water to cities and towns that include Dubbo, Wellington, Narromine, Warren, Nyngan and Cobar. High security water users in the Macquarie Valley which include major urban centres, permanent plantings, stock and domestic water supply schemes, industry, and other uses such as the Western Plains Zoo at Dubbo.

WaterNSW, local water utilities (Councils) and DPIE-W, are jointly and individually planning to implement projects and actions in stages to conserve water and provide emergency water supplies to affected communities. This includes implementing temporary works to supply water to towns, communities and high security water users downstream of Burrendong Dam.

The proposed works to access the 21 GL of inactive deep water storage in the Burrendong Dam is Stage 3 to a three stage plan to extend water availability and delay a cease to flow event in the Macquarie River below Burrendong Dam. The combined effect of these three stages is predicted to extend water supply for critical human water needs and delay a cease to flow event in the Macquarie River downstream of Burrendong Dam by about seven months.

The proposal is justified because it would prioritise water for critical human water needs. The Minister for Water has issued an order to suspend part of the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 with respect to planned environmental releases, available water determinations and water allocation account management due to the extreme dry period. This reflects a NSW Government decision, with concurrence from the NSW Minister for Energy and Environment, that environmental releases are to cease and water is to be prioritised for critical human water need. This prioritisation of water for critical human water need is consistent with the intent of the Macquarie-Cudgegong IRG and would provide significant benefits to cities and towns downstream of Burrendong Dam including Wellington, Dubbo, Narromine, Warren, Nyngan and Cobar.

The proposal is also justified because it would extend river flows in the ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren. This will extend the duration that aquatic fauna are able to move between refuge habitat within the river and reduce the risk of adverse water quality conditions developing within the river. This is a beneficial impact compared to the do-nothing scenario which is predicted to result in a cease to flow event that would affect the whole ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren in March 2020 if there are no inflows to Burrendong Dam.

The proposal is designed to:

Be cost effective by maximising the use of existing infrastructure and minimising the need to invest in new infrastructure

Enable it to be constructed and commissioned within a short timeframe in response to the current drought


Enable it to be decommissioned within a short timeframe in advance of inflows to Burrendong Dam

Minimise environmental impacts by limiting construction to existing disturbed areas.

Section 8.2 demonstrates that the proposal is consistent with the principles of ESD.

The proposal will be constructed and operated in accordance with any requirements issued under the Fisheries Management Act 1994. Operational impacts would be monitored by implementing water quality and aquatic ecology monitoring plans that would be developed in consultation with DPIE-W, and DPIE and the DPIF.

8.2 Principles of ecological sustainable development

8.2.1 The precautionary principle

The precautionary principle states that:

‘if there are threats of serious or irreversible environmental damage, lack of full scientific certainty should not be used as a reason for postponing measures to prevent environmental degradation’

Environmental assessments have been undertaken to prepare this REF to ensure that the potential environmental impacts can be understood with a high degree of certainty.

The proposal is required to maintain water supply for critical human water needs in the Macquarie River downstream of Burrendong Dam. It will occur in a highly regulated river system and civil works will be limited to areas that have been previously disturbed by construction and operation of water supply infrastructure. Potential environmental impacts have been assessed and mitigation measures and safeguards are proposed to protect the environment.

The proposal has evolved to avoid environmental impact where practicable and mitigation measures can be implemented to minimise impacts. No mitigation measures have been deferred due to a lack of scientific certainty. A mitigation program would be implemented to monitor water quality and the response of the aquatic environment within and downstream of Burrendong Dam. This would enable the direct impacts of the proposal to be monitored and allow the mitigation measures to be implemented according to the observed environmental responses. The proposal is therefore considered to be consistent with the precautionary principle.

8.2.2 Inter‑generational equity

The principle of inter-generational equity states that:

‘the present generation should ensure that the health, diversity and productivity of the environment are maintained or enhanced for the benefit of future generations’

Compared to the do-nothing scenario, the proposal is unlikely to impact on natural or cultural features to a level that will compromise the health, diversity or productivity of the environment to a level that will impact on future generations.

The proposal is temporary and will be decommissioned when substantial flows in the system recommence.

The proposal would benefit the present and future generations as it will supply water for critical human needs in the Macquarie River downstream of Burrendong Dam.


8.2.3 Conservation of biological diversity and ecological integrity

The principle of biological diversity and ecological integrity states that:

‘conservation of biological diversity and ecological integrity should be a fundamental consideration’

The proposal will have no direct impact on vegetation as no vegetation is to be removed for the construction or operation of the proposal.

The Macquarie River is a highly regulated system and waterways have been impacted by and responded to, changes to flow regimes due to river regulation that have reduced the frequency of cease to flow events. Due to current drought conditions and implementation of the Macquarie Drought Response project Stage 1 measures, the Macquarie River ceased to flow downstream of the Warren in September 2019. The Macquarie River is predicted to cease to flow between Burrendong Dam and Warren in March 2020 if the proposal is not implemented and there are no inflows to Burrendong Dam. This would result in a cease to flow event along the full length of the Macquarie River downstream of Burrendong Dam.

The proposal will have adverse biodiversity impact as water quantity and quality may be reduced in Burrendong Dam. This will reduce the habitat availability for the fish community in Burrendong Dam, however, compared to the do-nothing scenario, the habitat quality in the deep water storage will be improved because:

The aeration system will maintain DO levels above 1.58 mg/L which is the lethal threshold for Murray Cod. The lethal threshold for other threatened native fish species likely to be present in the reservoir are lower than the threshold for Murray Cod.

Exotic European Carp may be removed from Burrendong Dam to reduce biomass and competition with native species once the reservoir level drops due to pumping

Any dead fish will be quickly removed from the deep water storage to minimise the potential impact on organic carbon and nutrient concentrations.

The proposal will have positive impacts by delaying a cease to flow event in the ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren. This will:

Extend the duration that aquatic habitat is maintained in this section of the river, and the duration that fish are able to move between refuge habitat within the river compared to the do-nothing scenario.

Reduce the risk of adverse water quality conditions developing within this section of the river compared to the do-nothing scenario.

The beneficial biological impacts of deferring a cease to flow event in the main channel of the Macquarie River are considered to outweigh the adverse impacts that will occur from retaining the deep storage within Burrendong Dam.

A mitigation program is to be implemented to monitor water quality and the response of the aquatic environment within and downstream of Burrendong Dam. This would enable the direct impacts of the proposal to be monitored and allow for the mitigation measures to be implemented according to the observed environmental responses.

8.2.4 Appropriate valuation of environmental factors

The principle of improved valuation of environmental resources states that:

‘environmental factors should be included in the valuation of assets and services’

This principle relates to giving monetary values to environmental resources. The cost of environmental resources includes costs incurred to protect the environment. The safeguards


imposed to minimise adverse impacts would result in economic costs to WaterNSW. The proposal has been designed to minimise adverse environmental impacts on the environment by implementing appropriate mitigation measures where impacts are likely.

The proposal would assist to ensure that water is delivered is a safe and sustainable way for critical human need. These factors ensure that the development would conform to the principles of “ecologically sustainable development”.

8.3 Conclusion

The REF assesses the potential impacts of the proposal. It has been prepared in accordance with Part 5 of the EP&A Act and considers the factors listed in clause 228 of the Regulation (refer Appendix C). The REF documents the potential environmental impacts of the proposal, considering both potential positive and negative impacts and recommends management and mitigation measures to protect the environment where required. The mitigation measures allow be adaptive responses based on monitoring outcomes.

There will be short term, temporary, minor adverse impacts during construction. The main issues would be associated with impacts on:

Soil and water due to erosion and sedimentation

Air quality due to dust from exposed surfaces

Noise due to the operation of machinery and equipment

Traffic and access

Operational impacts will be temporary as the proposal will be decommissioned following substantial inflows to Burrendong Dam allowing normal operations and the drought declaration being lifted by the Minister.

The main impacts associated with operation of the proposal would include:

Noise from the operation of the temporary pump station

Biodiversity due to the reduction of water quantity within the reservoir.

The proposal will provide a significant benefit to the community as it would prioritise water for critical human water needs to towns and communities along the Macquarie River downstream of Burrendong Dam.

Overall, potential negative impacts associated with the proposal can be adequately managed by implementing the mitigation measures in section 6, and the beneficial impacts are considered to outweigh the adverse impacts. Compared to the do-nothing scenario, the proposal is unlikely to have a significant impact on the environment and does not require an EIS to be prepared, or a referral to the Commonwealth under the EPBC Act.

If the proposal assessed in this REF changes, WaterNSW would determine whether additional environmental assessment is needed to ensure that their obligations under the EP&A Act are addressed.


9. References BCD (2019a) BioNet Atlas species sighting search. Accessed from https://www.environment.nsw.gov.au/atlaspublicapp/UI_Modules/ATLAS_/AtlasSearch.aspx. Accessed on 09 September 2019.

BCD (2019b) BioNet threatened species profile search. Accessed from https://www.environment.nsw.gov.au/threatenedspeciesapp/ on 09 September 2019.

BCD (2019c). BioNet Vegetation Classification. Accessed from https://www.environment.nsw.gov.au/research/Visclassification.htm.

DECC 2009, Interim Construction Noise Guideline (ICNG), Department of Environment and Climate Change NSW.

DECCW 2011, NSW Road Noise Policy, Department of Environment, Climate Change and WaterNSW.

DoEE (2019a) Protected Matters Search Tool. Accessed from http://www.environment.gov.au/epbc/pmst/ on 09 September 2019.

DoEE (2019b) Online species profiles and threats database. Accessed from http://www.environment.gov.au/cgi-bin/sprat/public/sprat.pl on 30 August 2019.

DPI (2015) Short-term intervention monitoring of a fish community response to an environmental flow in the mid and lower Macquarie River: 2014/2015 watering year, Commonwealth of Australia 2015.

DPI (2019b). NSW Weedwise Priority Weeds Database, Department of Primary Industries. http://weeds.dpi.nsw.gov.au/

DPIE (2015). State Vegetation Type Map- Central West Lachlan –VIS_ID 4682. NSW Government.

EPA 2017, Noise Policy for Industry (NPI), Environment Protection Authority

HydroScience Consulting (2011). Central Tablelands Water Drought Management Plan. Central Tablelands Water

HydroScience Consulting (2015). Dubbo City Council Drought Management Plan. Dubbo City Council.

MDBC (2008). Murray–Darling Basin Rivers: Ecosystem Health Check, 2004–2007. A summary report based on the Independent Sustainable Rivers Audit Group’s SRA Report 1: A Report on the Ecological Health of Rivers in the Murray–Darling Basin, 2004–2007, Murray–Darling Basin Authority.

MDBC (2012). Sustainable Rivers Audit 2: The ecological health of rivers in the Murray–Darling Basin at the end of the Millennium Drought (2008–2010). Summary. Murray–Darling Basin Authority.

NSW Government (2019). Sharing and Enabling Environmental Data (SEED) Portal. Accessed from https://www.seed.nsw.gov.au/.

NSW Heritage Office (2005), The State Agency Heritage Guide: Management of Heritage Assets by NSW Government Agencies.

OzArk Environment and Heritage (OzArk) (2019).Desktop Aboriginal Due Dilligence Assessment and Statement of Heritage Impact Report.

https://www.environment.nsw.gov.au/research/Visclassification.htm


TfNSW 2018, Construction Noise and Vibration Strategy, Transport for NSW.

WaterNSW (2019). Real Time Data- Burrendong Dam. Accessed from https://realtimedata.waternsw.com.au/ on 23 September 2019.

https://realtimedata.waternsw.com.au/

GHD | Report for WaterNSW - Burrendong Dam Deep Water Storage Access, 12512398

Appendices


Appendix A – Water sharing plan suspension order

Government Gazetteof the State of

New South Wales

2481 NSW Government Gazette No 69 of 4 July 2019

Number 69Thursday, 4 July 2019

GOVERNMENT GAZETTE – 4 July 2019

The New South Wales Government Gazette is the permanent public record of official NSW Government notices. It also contains local council, private and other notices.

From 1 January 2019, each notice in the Government Gazette has a unique identifier that appears in round brackets at the end of the notice and that can be used as a reference for that notice (for example, (n2019-14)).

The Gazette is compiled by the Parliamentary Counsel’s Office and published on the NSW legislation website (www.legislation.nsw.gov.au) under the authority of the NSW Government. The website contains a permanent archive of past Gazettes.

To submit a notice for gazettal – see Gazette Information.

By AuthorityGovernment PrinterISSN 2201-7534

Government Notices


GOVERNMENT NOTICESWater Notices

Water Sharing Plan Part Suspension (Belubula Regulated River) Order 2019

under the

Water Management Act 2000

I, Melinda Pavey, Minister for Water, Property and Housing, in pursuance of section 49B of the

Water Management Act 2000, and being satisfied that there is an extreme event in relation to the

Belubula Regulated River Water Source, make the following Order.

Dated 3 July 2019

Melinda Pavey

Minister for Water, Property and Housing

Explanatory note This Order suspends part of the operation of the Water Sharing Plan for the Belubula Regulated River Water Source 2012 with respect to end of system flow requirements due to an extreme dry period.

The Order is made under section 49B of the Water Management Act 2000. The concurrence of the

Minister for Energy and Environment was obtained before the making of this Order. This Order

expires on 30 June 2020 unless sooner revoked.

Government Notices


Water Sharing Plan Part Suspension (Belubula Regulated River) Order 2019

under the


1 Name of Order

This Order is the Water Sharing Plan Part Suspension (Belubula Regulated River) Order 2019.

2 Commencement

This Order commences the day on which it is published in the Gazette.

Note. This order expires at the end of 30 June 2020 unless sooner revoked in accordance with section 49B (4) of the Water Management Act 2000.

4 Suspension

The operation of clause 26 of the Water Sharing Plan for the Belubula Regulated River Water Source 2012 is suspended.

(n2019-1895)

Government Notices



under the


I, Melinda Pavey, Minister for Water, Property and Housing, in pursuance of section 49B of the

Water Management Act 2000, and being satisfied that there is an extreme event in relation to the

Macquarie Regulated River, make the following Order.

Dated 3 July 2019

Melinda Pavey

Minister for Water, Property and Housing

Explanatory note This Order suspends part of the operation of the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 with respect to planned environmental releases,

available water determinations and water allocation account management in relation to the Macquarie

Regulated River due to an extreme dry period. The Order is made under section 49B of the Water Management Act 2000. The concurrence of the Minister for Energy and Environment was obtained

before the making of this Order. This Order expires on 30 June 2020 unless sooner revoked.

Government Notices



under the


1 Name of Order

This Order is the Water Sharing Plan Part Suspension (Macquarie Regulated River) Order 2019.

2 Commencement

This Order commences on 1 July 2019. Note. This order expires at the end of 30 June 2020 unless sooner revoked in accordance with section 49B (4) of the Water Management Act 2000.

3 Interpretation

(1) In this order:

Macquarie Regulated River means the regulated rivers declared in the Central West Water Management Area Regulated River Order (Government Gazette No 110 of 1 July 2004) as

amended by the Water Management Act 2000 except for the following:

(a) Cudgegong River from Windamere Dam wall, being the point at latitude - 32.727325

and longitude 149.771999 in decimal degrees GDA94, downstream to Burrendong Dam

water storage,

(b) Mebul Creek, from its junction with the Cudgegong River to a point 25 metres upstream,

(c) Ruins Creek, from its junction with the Cudgegong River to a point 20 metres upstream,

(d) Windamere Dam water storage (including all the water downstream as described by the

order to Windamere Dam wall).

(2) Unless otherwise defined, words and expressions that are defined in the Water Management Act 2000 or in regulations made under that Act have the same meaning in this Order.

4 Suspension

The operation of the following provisions of the Water Sharing Plan for the Macquarie and Cudgegong Regulated Rivers Water Source 2016 are suspended to the extent to which the

provisions apply to the Macquarie Regulated River downstream of the Burrendong Dam

water storage:

(a) subclauses 14 (10), (11), (12), (13), (14), (15), (16), (17), (18), (19), (20), (21) and

(22),

(b) clauses 33, 34, 35, 36, 37 and 38,

(c) clause 44 (3) (a).

(n2019-1896)


Appendix B – WaterNSW Community Media Release – June 2019 Operations Update

Operations update

Water Delivery Arrangements

Macquarie River

WaterNSW ABN 21 147 934 787

169 Macquarie Street Parramatta NSW 2150

PO Box 398, Parramatta NSW 2124

T 1300 662 077 E [email protected] waternsw.com.au

1 July 2019

Update

The severe and ongoing drought conditions across NSW are having a significant impact on the

ability of WaterNSW to deliver water to customers.

Over the last two years, rainfall across northern NSW has been well below average and in many

areas are now the lowest ever recorded. This, combined with higher than average temperatures,

has resulted in record low inflows to the storages. Inflows to Burrendong Dam are 36% of the

previous low record.

While allocations for the Macquarie River system have been announced by the NSW Department

of Planning, Industry and Environment, the delivery of water is restricted due to the ongoing

drought.

The Macquarie River system is currently being operated under drought contingency measures with

water delivery restrictions.

The water delivery restrictions and operational arrangements are outlined in the tables below and

are specifically outlined for each river section to best assist landholders and customers with

information relevant to their specific circumstances

Access to water this year will be highly dependent on further inflows into the catchment and

associated tributary inflows downstream from WaterNSW storages.

We encourage our customers and community to stay up to date with the latest information via the

options below.

Stay informed

1. Early Warning Network (EWN)

Customers will be notified of access arrangements through our EWN. If you have not

already signed up to the system, please phone us on 1300 662 077 or email us at

[email protected]





2. eNewsletters

Customers can stay up to date through weekly email communications sent by WaterNSW.

Visit waternsw.com.au/subscribe to choose which reports you would like to receive.

3. Website

Drought information is available on our website and updated weekly. Visit

waternsw.com.au/supply/drought-information

AWDs for Macquarie River 1 July 2019

Licence Category AWD Deliverability

Domestic and Stock 80% Restricted – please see details below

Domestic and Stock (Domestic) 80% Restricted – please see details below

Domestic and Stock (Stock) 80% Restricted – please see details below

Local Water Utility 80%

Regulated River (General Security) 0% Restricted – please see details below

Regulated River (General Security)

Carryover allocations

n/a Restricted – please see details below

Regulated River (High Security) 70% Restricted – please see details below

Regulated River (High Security) (Research) 35% Restricted – please see details below

Regulated River (High Security)

(Town Water Supply)

35% Restricted – please see details below

Supplementary Water 100% Subject to availability

Deliverability of ordered water

River section Licence category Type of restriction Period of

applicability

Method of placing water

order

Burrendong

Dam to

Warren Weir

All licence

categories

Unrestricted delivery of

account water. Water orders

to be placed as normal.

Until further

notice iWAS and customer help

desk.

Burrendong

Dam to

Warren Town

Weir (ESID:

2159)

Local Water Utility Unrestricted delivery of



Until further


desk.

Warren Weir

to Marebone

Weir

All licence

categories

Delivery of account water

only with tributary flows and

not with dam releases.

Until further

notice

Only via customer help

desk.





Water order is required to be

placed and need to be

approved by WaterNSW.

Confirmation of water

order from WaterNSW is

required.

Downstream

of Marebone

Weir

All licence

categories







Until further

notice


desk.



required.

Downstream

of Marebone

Break and

Bulgeragar

Creek

All licence

categories







Until further

notice


desk.



required.

Gunningbar

Creek offtake

to

Gunningbar

Weir

All licence

categories




Until further


desk.

Gunningbar

Weir to

Bogan River

confluence

All licence

categories




Until further


desk.

Downstream

of Duck

Creek offtake

All licence

categories







Until further

notice


desk.



required.

Downstream

of Crooked

Creek offtake

All licence

categories







Until further

notice


desk.



required.

Trade restrictions

River section Licence category Type of restriction Period of applicability

Macquarie River General Security Trading from general security licences

in the Macquarie River to any licences

in Macquarie or Cudgegong rivers is

suspended

Until further notice

Macquarie River High security and

Supplementary

licences

Trading is unaffected Until further notice





Cudgegong River

to Macquarie River

All licence

categories

Trading of allocations is suspended Until further notice

Macquarie River to

Cudgegong River

High security and

Supplementary

licences

Trading is unaffected Until further notice

Authorised by

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Water System Operations Manager Central

More information

Please visit our website for more information at waternsw.com.au/supply/regional-nsw/customer-

notices. For more information on this event, phone us on 1300 662 077 or email us at

[email protected].


Appendix C – Clause 228 review Clause 228 Factor Impacts (a) Any environmental impact on a community? The proposal would have minor, short term impacts on the community due to amenity-based impacts during construction relating to noise, traffic, access and visual amenity. These impacts will be very localised and the mitigation measures in Section 6 of the REF will be implemented to minimise impacts.

Minor adverse

(b) Any transformation of a locality? The proposal would not transform a locality because the works would be temporary and would be removed once the drought declaration is lifted. The temporary works would be viewed in the context of the existing water supply infrastructure blending with the local amenity.

Minor adverse

(c) Any environmental impact on the ecosystem of the locality? Section 6.3.2 of the REF indicates that the proposal would result in both positive and adverse hydrological impacts within this highly regulated catchment, and this is likely to have associated positive and adverse ecological impacts as discussed in Section 6.4.2. Potential impacts of this event would include declining water quality and quantity, and associated consequences such as fish kills. However the proposal would have a beneficial impact as water flows would still be available downstream of the Burrendong Dam. Under the do-nothing scenario, about ~391 kilometres of the Macquarie River would be affected by a cease to flow event in March 2020. The proposal would have a beneficial impact as it would maintain flows to the Macquarie River, and therefore maintain ecosystem health to aquatic and riparian habitat that is to be affected by a cease to flow event. This would extend the duration that refuge habitat is provided within the Macquarie River and reduce the risk of adverse water quality conditions developing. This is a beneficial impact compared to the do-nothing scenario.

Moderate negative impact to water quality in the Burrendong Dam by reducing water quantity Positive impact by preventing a cease to flow event in the case of the do-nothing scenario.

(d) Any reduction of the aesthetic, recreational, scientific or other environmental quality or value of a locality? The proposal would have a short term impact on the aesthetic and recreational value of the locality because construction is adjacent to a public reserve. This impact would be temporary because construction and operation of the proposal is temporary and would be decommissioned once the drought declaration is lifted.

Minor

(e) Any effect on a locality, place or building having aesthetic, anthropological, archaeological, architectural, cultural, historical, scientific or social significance or other special value for present or future generations? The proposal would not impact on any places of heritage significance.

Nil

(f) Any impact on the habitat of protected fauna (within the meaning of the National Parks and Wildlife Act 1974)? The proposal would result in reduced water volume of the Burrendong Dam. This has the potential to result in reduce the quality of water in the dam and may lead to fish kills. Potential impacts on protected terrestrial and aquatic fauna within the Dam would be less to that which is predicted to occur under the do-nothing scenario which would result in the Macquarie River ceasing to flow between Burrendong Dam and the Macquarie Marshes in March 2019. The proposal would have a positive impact on protected terrestrial and aquatic fauna by delaying a cease to flow event in the ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren which provide riparian habitat for a range of species. The mitigation measures outlined in Section 6 would be implemented to minimise the risk of adverse impacts.

Positive impact downstream of Burrendong Dam through to Warren. Minor impacts to Burrendong Dams water quality compared to the do-nothing scenario


Clause 228 Factor Impacts (g) Any endangering of any species of animal, plant or other form of life, whether living on land, in water or in the air? The proposal would have a positive impact compared to the do-nothing scenario by delaying a cease to flow event in Macquarie River. The proposal will positively impact on protected terrestrial and aquatic fauna by delaying a cease to flow event in the ~314 kilometre long section of the Macquarie River between Burrendong Dam and Warren which provide riparian habitat for a range of species. The mitigation measures outlined in section 6 would be implemented to minimise the risk of adverse impacts.

Positive impact on the Macquarie River between Burrendong Dam and Warren

(h) Any long-term effects on the environment? The proposal is unlikely to have long-term effects on the environment as it would be temporary and would be decommissioned once the drought declaration is lifted. The ecosystem of the dam would recover over time once the drought is broken and water levels rise.

Minor

(i) Any degradation of the quality of the environment? The proposal has the potential to result in poor water quality developing in Burrendong Dam deep water storage. Water quality would be monitored and mitigation measures would be implemented to reduce the risk of declining water quality resulting in impacts such as fish kills. This risk is considered minor compared to the do-nothing scenario resulting in a cease to flow event downstream of the Macquarie River.

Minor

(j) Any risk to the safety of the environment? The proposal is unlikely to result in risks to the safety of the environment provided the recommended mitigation measures are implemented. The proposal is temporary and construction would be limited to localised areas.

Minor

(k) Any reduction in the range of beneficial uses of the environment? The proposal is unlikely to have any reduction in the range of beneficial uses of the environment compared to the do-nothing scenario. The proposal is temporary and would be decommissioned once the drought declaration is lifted. Construction would be short term and limited to existing disturbed sites of WaterNSW water supply infrastructure.

Nil

(l) Any pollution of the environment? The proposal is unlikely to cause any pollution of the environment provided the recommended mitigation measures are implemented.

Nil

(m) Any environmental problems associated with the disposal of waste? The proposal is unlikely to cause any environmental problems associated with the disposal of waste. All waste would be managed and disposed of in accordance with the Waste Classification Guideline (EPA, 2014).

Minor

(n) Any increased demands on resources (natural or otherwise) that are, or are likely to become, in short supply? The proposal is a temporary measure that would prioritise water for critical human water needs and would be decommissioned once the drought declaration is lifted. The proposal would not impact on any other resources that are likely to be or become in short supply.

Positive impact downstream of Burrendong Dam relative to the do-nothing scenario

(o) Any cumulative environmental effect with other existing or likely future activities? The proposal would have positive impacts as it would be the third of a three stage schedule of temporary works that would be implemented to delay a cease to flow event in the ~314 kilometre long section of the Macquarie River between Burrrendong Dam and Warren. Delaying the cease to flow event reduces the risk that WaterNSW is unable to operate the river to deliver water to meet critical human water needs.

Positive impact upstream of Warren

(p) Any impact on coastal processes and coastal hazards, including those under projected climate change conditions? The proposal would not affect or be affected by any coastal processes or hazards.

Nil


Appendix D – Water Quality and Aquatic Ecology Impact Assessment

WaterNSW Burrendong Deep Water Storage Access

Water quality and Aquatic Ecology Impact Assessment

November 2019

GHD | Report for WaterNSW - Burrendong Deep Water Storage Access, 12512398 | i

Executive summary The Macquarie River system is presently classified as being in a Stage 4 drought – critical drought / water shortage and is being operated under drought contingency measures with water delivery restrictions. WaterNSW is completing works in the catchment in a staged approach, and proposes to access the deep water storage at Burrendong Dam. Current water storage levels of the Burrendong Dam are at critical levels being measured at 4.4% (18 September 2019). Once at 0% the dam has approximately 21.5 GL of deep-water storage that is below the level that is able to be accessed using the existing outlet infrastructure. Of this, approximately 15.5 GL is proposed be used to maintain flows in the Macquarie River downstream of the dam, leaving 6 GL which would be managed to provide habitat for the existing fish community.

The existing conditions in Burrendong Dam and Macquarie River directly downstream of the dam indicate that water quality is generally protective of aquatic life, with no concentrations of toxicants which are likely to adversely impact aquatic species. Nutrient concentrations are elevated however, and while anoxic conditions have not yet been observed there is the potential for algal blooms to result in reduced dissolved oxygen concentrations and potentially fish kills without intervention.

Aquatic habitat observed at Burrendong Dam and Macquarie River during a site inspection on 28 August 2019 was classed as good and excellent respectively. The reaches of the Macquarie River downstream of Burrendong Dam are likely support populations of native fish species, including species protected under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) and/or the Fisheries Management Act 1994 (FM Act), such as Murray Cod, Eel Tailed Catfish, Silver Perch and Trout Cod. The proposal will have beneficial ecological impacts by maintaining flows within the section of the Macquarie River downstream of Burrendong Dam, which provides habitat for these protected species.

While the proposal will reduce habitat availability for the fish community in Burrendong Dam, it is predicted that there will be benefits to the water quality and aquatic ecology in the 6 GL which will remain in the deep storage area. The benefits are likely to occur due to the aeration system which will be installed, and the proposed mitigation measures, which include exotic biomass minimisation and the removal of any dead fish, in the case that they are observed during regular monitoring. These water quality and aquatic ecology benefits would not be observed under the do-nothing scenario.

Continued extreme drought conditions in the Macquarie River have severe potential impacts on water quality and aquatic ecology in Burrendong Dam and the downstream reaches of the river. The proposal will minimise the impacts in the downstream reaches of the river by maintaining flows, as well as manage and mitigate the potential impacts within the dam, where the proposed mitigation measures are more practical and achievable.

This report is subject to, and must be read in conjunction with, the limitations set out in Section 1.3 and the assumptions and qualifications contained throughout the Report.

GHD | Report for WaterNSW - Burrendong Deep Water Storage Access, 12512398 | ii

Table of contents 1. Introduction..................................................................................................................................... 1

1.1 Background .......................................................................................................................... 1

1.2 Purpose of this report........................................................................................................... 1

1.3 Scope and limitations ........................................................................................................... 2

2. Methodology ................................................................................................................................... 3

2.1 Sites visited .......................................................................................................................... 3

2.2 Water quality sampling......................................................................................................... 3

2.3 Habitat assessment ............................................................................................................. 3

2.4 Fish community assessment ............................................................................................... 4

2.5 Data analysis ....................................................................................................................... 4

2.6 Quality assurance ................................................................................................................ 5

3. Existing conditions ......................................................................................................................... 7

3.1 Water quality ........................................................................................................................ 7

3.2 Aquatic habitat ................................................................................................................... 15

3.3 Fish community .................................................................................................................. 18

4. Impact assessment ...................................................................................................................... 21

4.1 Water quality ...................................................................................................................... 21

4.2 Aquatic Ecology ................................................................................................................. 24

5. Management, monitoring and mitigation measures ..................................................................... 26

5.1 Monitoring .......................................................................................................................... 26

5.2 Mitigation measures ........................................................................................................... 26

6. Conclusions .................................................................................................................................. 28

7. References ................................................................................................................................... 29

Table index Table 2-1 Analytical schedule - water samples .................................................................................... 3

Table 2-2 Modified RCE total score and statuses ................................................................................ 4

Table 3-1 In situ water quality results, 28 August 2019 ....................................................................... 7

Table 3-2 Results of laboratory analysis of samples collected 28 August 2019 .................................. 8

Table 3-3 Photos and habitat observations, 28 August 2019 ............................................................ 16

Table 3-4 Results of the RCE assessment ........................................................................................ 18

Table 3-5 List of fish species likely to be present in Burrendong Dam and Macquarie River downstream of the dam. .................................................................................................... 19

Table 3-6 Water quality preferences and tolerances of native fish likely in Burrendong Dam and Macquarie River. ................................................................................................ 20

Table 5-1 Mitigation measures for potential impacts on water quality and aquatic ecology .............. 26

GHD | Report for WaterNSW - Burrendong Deep Water Storage Access, 12512398 | iii

Figure index

Figure 2-1 Sites visited on 28 August 2019 .......................................................................................... 6

Figure 3-1 Temperature profile in Burrendong Dam, 13 September 2019 ........................................... 9

Figure 3-2 DO profile in Burrendong Dam, 13 September 2019 ........................................................... 9

Figure 3-3 pH profile in Burrendong Dam, 13 September 2019 ......................................................... 10

Figure 3-4 Turbidity profile in Burrendong Dam, 13 September 2019 ................................................ 10

Figure 3-5 Major cation depth profiles in Burrendong Dam ................................................................ 11

Figure 3-6 Major anion depth profiles in Burrendong Dam ................................................................. 11

Figure 3-7 Total nitrogen depth profiles in Burrendong Dam .............................................................. 12

Figure 3-8 Total phosphorous depth profiles in Burrendong Dam ...................................................... 12

Figure 3-9 Total algae and cyanobacteria depth profiles in Burrendong Dam ................................... 12

Figure 3-10 Algal biovolume depth profiles in Burrendong Dam .......................................................... 13

Figure 3-11 Cyanobacterial biovolume depth profiles in Burrendong Dam .......................................... 13

Figure 3-12 Total algae counts in Burrendong Dam since 2015 ........................................................... 14

Figure 3-13 Total cyanobacteria counts in Burrendong Dam since 2015 ............................................. 14

Figure 3-14 Algal biovolume in Burrendong Dam since 2015 ............................................................... 14

Figure 3-15 Cyanobacterial biovolume in Burrendong Dam since 2015............................................... 15

Figure 4-1 Anticipated extent of the 20 GL deep storage and the 6 GL draw down level .................. 23

Appendices Appendix A – Certificate of analysis

Appendix B – Water quality QA

Appendix C – Assessments of Significance

GHD | Report for WaterNSW - Burrendong Deep Water Storage Access, 12512398 | 1

1. Introduction 1.1 Background

WaterNSW is Australia’s largest supplier of raw water, delivering water from 42 dams, state rivers and pipelines to NSW irrigators, licenced authorities, retail suppliers and councils. WaterNSW develops infrastructure solutions to ensure water supply security and contributes to the protection of the environment and catchments.

WaterNSW operates and maintains dams, weirs and ancillary structures across the Macquarie Valley system in western NSW to deliver water to customers. WaterNSW also works with the Department of Planning, Industry and Environment (DPIE) to assess drought conditions and determine whether it is necessary to reduce water allocations to licence holders.

The Macquarie River Catchment is regulated to mitigate flooding and supply water to cities and towns that include Dubbo, Wellington, Narromine, Warren, Nyngan and Cobar. The main water storages in the catchment are Lake Burrendong on the Macquarie River upstream of Wellington, and Lake Windamere which is on the Cudgegong River upstream of Mudgee.

The Macquarie River system is presently classified as being in a Stage 4 drought – critical drought / water shortage and is currently being operated under drought contingency measures with water delivery restrictions. Current drought conditions are having a severe effect on storages, the river system, towns, environment and irrigators. WaterNSW, local water utilities (Councils) and DPIE are jointly and individually planning to implement, are implementing or have implemented a range of projects and actions to provide emergency water supplies to affected communities under the Stage 4 drought conditions.

Works are to be completed using a staged approach. Stage 1 was completed in early September and involved the temporary raising of Warren Weir and the installation of temporary structures to block flow at Crooked Creek and Duck Creek regulators. Stage 2 involves a bulk water transfer from Windamere Dam to Burrendong Dam and is anticipated for late 2019. Stage 3 (the proposal) is proposed to access the deep water storage at Burrendong Dam.

This includes temporary works to supply water to communities that rely on surface water delivered from Burrendong Dam. Current water storage levels of the Burrendong Dam are at critical levels being measured at 4.4% (18 September 2019). Once at 0% the dam has approximately 21.5 GL of deep-water storage.

To date, management of the storages and river system has delayed the worst effects of the drought. Under the assumption of no significant rainfall, no inflow to the river system, and in the absence of further drought contingency measures and drought response works, flows in the Macquarie River would be expected to cease by January 2020. With the implementation of further contingency and temporary works ceases to flow are expected to be delayed until the end of September 2020 (Depletion Curve, River Operations Stakeholder Consultation Committee (ROSCCo) notes 29 Jul 2019).

1.2 Purpose of this report

The purpose of this report, which will be appended to, and summarised in the Review of Environmental Factors (REF), is to assess the potential impacts of the proposal on water quality and aquatic ecology in Burrendong Dam and the Macquarie River.


1.3 Scope and limitations

This report has been prepared by GHD for WaterNSW and may only be used and relied on by WaterNSW for the purpose agreed between GHD and the WaterNSW as set out in Section 1.2 of this report.

GHD otherwise disclaims responsibility to any person other than WaterNSW arising in connection with this report. GHD also excludes implied warranties and conditions, to the extent legally permissible.

The services undertaken by GHD in connection with preparing this report were limited to those specifically detailed in the report and are subject to the scope limitations set out in the report.

The opinions, conclusions and any recommendations in this report are based on conditions encountered and information reviewed at the date of preparation of the report. GHD has no responsibility or obligation to update this report to account for events or changes occurring subsequent to the date that the report was prepared.

The opinions, conclusions and any recommendations in this report are based on assumptions made by GHD described in this report. GHD disclaims liability arising from any of the assumptions being incorrect.

GHD has prepared this report on the basis of information provided by WaterNSW and others who provided information to GHD, which GHD has not independently verified or checked beyond the agreed scope of work. GHD does not accept liability in connection with such unverified information, including errors and omissions in the report which were caused by errors or omissions in that information.

The opinions, conclusions and any recommendations in this report are based on information obtained from, and testing undertaken at or in connection with, specific sample points. Site conditions at other parts of the site may be different from the site conditions found at the specific sample points.

Investigations undertaken in respect of this report are constrained by the particular site conditions, such as the location of buildings, services and vegetation. As a result, not all relevant site features and conditions may have been identified in this report.

Site conditions (including the presence of hazardous substances and/or site contamination) may change after the date of this Report. GHD does not accept responsibility arising from, or in connection with, any change to the site conditions. GHD is also not responsible for updating this report if the site conditions change.


2. Methodology 2.1 Sites visited

Two sites were visited on 28 August 2019:

Burrendong Dam, near the deep water storage area

Macquarie River, directly downstream of the dam outlet

The locations of these sites are shown in Figure 2-1 below.

2.2 Water quality sampling

2.2.1 In situ water quality

The following in situ physical and chemical parameters were measured both sites using a YSI ProDSS multi-parameter water quality meter:

Temperature (°C)

pH (pH units)

Electrical Conductivity (EC) (µS/cm)

Dissolved Oxygen (DO) (mg/L and % saturation)

The meter was calibrated prior to use.

2.2.2 Laboratory analysis

One water sample was collected at each site. Samples requiring analysis of dissolved metals and dissolved organic carbon (DOC) were field filtered using a dedicated high volume 45 µm filter prior to collection in the sample bottle. Water samples were analysed for the parameters in Table 2-1 by a NATA accredited laboratory. The laboratory certificate of analysis (COA) is provided in Appendix A.

Table 2-1 Analytical schedule - water samples

Suite Analytes Physicochemical parameters

pH, EC, total dissolved solids (TDS), total suspended solids (TSS), total hardness, turbidity

Anions Chloride, sulfate, alkalinity, silicon, fluoride Cations Calcium, magnesium, sodium, potassium Metals (dissolved and total)

Aluminium, arsenic, cadmium, chromium, copper, lead, nickel, selenium, zinc, iron, mercury

Nutrients Total nitrogen (TN), nitrate, nitrite, NOx, TKN, ammonia, total phosphorus (TP), reactive phosphorous

Other analytes DOC, Chlorophyll-a

2.3 Habitat assessment

Visual estimates of the following characteristics of each site were recorded:

Stream bed composition

Aquatic and riparian vegetation cover

Amount of in-stream detritus

Aquatic micro-habitat types


Modified Riparian, Channel, and Environmental Inventory (Chessman et al. 1997 and Peterson 1992) field sheets were completed at each site. The modified RCE assesses aquatic and riparian habitats against thirteen categories providing a score ranging from 0 to 4 for each category. Each score in each category has a description of habitat condition which provides a consistent basis to descriptively assess and compare individual sites. Higher scores indicate better quality, less disturbed habitats, and the total score provides an overall assessment of habitat conditions. The RCE statuses associated with different ranges of RCE total scores are presented in Table 2-2.

Table 2-2 Modified RCE total score and statuses

RCE total score RCE status 0-11 Poor 12-21 Fair 22-31 Good 32-41 Very good 42-52 Excellent

Field data were recorded by a qualified and experienced aquatic ecologist.

2.4 Fish community assessment

2.4.1 Species list

A list of the fish species likely to be present in Burrendong Dam and the downstream reaches of the Macquarie River was compiled using the following information and data:

Department of Primary Industries Fisheries (DPIF) distribution data

Results from the IWRA 2018 Lake Burrendong Classic angling competition, available at: http://www.iwra.com.au/news/results-2018-lake-burrendong-classic

2.4.2 Environmental tolerances

A literature review was undertaken to understand the range of environmental tolerances of the fish communities in Burrendong Dam and Macquarie River based on the developed species list.

2.5 Data analysis

Water quality results were compared to the Australian and New Zealand Guidelines for Fresh and Marine Water Quality. The following default guideline values (DGVs) were used to assess water quality:

Default DGV ranges for physical and chemical stressors outlined in Table 3.3.2 of the ANZECC (2000) guidelines

Default guideline value ranges for conductivity (EC) and turbidity outlined in Table 3.3.3 of the ANZECC (2000) guidelines

Toxicant DGVs for protection of 95 percent of freshwater species as outlined in ANZG (2018)

Dissolved metal and metalloid concentrations are more applicable for comparison to the water quality DGVs than total metals, as they are more representative of the bioavailable fractions of metals and metalloids within the water. Therefore, only dissolved metal concentrations have been assessed against the water quality DGVs.


2.6 Quality assurance

In accordance with GHD’s Quality Assurance (QA) protocol, duplicate water samples were collected at the same time as the collection of the primary samples at the Burrendong Dam site. The collection of duplicate water samples allows for the assessment of the potential level of uncertainty associated with sampling method, preservation, transport or laboratory analysis. The results of the duplicate samples are presented in Appendix B.

Burrendong DamMacquarie River

FIGURE 2-1

0 0.8 1.6 2.4 3.2

Kilometres


12512398

Date 29/10/2019

WaterNSWBurrendong Dam Deep Water Storage Access

Water Quality and AquaticEcology Impact Assessment


Paper Size ISO A4

oData source: sixmaps/LPI_Imagery_Best: © Department of Finance, Services & Innovation 2017. LPI, DTDB, 2017. Created by: fmackayN:\AU\Orange\Projects\22\12512398\GIS\Maps\Deliverables\WQAE_0.aprx\12512398_WQAE001_Location_0

Print date: 29 Oct 2019 - 08:51

Legend

Watercourses

Sites visited on 28 August 2019


3. Existing conditions 3.1 Water quality

3.1.1 In situ water quality

The in situ water quality results from 28 August 2019 are presented in Table 3-1. These results indicate that dissolved oxygen concentrations in the dam are currently high, and are supersaturated in the Macquarie River downstream of the outlet, which is likely associated with the physical aeration of the released water.

EC in the dam exceeded the DGV for freshwater reservoirs, though in the Macquarie River the similar EC value was below the DGV for lowland rivers.

The observed Oxidation-reduction potential (ORP) values indicated oxidative conditions at both sites.

Table 3-1 In situ water quality results, 28 August 2019

Parameter Units Burrendong Dam

Macquarie River

DGV Freshwater reservoirs

Lowland rivers

Temperature °C 11.9 11.6 NA NA DO % Sat. 94.6 114.2 90-110 85-110

mg/L 10.17 12.23 NA NA EC µS/cm 457.5 459.5 20-30 125-2200 pH pH units 8.39 8.42 6.5-8.0 6.5-8.5 ORP mV 161.2 162.1 NA NA

3.1.2 Laboratory analysis

The results of laboratory analyses of the samples collected on 28 August 2019 are presented in Table 3-2. These results indicate that TSS concentrations and turbidity values were low at both sites. The dominant major ions in the dam were calcium and bicarbonate.

Low concentrations of dissolved heavy metals were observed, with the nickel being the only metal observed at or above its laboratory limit of reporting (LOR). No exceedances of the DGVs for metal toxicants were observed.

Elevated nutrient concentrations were observed at both sites. This included exceedances of the DGVs for NOx and TN at both sites, and for TP in the dam. The DGVs for these parameters are associated with the risk of nuisance algal blooms. TKN concentrations indicated that the majority of the nitrogen at both sites is present as organic nitrogen, followed by NOx and ammonia. RP (orthophosphate) concentrations at both sites were below the laboratory LOR, which indicates that algal growth in the dam is likely phosphorous limited, as orthophosphate is the only form of phosphorous that autotrophs can assimilate (Correll 1999).

DOC concentrations at both sites were relatively high, which indicates the potential risk of low DO concentrations, as decomposition of DOC consumes DO.

Chlorophyll a concentrations, which are regularly used as a proxy for phytoplankton biomass (Huot et al. 2007), were below the DGV at both sites.


Table 3-2 Results of laboratory analysis of samples collected 28 August 2019


Macquarie River

DGV Freshwater reservoirs

Lowland rivers

Physicochemical parameters TSS mg/L 5 <5 5 NA NA Turbidity NTU 0.1 2 1.8 20 50 Major ions Chloride mg/L 1 42 40 NA NA Sulfate as SO4 mg/L 1 38 39 NA NA Total alkalinity as CaCO3

mg/L 1 118 118

NA NA

Calcium mg/L 1 36 34 NA NA Magnesium mg/L 1 18 17 NA NA Sodium mg/L 1 33 32 NA NA Potassium mg/L 1 5 5 NA NA Dissolved metals Aluminium mg/L 0.01 <0.01 <0.01 0.055 0.055 Arsenic mg/L 0.001 <0.001 <0.001 0.013 0.013 Cadmium mg/L 0.0001 <0.0001 <0.0001 0.0002 0.0002 Chromium mg/L 0.001 <0.001 <0.001 0.001 0.001 Copper mg/L 0.001 <0.001 <0.001 0.0014 0.0014 Lead mg/L 0.001 <0.001 <0.001 0.0034 0.0034 Nickel mg/L 0.001 <0.001 0.001 0.011 0.011 Selenium mg/L 0.01 <0.01 <0.01 0.011 0.011 Zinc mg/L 0.005 <0.005 <0.005 0.008 0.008 Iron mg/L 0.01 <0.05 <0.05 NA NA Mercury mg/L 0.0001 <0.0001 <0.0001 0.0006 0.0006 Nutrients Ammonia as N mg/L 0.01 0.1 0.12 0.900 0.900 NOx as N mg/L 0.01 0.16 0.2 0.010 0.040 TKN as N mg/L 0.1 0.7 0.4 NA NA TN as N mg/L 0.1 0.9 0.6 0.350 0.040 TP as P mg/L 0.01 0.04 <0.01 0.010 0.050 RP as P mg/L 0.01 <0.01 <0.01 0.005 0.020 Other DOC mg/L 1 10 10 NA NA Chlorophyll a mg/L 0.001 0.004 0.002 0.005 0.005

3.1.3 WaterNSW supplied data

In situ profiler data 13 September 2019

The temperature profile in Burrendong Dam on 13 September 2019 is presented as Figure 3-1. This figure shows that water in the dam was stratified by temperature, with water at 16 metres below the surface being slightly over 2 degrees Celsius colder than that at the surface.

Figure 3-2 shows that DO saturation was highest at the surface of the dam, and decreased gradually with depth, though anoxic conditions were not observed even at the lowest depth (16 metres).


pH was about 8.4 at the surface of the dam, and reduced to 8.0 at a depth of 16 metres (Figure 3-3) this spatial trend is likely associated with algal photosynthesis being greatest at the surface, which removes dissolved carbon dioxide and results in bicarbonate being more dominant, thus affecting pH.

Figure 3-4 shows that turbidity increases with depth in the dam, though none of the turbidity values observed pose any risk for aquatic life.

Figure 3-1 Temperature profile in Burrendong Dam, 13 September 2019

Figure 3-2 DO profile in Burrendong Dam, 13 September 2019


Figure 3-3 pH profile in Burrendong Dam, 13 September 2019

Figure 3-4 Turbidity profile in Burrendong Dam, 13 September 2019

Depth profile chemistry and algae data

Figure 3-5 shows the concentrations of major cations (calcium, magnesium, sodium and potassium) at depths in Burrendong Dam between the surface and 30 metres. The sampling was undertaken on three occasions, in October, November and December 2017. These data indicate that there was no salinity stratification observed in the dam. This is also shown by Figure 3-6, which shows that there were no spatial trends in the concentrations of the major anions chloride, sulfate and bicarbonate.

TN concentrations were shown to generally increase with depth in Burrendong Dam (Figure 3-7). This may the effect of biomass incorporation of nitrogen, which would be likely to be greater near the surface of the dam due to higher algae densities. No similar trend in TP concentrations was observed (Figure 3-8), which likely indicates that the majority of the phosphorous present was not available for assimilation by autotrophs.


Figure 3-9 shows that total algae and total cyanobacteria counts were highest in December 2017, and for each profile were highest towards the surface of the dam. These observations are to be expected based on light availability. Figure 3-10 and Figure 3-11 show that the algal and cyanobacterial biovolumes were highest in December 2017, at three metres below the surface of the dam.

Figure 3-5 Major cation depth profiles in Burrendong Dam

Figure 3-6 Major anion depth profiles in Burrendong Dam


Figure 3-7 Total nitrogen depth profiles in Burrendong Dam

Figure 3-8 Total phosphorous depth profiles in Burrendong Dam

Figure 3-9 Total algae and cyanobacteria depth profiles in Burrendong Dam


Figure 3-10 Algal biovolume depth profiles in Burrendong Dam

Figure 3-11 Cyanobacterial biovolume depth profiles in Burrendong Dam

Time-series algae data

Figure 3-12 shows total algae counts in Burrendong Dam since 2015. This indicates that a peak in the total algae counts has been observed in the summer of each year, with the highest summer peak being observed in March 2019. However, the highest algae concentration was observed recently in August 2019. Figure 3-13 shows that cyanobacteria counts have followed similar trends, and that the recent elevated algae concentration was mostly cyanobacteria.

Figure 3-14 and Figure 3-15 show that algal and cyanobacterial biovolume have followed similar trends to the total cell counts, which is as expected.


Figure 3-12 Total algae counts in Burrendong Dam since 2015

Figure 3-13 Total cyanobacteria counts in Burrendong Dam since 2015

Figure 3-14 Algal biovolume in Burrendong Dam since 2015


Figure 3-15 Cyanobacterial biovolume in Burrendong Dam since 2015

3.2 Aquatic habitat

Burrendong Dam and the Macquarie River is mapped as Key Fish Habitat (Department of Primary Industries (DPI), 2019) by the NSW Department of Primary Industries. Threatened species distribution mapping produced by DPI (2019) identify indicative habitat for Eel Tailed Catfish, Olive Perchlet, Silver Perch and Trout Cod within the vicinity of the proposal. Murray Cod is also known to be present and is listed as vulnerable under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act).

Key observations from the habitat assessment on 28 August 2019 are presented in Table 3-3, along with site photos.

The results of the RCE assessment are presented in Table 3-4, which indicates that the aquatic habitat in Macquarie River downstream of Burrendong Dam is in better condition than that of the dam. It is noted that some of the RCE categories are not as appropriate for dams as for rivers, e.g. channel form and riffle/pool sequence. Regardless, these results give an indication of the aquatic habitat in each of the monitoring locations.


Table 3-3 Photos and habitat observations, 28 August 2019

Burrendong Dam

1) Looking south east

2) Looking east

3) Looking west

As seen in photos 1 and 3, the substrate in Burrendong Dam is comprised of a mix of silt, sand, gravel and pebbles, with some cobbles present. Much of the substrate is covered with filamentous algae, with no macrophytes present. Some early growth of Azolla sp.was present (photo 2), however this appeared to be limited to the area around the offtake infrastructure. Elevated algae concentrations were indicated by the green colour of the water as seen in Photo 1. There was little submerged woody habitat (SWH) available, as it was limited to the occasional branch, as seen in Photo 3 for example. Due to the low water level in the dam, there was very little riparian vegetation near the edge of the surface water and as a result, minimal shading.


Macquarie River

4) Looking downstream

5) Looking upstream

6) Taken looking across the river

The substrate in the Macquarie River directly downstream of Burrendong dam is mostly comprised of cobbles, as seen in photos 4 to 6. The cobbles were covered in filamentous algae, and long strands of this algae were observed in the faster flowing sections of the river, as shown in photo 6. Both pool and riffle habitats were observed, and submerged woody habitat was also abundant. Riparian vegetation was dominated by eucalypts on the left bank and casuarinas on the right, providing a high degree of shading to the edges of the river. As was observed for Burrendong Dam, the green colour of the water indicated elevated algae concentrations.


Table 3-4 Results of the RCE assessment

RCE Category Burrendong Dam

Macquarie River

Land-use pattern beyond immediate riparian zone 3 3 Width of riparian strip of woody vegetation 0 3 Completeness of riparian strip of woody vegetation 0 3 Vegetation of the riparian zone within 10 m of channel 1 3 Stream bank structure 3 4 Bank undercutting 4 4 Channel form 4 3 Riffle/pool sequence 2 4 Retention devices in stream 2 3 Channel sediment accumulation 2 4 Stream bottom 2 3 Stream detritus 2 3 Aquatic vegetation 3 3 RCE total score 28 43 RCE status Good Excellent

3.3 Fish community

DPIF sampled fish communities as part of a Short-term intervention monitoring of a fish community response to an environmental flow in the mid and lower Macquarie River: 2014/15 water year (DPI 2016). This involved sampling in four spatially, geomorphologically and hydrologically different zones at a landscape scale:

Zone 1: Macquarie River Burrendong Dam to Dubbo – about a 100 kilometre long stretch of river.

Zone 2: Macquarie River Gin Gin to Warren – about a 100 kilometre long stretch of river upstream of the Macquarie Marshes. The majority of Zone 2 is upstream of the Warren Weir and is included sampling between the Warren Weir and Gin Gin Weir.


Zone 4: Lower Macquarie River (below the Macquarie Marshes). This is about a 100 kilometre long stretch of the river between Bells Bridge and the Barwon River confluence. Sampling was not undertaken at some sites in Zone 4 during two of the three sampling events because the river was dry.

In general, this study concluded that native fish species richness was significantly lower within, and downstream of, the Macquarie Marshes compared with sites sampled upstream. The overall condition of the fish community within the Macquarie River declined along a downstream gradient from ‘poor’ below Burrendong Dam to ‘extremely poor’ in the Macquarie Marshes and downstream to the Barwon River confluence.

Threatened fish species recorded by DPIF included:

Murray Cod – this is listed as vulnerable under the EPBC Act. This species was recorded in Zones 1 (12 records), 2 (214 records) and 3 (19 records). This reflects that the highest abundances were recorded from Gin Gin to Warren.

Silver Perch – this is listed as vulnerable under the FM Act and critically endangered under the EPBC Act. This species was recorded once and that was in Zone 2.


Trout Cod – this is listed as endangered under the FM Act and EPBC Act. This species was recorded once in Zone 1.

Eel Tailed Catfish – This species is an endangered population under the FM Act and was recorded in Zones 1 (24 records) and 2 (3 records).

3.3.1 Species list

The list of fish species likely to be present in Burrendong Dam and Macquarie River downstream of the dam is presented in Table 3-5.

Table 3-5 List of fish species likely to be present in Burrendong Dam and Macquarie River downstream of the dam.

Common name Scientific name Exotic/Endemic Conservation status

Comments on presence in Burrendong Dam and Macquarie River

Murray Cod Maccullochella peelii peelii

Endemic Vulnerable (EPBC Act)

Known presence

(Golden Perch) Yellow Belly

Macquaria ambigua

Endemic Not listed Known presence

Redfin Perca fluviatilis Endemic NA Known presence

Eel Tailed Catfish

Tandanus tandanus

Endemic Endangered (FM Act)

Known presence

Silver Perch Bidyanus bidyanus

Endemic Critically endangered (EPBC Act) Vulnerable (FM Act)

Known presence, though limited observations in Macquarie river

Rainbow Trout Oncorhynchus mykiss

Exotic NA Known presence

Brown Trout Salmo trutta Exotic NA Known presence

Trout Cod Maccullochella macquariensis

Endemic Endangered (EPBC Act and FM Act)

Likely presence – stocking was undertaken in 2018

European Carp Cyprinus carpio Exotic NA Known presence

3.3.2 Water quality preferences/tolerances

A literature review was undertaken to establish the water quality preferences and tolerances of the endemic species likely to be present in Burrendong Dam and the Macquarie River. Table 3-6 summarises the results of this review.


Table 3-6 Water quality preferences and tolerances of native fish likely in Burrendong Dam and Macquarie River.

Common name

Scientific name

Water quality preferences/tolerances

Reference(s)

Murray Cod

Maccullochella peelii

Salinity above 0.34 g/L may result in significant impacts on Murray Cod Ideal pH between 6-

8 dissolved oxygen

ideally above 3 mg/L. Lethal below 1.58 mg/L

Free ammonia ideally <0.1 mg/L

National Murray Cod Recovery Team 2010. National Recovery Plan for the Murray Cod Maccullochella peelii peelii. Department of Sustainability and Environment, Melbourne. https://www.dpi.nsw.gov.au/fishing/aquaculture/publications/species-freshwater/murray-cod-aquaculture-prospects Small et al. (2014)

(Golden Perch) Yellow Belly

Macquaria ambigua

Tolerates temperature between 4-35°C

DO lethal below 0.85 mg/L

https://waterqualitysolutions.com.au/best-fish-to-stock-in-your-dam/ Small et al. (2014)

Eel Tailed Catfish

Tandanus tandanus

DO lethal below 0.26 mg/L

Small et al. (2014)

Silver Perch

Bidyanus bidyanus

Prefers temperature between 20-35 °C

Prefers DO >4 mg/L, lethal <1.04 mg/L

Ammonia levels of <0.1 mg/L, growth reduced at 0.36 un-ionised ammonia.

Prefers pH 6-10

https://www.business.qld.gov.au/industries/farms-fishing-forestry/fisheries/aquaculture/species/silver-perch/culture-environment Small et al. (2014)

Trout Cod Maccullochella macquariensis

No data found

3.3.3 Biomass estimate

WaterNSW have estimated the fish biomass in Burrendong Dam at full storage to be 10-20 kg/hectare. Under existing conditions a much higher density of fish is expected considering the reduced area of the water body.

3.3.4 Removed exotic species

WaterNSW engaged a commercial fisherman to remove European Carp from Burrendong Dam to reduce the fish biomass in the Dam. As of 13 September 2019, about 100 kg of Carp had been removed. The commercial fishing ceased due to the low yield. WaterNSW may engage a commercial operator to recommence carp fishing once water levels recede as this is likely to increase the catch rate.


4. Impact assessment 4.1 Water quality


Potential impacts to surface water quality during construction would be limited to activities associated with the installation of new infrastructure and construction of the coffer dam at Burrendong Dam.

The installation of the aeration system aims to reduce water quality risks to the deep water storage through oxygenation and circulation. The aeration system consists of air compressors housed in a small building above the dam maximum water level with associated equipment and pipework leading down into the deep water storage.

The construction of the coffer dam involves constructing an earth embankment to create a small basin around the outlet tower. The construction will be undertaken in three phases:

1. Install a silt curtain in the water to minimise the risk of residual debris and silt reaching surrounding areas of the waterway

2. Construct the first half of the coffer dam with a culvert with penstock to allow flows post construction

3. Construct second half of the coffer dam with the use of the culvert and penstock to allow flows during the second half of the coffer dam to be completed.

An excavator will undertake works within Burrendong Dam to install the coffer dam. The excavator will use material from the existing borrow area located adjacent to the proposed coffer dam.

The installation of a pump station and associated pipelines involves six partially submerged pumps on two prefabricated pontoons

Works within the waterway pose the following risks to water quality during construction:

Fuel spills entering the dam

Sediment (soil, gravel, concrete washings) entering the dam and increasing turbidity

These impacts will be short term and limited to the five month construction period. Management measures will be implemented to minimise potential impacts.

There is potential for erosion and subsequent sedimentation and an increase in turbidity within the vicinity of works to construct the coffer dam. The risk of increased turbidity in the dam to the extent that there would be adverse impacts on aquatic fauna is considered low.

There is a risk that spills of fuel, hydraulic fluids and lubricating oils used in construction equipment could release hydrocarbons and metals into the environment. Spill containment measures (such as drip trays) will be used where refuelling within 40 metres of the dam is required, where possible refuelling greater than 40 metres from the dam will occur. Fuels and oils used on pontoons would be stored in appropriately bunded areas. It is unlikely that the water quality will be significantly impacted provided the mitigation measures detailed in Section 5.2 are implemented.

Given the small area of soil that would be disturbed, any increased risk of water quality being impacted by turbid runoff from exposed areas is unlikely. Monitoring of weather and rainfall events will occur as well as river levels upstream to ensure that the work site is closed prior to any tributary flows occurring that have the potential to inundate work areas.


The Macquarie River Catchment can experience large flood events, however there is significant notice of any tributary flows that have the potential to result in flooding. The proposal would take place during a severe drought and Burrendong Dam is currently at 4.4 % capacity (19 September 2019). If there is a significant rain event, there is ample capacity within Burrendong Dam to capture flows to mitigate the effects of flooding. If significant rainfall occurs that leads to large tributary flows upstream of Burrendong Dam, WaterNSW will suspend construction and move equipment to a location that is unlikely to be affected by rising water levels. If there is substantial inflow to the storage that has the potential to inundate the work site, it is likely that the temporary drought response measures would be deferred in any case.

As construction will involve activities that are classified as dredging and reclamation, WaterNSW is required to notify the DPIF under section 199 of the Fisheries Management Act 1994. Matters raised by the DPIF within 21 days of the notification being given are required to be taken into consideration.

Operational impacts

The proposal will extend the duration that there would be flows in the Macquarie River downstream of Burrendong Dam, and due volumes provided and the aeration received at the dam outlet, the water quality of these flows would be supportive of aquatic life in the downstream habitats.

Figure 4-1 shows the anticipated extent of the 20 GL deep storage and the 6 GL draw down level that would remain. This figure also shows upstream extent of the reservoir that WaterNSW anticipates is likely to benefit from operation of the aeration system.

In the 6 GL of deep storage in Burrendong Dam proposed to be maintained for the fish community present, evapo-concentration is unlikely to be of concern, as, based on the existing water quality, even a 10 fold increase in parameter concentrations (i.e. evaporation of 90 percent of the 6 GL) would not result in any potentially ecotoxic concentrations of metals.

Elevated nutrient concentrations in Burrendong Dam could be observed as a result of the following:

Evapo-concentration

Decomposition of organic matter present in the deep water storage

Inflows of water with elevated nutrient concentrations or elevated organic matter concentrations, which could lead to elevated concentrations through decomposition

The potential impacts of elevated nutrient concentrations include nuisance algal blooms and the associated risk of low DO saturations, and potential toxicity to aquatic life due to ammonia toxicity. These impacts are unlikely because the aeration system is expected to minimise the risk of the development of hypoxic conditions in the deep water storage, and the high DO saturations provided by the system will likely prevent the build-up of ammonia nitrogen, which will be removed from the system through nitrification and biomass incorporation.

The aeration system is also likely to prevent low DO concentrations following a potential dam turnover event. In the case of such an event, the lower layer of water would be oxygenated, in contrast to a turnover event under the do-nothing scenario, which would result in lower anoxic water being brought to the surface of the dam.

FIGURE 3.

0 350 700 1,050 1,400

Meters


12512398

Date 13/11/2019




Paper Size ISO A4

oData source: LPI ,DCDB, 2017. . Created by: TMortonN:

\AU\Orange\Projects\22\12512398\GIS\Maps\Deliverables\REF_Final_0.aprx\12512398_REF006_DeepStorageCompa_0Print date: 13 Nov 2019 - 18:37

Anticipated surface area of the 20 GLdeep storage compared to the 6 GL

draw down lever

Legend

Anticipated upstream area benefittingfrom the aeration systen

Figure 4.1


4.2 Aquatic Ecology


The proposal will have a localised disturbance footprint over the five month short construction timeframe. Impacts to aquatic habitat in Burrendong Dam are likely to be negligible during construction.

Potential indirect effects on aquatic habitat during construction include the following:

Erosion and sedimentation: uncontrolled erosion of soil from the proposal site and the corresponding deposition of this material in the deep storage area. This process could reduce aquatic habitat values in the deep storage area.

Pollutants: Water quality impacts could occur during construction if fuel or chemical spills from construction vehicles or equipment enter the deep storage area.

Construction impacts will be minimised by implementing the mitigation measures in Section 5.2 and are unlikely to be significant.

Operational impacts

The proposal will have substantial beneficial ecological impacts by maintaining flows within the section of the Macquarie River downstream of Burrendong Dam, which provides habitat for threatened fish species such as Murray Cod, Silver Perch and Eel-tailed Catfish. The section of the Macquarie River near Dubbo also has a population of Trout Cod, which is listed as endangered under the EPBC Act and FM Act. Maintaining flows in the river will also reduce the risk of pools stagnating and the development of poor water quality that has the potential to impact on aquatic ecology. Assessments of significance for the EPBC Act and FM Act listed fish species have been provided in Appendix C.

The proposal will reduce the habitat availability for the fish community in Burrendong Dam, however, compared to the do-nothing scenario, the habitat quality in the deep water storage will be improved because:

The aeration system will maintain DO levels above the lethal thresholds for native species, the highest being 1.58 mg/L for Murray Cod

Exotic European Carp are being removed from Burrendong Dam, thus reducing competition with native species

Any dead fish will be quickly removed from the deep water storage, minimising the potential impact on organic carbon and nutrient concentrations

As discussed in Section 4.1, the proposal has the potential to adversely impact water quality, primarily in the deep water storage. The most likely impacts are elevated EC and concentrations of nutrients and organic carbon. The EC of Burrendong Dam exceeds the DGV under existing conditions, and any increase in EC through evapoconcentration is unlikely to have lethal effects on the fish population, though elevated EC may act as a stressor for some fish including Murray Cod.

Elevated nutrient concentrations have the following potential adverse effects on aquatic life:

Elevated concentrations of ammonia can result in acute and chronic toxicity

Elevated nutrient concentration can promote nuisance algal blooms, which can result in anoxia and fish kills

Algal scum or dense Azolla sp. coverage can prevent light penetration and thereby limit oxygenation of deeper water through photosynthesis


All reasonable and feasible management measures will be implemented to minimise the potential impacts of the proposal. This will include a Water Quality Monitoring Plan and Fish Monitoring Plan developed in consultation with relevant government agencies, such as the DPIE-W, DPIF, NRAR and DPIE. The proposal will maintain a larger area of higher quality aquatic habitat downstream of Burrendong Dam than that which would be maintained in Burrendong Dam under the do-nothing scenario.

4.2.1 Biomass estimate

Based on the area of the water body available when 6 GL remain in the damn, the biomass predicted based on that of the dam at full storage level is between 500 and 1000 kg/hectare. While this is a conservative level estimate, it indicates that the biomass in the deep water storage has the potential to become unsustainable, considering that tropical coastal wetlands in Australia, which are more productive than freshwater rivers, support up to 290 kg of fish biomass per hectare.


5. Management, monitoring and

mitigation measures 5.1 Monitoring

A Water Quality Monitoring Plan and a Fish Monitoring Plan will be developed in consultation with relevant government agencies, such as the DPIE-W, DPIF, NRAR and DPIE.

The Water Quality Monitoring Plan will include:

Continued depth profiler monitoring of temperature, DO, pH and turbidity.

Continued monitoring of EC, and nutrient and organic carbon concentrations.

During construction, monitoring of TSS, dissolved metals, and total recoverable hydrocarbons.

Continued monitoring of algae and cyanobacteria counts and biovolumes.

Visual monitoring of algae as per the Regional Algal Co-ordinating Committee guidelines and WaterNSW service commission deed.

The Fish Monitoring Plan will include:

Daily visual monitoring of the deep water storage for fish deaths, preferably conducted early morning following the most likely time that fish deaths could occur. Dead fish will be removed as soon as practicable.

Regular visual monitoring for moribund fish that could indicate insufficient aeration by the aeration system.

5.2 Mitigation measures

Table 5-1 details the mitigation measures that will be undertaken in response to the potential impacts of the proposal.

Table 5-1 Mitigation measures for potential impacts on water quality and aquatic ecology

Potential impact Mitigation measures Elevated turbidity observed in the deep water storage

Investigate potential causes for the elevated turbidity. Install and maintain sediment control devices between the coffer dam and the deep water storage in line with the Construction Environmental Management Plan.

Low DO saturations in the deep water storage

Investigate efficacy of the aeration system and modify if appropriate.

Elevated nutrient concentrations associated with the risk of algal blooms.

Investigate the monitoring data for trends in nutrient concentrations and assess the effectiveness of the aeration system in maintaining DO levels. If elevated phosphorous concentrations are observed consider use of treatment technologies such as Phoslock.

Algal blooms observed in the deep water storage or the Macquarie River

Monitor DO regularly in the area of the algal bloom to assess the need for localised aeration to prevent fish kills.

Fish kills in the deep water storage or Macquarie River

Remove dead fish as soon as practicable. Investigate water quality data to determine cause of fish deaths and modify the aeration system if appropriate.


Potential impact Mitigation measures Moribund fish observed in the deep water storage

Investigate efficacy of the aeration system and modify if appropriate. Undertake an additional inspection of the deep water storage on the same day to remove any dead fish.

Blackwater event in Burrendong Dam following heavy rainfall.

Assess DO profiler data to determine risk of anoxia. Modify the aeration system if appropriate/possible. Undertake water quality sampling following the event to assess the risk of algal blooms.

Chemical or hydrocarbon spill associated with construction activities

Control, contain and clean-up spill in accordance with the Construction Environmental Management Plan. Undertake additional water quality sampling to verify the efficacy of the clean-up.

The fish biomass in the deep water storage exceeds sustainable levels

Remove as much exotic species biomass as practicable.


6. Conclusions The existing conditions in Burrendong Dam and Macquarie River directly downstream of the dam indicate that water quality is generally protective of aquatic life, with no concentrations of toxicants which are likely to adversely impact aquatic species. Nutrient concentrations are elevated however, and while anoxic conditions have not yet been observed there is the potential for algal blooms to result in reduced dissolved oxygen concentrations and potentially fish kills under the do-nothing scenario which assumes continued extreme drought in the catchment.

Aquatic habitat observed at Burrendong Dam and Macquarie River was classed as good and excellent respectively through Modified Riparian, Channel, and Environmental Inventory assessment. The reaches of the Macquarie River downstream of Burrendong Dam likely support populations of native fish species, including species protected under the EPBC Act and/or the FM Act, such as Murray Cod, Eel Tailed Catfish, Silver Perch and Trout Cod. The proposal will have beneficial ecological impacts by maintaining flows within the section of the Macquarie River downstream of Burrendong Dam, which provides habitat for these protected species.

While the proposal will reduce habitat availability for the fish community in Burrendong Dam, it is predicted that there will also be benefits to water quality and aquatic ecology in the 6 GL which will remain in the deep storage area, due to the aeration system which will be installed, and the proposed mitigation measures, which include exotic biomass minimisation and the removal of any dead fish, in the case that they are observed during regular monitoring. These water quality and aquatic ecology benefits would not be observed under the do-nothing scenario.

Continued extreme drought conditions in the Macquarie River have severe potential impacts on water quality and aquatic ecology in Burrendong Dam and the downstream reaches of the river. The proposal will minimise the impacts in the downstream reaches of the river by maintaining flows, as well as manage and mitigate the potential impacts within the dam, where the proposed mitigation measures are more practical and achievable.


7. References ANZECC&ARMCANZ, 2000, Australian and New Zealand Guidelines for Fresh and Marine Water Quality, Australia and New Zealand Environment and Conservation Council and Agriculture and Resource Management Council of Australia and New Zealand, Canberra.

ANZG, 2018, Australian and New Zealand Guidelines for Fresh and Marine Water Quality: Default Guideline Values, http://www.waterquality.gov.au/anz-guidelines/guideline-values/default

Blaber, S. J. M. (2002). Fish in hot water: the challenge facing fish and fisheries in tropical estuaries. Journal of Fish Biology 61, 1–20.

Chessman, BC, Growns, JE, and Kotlash, AR,1997, Objective derivation of macro-invertebrate family sensitivity grade numbers for the SIGNAL biotic index: application to the Hunter River system, NSW Mar. Freshwater Res. 48: 159-172.

Correll, DL, 1999, Phosphorous: A rate limiting nutrient in surface waters, Poultry Science 78:674-682.

Department of Primary Industries NSW, 2019, Key Fish Habitat Maps for Wellington and Dubbo.

Huot, Y, Babin, M, Bruyant, F, Grob, C, Twardowski, MS, Claustre, H, 2007, Does chlorophyll a provide the best index of phytoplankton biomass for primary productivity studies?. Biogeosciences Discussions, European Geosciences Union, 2007, 4 (2), pp.707-745. hal-00330232f.

National Murray Cod Recovery Team, 2010, National Recovery Plan for the Murray Cod Maccullochella peelii peelii. Department of Sustainability and Environment, Melbourne.

Peterson, 1992, The RCE: a riparian, channel and environmental inventory for small streams in the agricultural landscape. Freshwater Biology, 27, 295-306.

Small, K, Kopf, RK, Watts, RJ, and Howitt, J, 2014, Hypoxia, Blackwater and Fish Kills: Experimental Lethal Oxygen Thresholds in Juvenile Predatory Lowland River Fishes. PLoS ONE 9(4): e94524. doi:10.1371/journal.pone.0094524.

GHD | Report for WaterNSW - Burrendong Deep Water Storage Access, 12512398

Appendices


Appendix A – Certificate of analysis

0 0.00 True

Environmental

CERTIFICATE OF ANALYSISWork Order : Page : 1 of 5ES1927700

:: LaboratoryClient GHD PTY LTD Environmental Division Sydney

: :ContactContact MR JOE CAIRNS Customer Services ES

:: AddressAddress 1/51 GRAHAM STREET

NOWRA NSW, AUSTRALIA 2541

277-289 Woodpark Road Smithfield NSW Australia 2164

:Telephone +61 02 6393 6400 :Telephone +61-2-8784 8555

:Project 12512398 Date Samples Received : 30-Aug-2019 10:00

:Order number Date Analysis Commenced : 30-Aug-2019

:C-O-C number ---- Issue Date : 06-Sep-2019 17:21

Sampler : JOE CAIRNS

Site :

Quote number : EN/005/18

3:No. of samples received

3:No. of samples analysed

This report supersedes any previous report(s) with this reference. Results apply to the sample(s) as submitted. This document shall not be reproduced, except in full.

This Certificate of Analysis contains the following information:

l General Comments

l Analytical Results

Additional information pertinent to this report will be found in the following separate attachments: Quality Control Report, QA/QC Compliance Assessment to assist with

Quality Review and Sample Receipt Notification.

SignatoriesThis document has been electronically signed by the authorized signatories below. Electronic signing is carried out in compliance with procedures specified in 21 CFR Part 11.

Signatories Accreditation CategoryPosition

Ankit Joshi Inorganic Chemist Sydney Inorganics, Smithfield, NSW

Ivan Taylor Analyst Sydney Inorganics, Smithfield, NSW

R I G H T S O L U T I O N S | R I G H T P A R T N E R

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General Comments

The analytical procedures used by the Environmental Division have been developed from established internationally recognized procedures such as those published by the USEPA, APHA, AS and NEPM. In house

developed procedures are employed in the absence of documented standards or by client request.

Where moisture determination has been performed, results are reported on a dry weight basis.

Where a reported less than (<) result is higher than the LOR, this may be due to primary sample extract/digestate dilution and/or insufficient sample for analysis.

Where the LOR of a reported result differs from standard LOR, this may be due to high moisture content, insufficient sample (reduced weight employed) or matrix interference.

When sampling time information is not provided by the client, sampling dates are shown without a time component. In these instances, the time component has been assumed by the laboratory for processing

purposes.

Where a result is required to meet compliance limits the associated uncertainty must be considered. Refer to the ALS Contact for details.

CAS Number = CAS registry number from database maintained by Chemical Abstracts Services. The Chemical Abstracts Service is a division of the American Chemical Society.

LOR = Limit of reporting

^ = This result is computed from individual analyte detections at or above the level of reporting

ø = ALS is not NATA accredited for these tests.

~ = Indicates an estimated value.

Key :

EG020: It is recognised that total concentration is less than dissolved for some metal analytes. However, the difference is within experimental variation of the methods.l

EA016: Calculated TDS is determined from Electrical conductivity using a conversion factor of 0.65.l

Sodium Adsorption Ratio (where reported): Where results for Na, Ca or Mg are <LOR, a concentration at half the reported LOR is incorporated into the SAR calculation. This represents a conservative approach

for Na relative to the assumption that <LOR = zero concentration and a conservative approach for Ca & Mg relative to the assumption that <LOR is equivalent to the LOR concentration.

l

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Analytical Results

--------MALRVDUPBDSClient sample IDSub-Matrix: WATER

(Matrix: WATER)

--------28-Aug-2019 09:0028-Aug-2019 08:3028-Aug-2019 08:00Client sampling date / time

----------------ES1927700-003ES1927700-002ES1927700-001UnitLORCAS NumberCompound

Result Result Result ---- ----

EA005P: pH by PC Titrator

7.73 7.80 7.82 ---- ----pH Unit0.01----pH Value

EA006: Sodium Adsorption Ratio (SAR)

1.12^ 1.12 1.12 ---- -----0.01----Sodium Adsorption Ratio

EA010P: Conductivity by PC Titrator

477 474 475 ---- ----µS/cm1----Electrical Conductivity @ 25°C

EA016: Calculated TDS (from Electrical Conductivity)

310 308 309 ---- ----mg/L1----Total Dissolved Solids (Calc.)

EA025: Total Suspended Solids dried at 104 ± 2°C

<5 ---- ---- ---- ----mg/L5----Suspended Solids (SS)

---- <5 5 ---- ----mg/L5----Suspended Solids (SS)

EA045: Turbidity

2.0 5.6 1.8 ---- ----NTU0.1----Turbidity

EA065: Total Hardness as CaCO3

164 164 155 ---- ----mg/L1----Total Hardness as CaCO3

ED037P: Alkalinity by PC Titrator

<1Hydroxide Alkalinity as CaCO3 <1 <1 ---- ----mg/L1DMO-210-001

<1Carbonate Alkalinity as CaCO3 <1 <1 ---- ----mg/L13812-32-6

118Bicarbonate Alkalinity as CaCO3 122 118 ---- ----mg/L171-52-3

118 122 118 ---- ----mg/L1----Total Alkalinity as CaCO3

ED041G: Sulfate (Turbidimetric) as SO4 2- by DA

38Sulfate as SO4 - Turbidimetric 40 39 ---- ----mg/L114808-79-8

ED045G: Chloride by Discrete Analyser

42Chloride 40 40 ---- ----mg/L116887-00-6

ED093F: Dissolved Major Cations

36Calcium 36 34 ---- ----mg/L17440-70-2

18Magnesium 18 17 ---- ----mg/L17439-95-4

33Sodium 33 32 ---- ----mg/L17440-23-5

5Potassium 5 5 ---- ----mg/L17440-09-7

EG020F: Dissolved Metals by ICP-MS

<0.01Aluminium <0.01 <0.01 ---- ----mg/L0.017429-90-5

<0.001Arsenic <0.001 <0.001 ---- ----mg/L0.0017440-38-2

<0.0001Cadmium <0.0001 <0.0001 ---- ----mg/L0.00017440-43-9

<0.001Chromium <0.001 <0.001 ---- ----mg/L0.0017440-47-3

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Analytical Results


(Matrix: WATER)




EG020F: Dissolved Metals by ICP-MS - Continued

<0.001Copper <0.001 <0.001 ---- ----mg/L0.0017440-50-8

<0.001Nickel 0.001 0.001 ---- ----mg/L0.0017440-02-0

<0.001Lead <0.001 <0.001 ---- ----mg/L0.0017439-92-1

<0.01Selenium <0.01 <0.01 ---- ----mg/L0.017782-49-2

<0.005Zinc <0.005 <0.005 ---- ----mg/L0.0057440-66-6

<0.05Iron <0.05 <0.05 ---- ----mg/L0.057439-89-6

EG020T: Total Metals by ICP-MS

0.04Aluminium 0.04 0.06 ---- ----mg/L0.017429-90-5

<0.001Arsenic <0.001 <0.001 ---- ----mg/L0.0017440-38-2

<0.0001Cadmium <0.0001 <0.0001 ---- ----mg/L0.00017440-43-9

0.004Chromium <0.001 <0.001 ---- ----mg/L0.0017440-47-3

<0.001Copper <0.001 0.001 ---- ----mg/L0.0017440-50-8

<0.001Nickel <0.001 <0.001 ---- ----mg/L0.0017440-02-0

<0.001Lead <0.001 <0.001 ---- ----mg/L0.0017439-92-1

<0.01Selenium <0.01 <0.01 ---- ----mg/L0.017782-49-2

<0.005Zinc <0.005 <0.005 ---- ----mg/L0.0057440-66-6

0.13Iron 0.07 0.10 ---- ----mg/L0.057439-89-6

EG035F: Dissolved Mercury by FIMS

<0.0001Mercury <0.0001 <0.0001 ---- ----mg/L0.00017439-97-6

EG035T: Total Recoverable Mercury by FIMS

<0.0001Mercury <0.0001 <0.0001 ---- ----mg/L0.00017439-97-6

EK040P: Fluoride by PC Titrator

0.2Fluoride 0.2 0.2 ---- ----mg/L0.116984-48-8

EK055G: Ammonia as N by Discrete Analyser

0.10Ammonia as N 0.11 0.12 ---- ----mg/L0.017664-41-7

EK057G: Nitrite as N by Discrete Analyser

<0.01Nitrite as N <0.01 <0.01 ---- ----mg/L0.0114797-65-0

EK058G: Nitrate as N by Discrete Analyser

0.16Nitrate as N 0.16 0.20 ---- ----mg/L0.0114797-55-8

EK059G: Nitrite plus Nitrate as N (NOx) by Discrete Analyser

0.16 0.16 0.20 ---- ----mg/L0.01----Nitrite + Nitrate as N

EK061G: Total Kjeldahl Nitrogen By Discrete Analyser

0.7 0.6 0.4 ---- ----mg/L0.1----Total Kjeldahl Nitrogen as N

5 of 5:Page

Work Order :

:Client

ES1927700

12512398:Project

GHD PTY LTD

Analytical Results


(Matrix: WATER)




EK062G: Total Nitrogen as N (TKN + NOx) by Discrete Analyser

0.9^ 0.8 0.6 ---- ----mg/L0.1----Total Nitrogen as N

EK067G: Total Phosphorus as P by Discrete Analyser

0.04 0.03 <0.01 ---- ----mg/L0.01----Total Phosphorus as P

EK071G: Reactive Phosphorus as P by discrete analyser

<0.01Reactive Phosphorus as P <0.01 <0.01 ---- ----mg/L0.0114265-44-2

EN055: Ionic Balance

4.33ø 4.40 4.30 ---- ----meq/L0.01----Total Anions

4.84ø 4.84 4.62 ---- ----meq/L0.01----Total Cations

5.53ø 4.79 3.56 ---- ----%0.01----Ionic Balance

EP002: Dissolved Organic Carbon (DOC)

10 9 10 ---- ----mg/L1----Dissolved Organic Carbon

EP008: Chlorophyll a & Pheophytin a

4 ---- 2 ---- ----mg/m³1----Chlorophyll a


Appendix B – Water quality QA Parameter Units LOR Burrendong Dam Duplicate

Physicochemical parameters pH pH units 0.01 7.73 7.8 EC µS/cm 1 477 474 TSS mg/L 5 <5 <5 Turbidity NTU 0.1 2 5.6 Major ions Chloride mg/L 1 42 40 Sulfate as SO4 mg/L 1 38 40 Total alkalinity as CaCO3 mg/L 1 118 122 Calcium mg/L 1 36 36 Magnesium mg/L 1 18 18 Sodium mg/L 1 33 33 Potassium mg/L 1 5 5 Dissolved metals Aluminium mg/L 0.01 <0.01 <0.01 Arsenic mg/L 0.001 <0.001 <0.001 Cadmium mg/L 0.0001 <0.0001 <0.0001 Chromium mg/L 0.001 <0.001 <0.001 Copper mg/L 0.001 <0.001 <0.001 Lead mg/L 0.001 <0.001 <0.001 Nickel mg/L 0.001 <0.001 0.001 Selenium mg/L 0.01 <0.01 <0.01 Zinc mg/L 0.005 <0.005 <0.005 Iron mg/L 0.01 <0.05 <0.05 Mercury mg/L 0.0001 <0.0001 <0.0001 Total metals Aluminium mg/L 0.01 0.04 0.04 Arsenic mg/L 0.001 <0.001 <0.001 Cadmium mg/L 0.0001 <0.0001 <0.0001 Chromium mg/L 0.001 0.004 <0.001 Copper mg/L 0.001 <0.001 <0.001 Lead mg/L 0.001 <0.001 <0.001 Nickel mg/L 0.001 <0.001 <0.001 Selenium mg/L 0.01 <0.01 <0.01 Zinc mg/L 0.005 <0.005 <0.005 Iron mg/L 0.01 0.13 0.07 Mercury mg/L 0.0001 <0.0001 <0.0001 Nutrients Ammonia as N mg/L 0.01 0.1 0.11 NOx as N mg/L 0.01 0.16 0.16 TKN as N mg/L 0.1 0.7 0.6 TN as N mg/L 0.1 0.9 0.8 TP as P mg/L 0.01 0.04 0.03 RP as P mg/L 0.01 <0.01 <0.01 Other DOC mg/L 1 10 9 Chlorophyll a mg/L 0.001 0.004 -


Appendix C – Assessments of Significance EPBC Act Assessments of Significance

Assessment of significance – Murray cod (Maccullochella peelii peelii) – Vulnerable species An ‘important population’ of a vulnerable species is defined by DotE (2013) as ‘…a population that is necessary for the species’ long-term survival and recovery. This may include populations identified as such in recovery plans, and/or that are: Key source populations either for breeding or dispersal Populations that are necessary for maintaining genetic diversity, and/or Populations that are near the limit of the species’ range’. According to the DotE (2013) ‘significant impact criteria’ for a vulnerable species, an action is likely to have a significant impact on an vulnerable species if there is a real chance or possibility that it will: Lead to a long-term decrease in the size of an important population The proposed action is not located within an important population of Murray Cod (Commonwealth of Australia, 2016) however it is identified as a population under threat. DPI Fisheries sampled fish communities as part of a Short-term intervention monitoring of a fish community response to an environmental flow in the mid and lower Macquarie River: 2014/15 water year (DPI, 2016). This involved sampling in four spatially, geomorphologically and hydrologically different zones at a landscape scale: Zone 1: Macquarie River Burrendong Dam to Dubbo – about a 100 kilometre long stretch

of river. Zone 2: Macquarie River Gin Gin to Warren – about a 100 kilometre long stretch of river

upstream of the Macquarie Marshes. The majority of Zone 2 is upstream of the Warren Weir and included sampling between the Warren Weir and Gin Gin Weir


Zone 4: Lower Macquarie River (below the Macquarie Marshes). This is about a 100 kilometre long stretch of the river between Bells Bridge and the Barwon River confluence. Sampling was not undertaken at some sites in Zone 4 during two of the three sampling events because the river was dry.

DPI Fisheries recorded the highest abundances of Murray Cod in Zone 2. The proposal would benefit Murray Cod by retaining water in the section of the river where the highest abundances of this species were recorded. This would provide refuge habitat so the species can persist and recover once flows return to watercourses further downstream. Reduce the area of occupancy of the species The proposal is unlikely to lead to the long term reduction in the area of occupancy of Murray Cod as it would maintain water in and delay a cease to flow event in the section of the Macquarie River upstream of Warren Weir where DPI Fisheries recorded the highest abundances of Murray Cod. This would assist to maintain the presence of the species in the river system so it can recolonise and disperse throughout the river system following a return to higher flow conditions. Fragment an existing important population into two or more populations The proposal is not located within a listed important population of Murray Cod and would not fragment a listed important population into two or more populations. Due to variable flows in the Macquarie River temporary habitat fragmentation occurs naturally in the system. Adversely affect habitat critical to the survival of a species As the proposal is not located within a listed important population of Murray Cod it is unlikely that the habitat affected is likely to be critical to the survival of the species. Disrupt the breeding cycle of an important population The proposed action is not located within a listed important population of Murray Cod. The proposal is unlikely to disrupt the breeding cycle of the Murray Cod any more than would occur under the do-nothing scenario.


Assessment of significance – Murray cod (Maccullochella peelii peelii) – Vulnerable species Modify, destroy, remove, isolate or decrease the availability or quality of habitat to the extent that the species is likely to decline The proposal will decrease habitat availability within Burrendong Dam, but would prolong the duration that habitat for Murray Cod is available in the main channel of the Macquarie River downstream of the dam. By maintaining flow in Macquarie River downstream of the dam the proposal is likely to assist the species to persist during the current severe drought. Result in invasive species that are harmful to a vulnerable species becoming established in the vulnerable species’ habitat The proposal is unlikely to result in further establishment of invasive species. A Fish Monitoring Plan will be implemented by DPIF in key pools of the Macquarie River and this will enable action to be taken to manage invasive species such as European Carp and Mosquitofish if required. Introduce disease that may cause the species to decline The proposal is unlikely to introduce disease that may cause the species to decline. Interfere with the recovery of the species The proposal would not interfere with the recovery of the species in the context of the current drought. The aim of the proposal is to retain water within the Macquarie River downstream of Burrendong Dam, which includes the section of the river where DPI Fisheries recorded the highest abundance of Murray Cod. Maintaining flow in this section of the Macquarie River is likely to enhance the ability of the species to persist during the current drought conditions and recover in the event that sufficient flows return to the system. Conclusion The impact of the proposal on the Murray Cod is unlikely to be significant because: The proposal will not result in an impact that is otherwise not predicted to occur in the

short term. The proposal would retain water in the section of the Macquarie River where DPI Fisheries

recorded the greatest abundance of Murray Cod. This would provide refuge habitat and enable Murray Cod to recolonise downstream areas when higher flows return.

All reasonable and feasible management measures will be implemented to minimise potential impacts. This will include a Water Quality Monitoring Plan and Fish Monitoring Plan (developed by DPI-F) developed in consultation with relevant government agencies, such as the DPIE-W, DPIF and DPIE. Compared to the do-nothing scenario, the proposal will reduce habitat availability in Burrendong Dam, though will maintain a larger section of better quality fish habitat within Macquarie River downstream of the dam.

Assessment of significance – Silver Perch (Bidyanus bidyanus) – Critically endangered species According to the DotE (2013) ‘significant impact criteria’ for a vulnerable species, an action is likely to have a significant impact on an vulnerable species if there is a real chance or possibility that it will: Lead to a long-term decrease in the size of an important population The proposal would benefit Silver Perch by retaining water in the section of the river where the species was recorded by DPI. Reduce the area of occupancy of the species The proposal will retain water in the main channel of the Macquarie River upstream of the Warren Weir and delay a cease to flow event occurring in the approximately 180 kilometre long section of the Macquarie River between Burrendong Dam and Warren. This will prolong the duration that flow is maintained in this section of the river and that refuge habitat is available for aquatic species, including threatened fish. Monitoring undertaken by DPI Fisheries (2016) recorded Silver Perch in the survey Zone 2 (Gin Gin to Warren). In general, this study concluded that native fish species richness was significantly lower within, and


Assessment of significance – Silver Perch (Bidyanus bidyanus) – Critically endangered species downstream of, the Macquarie Marshes compared with sites sampled upstream. The overall condition of the fish community within the Macquarie River declined along a downstream gradient from ‘poor’ below Burrendong Dam to ‘extremely poor’ in the Macquarie Marshes and downstream to the Barwon River confluence. The proposal is unlikely to result or lead to the long term reduction in the area of occupancy of Silver Perch. Fragment an existing important population into two or more populations Habitat fragmentation occurs naturally in the Macquarie River catchment. The proposal is unlikely to result in additional fragmentation impacts compared to those that would occur under the do-nothing scenario. The proposal would maintain water in the section of the Macquarie River upstream of Warren where there is more favourable habitat for the Silver Perch and where DPI recorded the species (DPI 2016). A Fish Monitoring Plan will be implemented by DPI Fisheries in key pools downstream of Burrendong Dam and this will enable action to be taken should water levels or quality cause distress to fish species within refugpia. Adversely affect habitat critical to the survival of a species The proposal would retain water in the main channel of the Macquarie River upstream of the Warren Weir and delay a cease to flow event occurring in the approximately 180 kilometre long section of the Macquarie River between Burrendong Dam and Warren. This would prolong the duration that flow is maintained in the main channel and that refuge habitat is provided for Silver Perch. This would enhance the likelihood of fish persisting in the system during the drought. Disrupt the breeding cycle of an important population The proposal is unlikely to disrupt the breeding cycle of Silver Perch any more than would occur under the do-nothing scenario. Modify, destroy, remove, isolate or decrease the availability or quality of habitat to the extent that the species is likely to decline By retaining water in a section of the Macquarie River that provides refuge habitat, the proposal is likely to assist the species to persist during the current severe drought. Result in invasive species that are harmful to a vulnerable species becoming established in the vulnerable species’ habitat The proposal is unlikely to result in further establishment of invasive species. A Fish Monitoring Plan will be implemented by DPIF in key pools of the Macquarie River and this will enable action to be taken to manage invasive species such as European Carp and Mosquitofish if required. Introduce disease that may cause the species to decline The proposal is unlikely to introduce disease that may cause the species to decline. Interfere with the recovery of the species The proposal would conserve refuge habitat for the Silver Perch and enhance the ability of the species to persist during the current drought conditions and recover in the event that sufficient flows return to the system. Conclusion The impact of the proposal on Silver Perch is unlikely to be significant because: The proposal will not result in an impact that is otherwise not predicted to occur in the


recorded the presence of Silver Perch. This would provide refuge habitat and enable Silver Perch to recolonise downstream areas when higher flows return.



Assessment of significance – Trout Cod (Macculllochella macquarensis) Endangered species According to the DotE (2013) ‘significant impact criteria’ for a vulnerable species, an action is likely to have a significant impact on an vulnerable species if there is a real chance or possibility that it will: Lead to a long-term decrease in the size of an important population This species has suffered catastrophic decline in both range and abundance, with only one natural population remaining. Historic Trout Cod records are present within the Lower Macquarie River and stocked population are present near Dubbo and a further population is maintained above Burrendong Dam. DPI (2016) recorded one Trout Cod In the reach of the Macquarie River between Burrendong Dam and Dubbo. The proposal would benefit Trout Cod by delaying a cease to flow event in this section of the river. This would provide habitat so the species can persist at its recently recorded location until flows return. Reduce the area of occupancy of the species The proposal is unlikely to lead to the long term reduction in the area of occupancy of the Trout Cod as it would maintain water in the river below Burrendong Dam and delay a cease to flow event in the section of the river where DPI Fisheries recorded this species. This would assist to maintain the presence of the species in the river system so it can recolonise following a return to higher flow conditions. Fragment an existing important population into two or more populations The proposal is unlikely to result in additional fragmentation impacts compared to those that would occur iunder the do-nothing scenario. The proposal would maintain water in the main channel of the Macquarie River between Burrendong Dam and Warren where there is more favourable habitat for the Trout Cod, and where DPI recorded the species (DPI 2016). A fish monitoring plan would be implemented to minimise potential impacts. Adversely affect habitat critical to the survival of a species It is unlikely that the habitat affected is critical to the survival of Trout Cod. Disrupt the breeding cycle of an important population Trout Cod breeding occurs in spring and early summer when the water temperature is around 15 °C. As the proposal will maintain flows downstream of Burrendong Dam it is likely that water temperatures in this reach will be more stable, so no disruption of the Trout Cod breeding cycle is expected. Modify, destroy, remove, isolate or decrease the availability or quality of habitat to the extent that the species is likely to decline By retaining water in a section of the Macquarie River that provides refuge habitat, the proposal is likely to assist the species to persist during the current severe drought. Result in invasive species that are harmful to a vulnerable species becoming established in the vulnerable species’ habitat The proposal is unlikely to result in further establishment of invasive species. A Fish Monitoring Plan will be implemented by DPIF in key pools of the Macquarie River and this will enable action to be taken to manage invasive species such as European Carp and Mosquitofish if required. Introduce disease that may cause the species to decline The proposal is unlikely to introduce disease that may cause the species to decline. Interfere with the recovery of the species The proposal would conserve refuge habitat for the Trout Cod and enhance the ability of the species to persist during the current drought conditions and recover in the event that sufficient flows return to the system. Conclusion The impact of the proposal on Trout Cod is unlikely to be significant because: The proposal will not result in an impact that is otherwise not predicted to occur in the


recorded the presence of Trout Cod. This would provide refuge habitat and enable Trout Cod to recolonise downstream areas when higher flows return.

All reasonable and feasible management measures will be implemented to minimise potential impacts. This will include a Water Quality Monitoring Plan and Fish Monitoring Plan


Assessment of significance – Trout Cod (Macculllochella macquarensis) Endangered species (developed by DPI-F) developed in consultation with relevant government agencies, such as the DPIE-W, DPIF and DPIE. Compared to the do-nothing scenario, the proposal will reduce habitat availability in Burrendong Dam, though will maintain a larger section of better quality fish habitat within Macquarie River downstream of the dam.


FM Act Assessments of Significance

Assessment of significance – Eel-tailed Catfish (Tandanus tansanus) Endangered population The Eel Tailed Catfish (Tandanus tandanus) is a non-migratory, benthic (bottom dwelling) species. It is relatively sedentary and adults typically only move within a 5 km range (DPI 2015). The western population was once highly abundant and widespread throughout the Murray Darling River System in NSW, however, in NSW most riverine populations have declined significantly since the 1970s, and the species is no longer common in many areas where it was formally abundant (DPI 2015). Eel Tailed Catfish are listed as an Endangered Population under FM Act. a) in the case of a threatened species, whether the action proposed is likely to have an adverse effect on the life cycle of the species such that a viable local population of the species is likely to be placed at risk of extinction Not applicable b) in the case of an endangered population, whether the action proposed is likely to have an adverse effect on the life cycle of the species that constitutes the endangered population such that a viable local population of the species is likely to be placed at risk of extinction The proposal would prolong the duration that habitat for Eel Tailed Catfish is available in the main channel of the Macquarie River downstream of Burrendong Dam. By retaining water in sections of the Macquarie River that provides refuge habitat, the proposal is likely to assist the species to persist during the current severe drought. This would assist to maintain the presence of the species in the river system so it can recolonise and disperse following a return to higher flow conditions. (c) in the case of an endangered ecological community or critically endangered ecological community, whether the action proposed: i) is likely to have an adverse effect on the extent of the ecological community such that its local occurrence is likely to be placed Not applicable (ii) is likely to substantially and adversely modify the composition of the ecological community such that its local occurrence is likely to be placed at risk of extinction Not applicable d) in relation to the habitat of a threatened species, population or ecological community: (i) the extent to which habitat is likely to be removed or modified as a result of the action proposed, and The proposal will retain water in the main channel of the Macquarie River upstream of the Warren Weir and delay a cease to flow event occurring in the main channel of the Macquarie River between Burrendong Dam and Warren. This will prolong the duration that flow is maintained upstream of Warren and that refuge habitat is provided for aquatic species, including Eel Tailed Catfish.

While the proposal will reduce habitat availability in Burrendong Dam it is predicted that the proposal will have benefits to water quality and aquatic ecology in the dam that would not be observed under the do-nothing scenario.

ii) whether an area of habitat is likely to become fragmented or isolated from other areas of habitat as a result of the proposed action, and The proposal is unlikely to change the effects of fragmentation that would occur under the do-nothing scenario. The proposal would maintain water in the main channel of the Macquarie River upstream of Warren which is where DPI recorded the species (DPI 2016).

(iii) the importance of the habitat to be removed, modified, fragmented or isolated to the long-term survival of the species, population or ecological community in the locality The proposal is unlikely to remove, modify, fragment or isolate habitat important for the long term survival of Eel-tailed Catfish. (e) whether the action proposed is likely to have an adverse effect on critical habitat (either directly or indirectly) The proposal would maintain refuge habitat for this species in the Macquarie River to assist it to persist during the drought and allow for recovery once higher flows return. (f) whether the action proposed is consistent with the objectives or actions of a recovery plan or threat abatement plan


Assessment of significance – Eel-tailed Catfish (Tandanus tansanus) Endangered population A recovery plan has not been developed for the Eel Tailed Catfish. The proposal would maintain refuge habitat for this species in the Macquarie River to assist it to persist during the drought and allow for recovery once higher flows return. g) whether the action proposed constitutes or is part of a key threatening process or is likely to result in the operation of, or increase the impact of, a key threatening process The proposed action constitutes as part of the key threatening process, "Installation and operation of instream structures and other mechanisms that alter natural flow regimes of rivers and streams." The proposed action is unlikely to cause a significant increase in the impact of this key threatening process because it would be undertaken in a severe drought and the Water Sharing Plan has been suspended such that there is no allocation for environmental water deliveries. Conclusion The impact of the proposal on Eel-tailed Catfish is unlikely to be significant because: The proposal will not result in an impact that is otherwise not predicted to occur in the


recorded the presence of Eel-tailed Catfish. This would provide refuge habitat and enable Eel-tailed Catfish to recolonise downstream areas when higher flows return.


Assessment of significance – Trout Cod (Macculllochella macquarensis) Endangered species Trout Cod (Maccullochella macquariensis) is a moderately large predatory freshwater fish endemic to the Murray- Darling River system (DSE 2008). The Trout Cod is listed as an endangered species under both NSW and Commonwealth legislation. This species has suffered catastrophic decline in both range and abundance, with only one natural population remaining (DSE 2008). Historic Trout Cod records are present within the Lower Macquarie with populations supported by breeding programs near Dubbo and above Burrendong Dam. a) in the case of a threatened species, whether the action proposed is likely to have an adverse effect on the life cycle of the species such that a viable local population of the species is likely to be placed at risk of extinction The proposal would benefit Trout Cod by delaying a cease to flow event between Burrendong Dam and Warren which includes habitat for the stocked population near Dubbo and is the section of the river where this species were recorded by DPI in 2016. b) in the case of an endangered population, whether the action proposed is likely to have an adverse effect on the life cycle of the species that constitutes the endangered population such that a viable local population of the species is likely to be placed at risk of extinction Not applicable (c) in the case of an endangered ecological community or critically endangered ecological community, whether the action proposed: i) is likely to have an adverse effect on the extent of the ecological community such that its local occurrence is likely to be placed Not applicable (ii) is likely to substantially and adversely modify the composition of the ecological community such that its local occurrence is likely to be placed at risk of extinction Not applicable d) in relation to the habitat of a threatened species, population or ecological community: (i) the extent to which habitat is likely to be removed or modified as a result of the action proposed, and


Assessment of significance – Trout Cod (Macculllochella macquarensis) Endangered species The proposal will retain water in the main channel of the Macquarie River upstream of the Warren Weir and delay a cease to flow event occurring in the 180 kilometre long section of the Macquarie River between Burrendong Dam and Warren which includes a stocked population of Trout Cod near Dubbo. This will prolong the duration that flow is maintained in this section of the river and that refuge habitat is provided for aquatic species, including Trout Cod. While the proposal will reduce habitat availability in Burrendong Dam it is predicted that the proposal will have benefits to water quality and aquatic ecology in the dam that would not be observed under the do-nothing scenario. ii) whether an area of habitat is likely to become fragmented or isolated from other areas of habitat as a result of the proposed action, and The proposal is unlikely to result in additional fragmentation impacts compared to those that would occur under the do-nothing scenario. The proposal would maintain water in the main channel of the Macquarie River between Burrendong Dam and Warren where there is more favourable habitat for the Trout Cod, and there is a known stocked population near Dubbo. A fish monitoring plan would be implemented to enable actions to be implemented if fish are stressed due to water quality or quantity impacts. (iii) the importance of the habitat to be removed, modified, fragmented or isolated to the long-term survival of the species, population or ecological community in the locality The proposal is unlikely to remove, modify, fragment or isolate habitat important for the long term survival of Trout Cod. (e) whether the action proposed is likely to have an adverse effect on critical habitat (either directly or indirectly) The proposal would maintain refuge habitat for this species in the Macquarie River to assist it to persist during the drought and allow for recovery once higher flows return. (f) whether the action proposed is consistent with the objectives or actions of a recovery plan or threat abatement plan The proposal is consistent with the objectives of the Trout Cod recovery plan (DPI 2006), as it will maintain aquatic habitat in Macquarie River downstream of Burrendong Dam. g) whether the action proposed constitutes or is part of a key threatening process or is likely to result in the operation of, or increase the impact of, a key threatening process The proposed action constitutes as part of the key threatening process, "Installation and operation of instream structures and other mechanisms that alter natural flow regimes of rivers and streams." The proposed action is unlikely to cause a significant increase in the impact of this key threatening process because it would be undertaken in a severe drought and the Water Sharing Plan has been suspended such that there is no allocation for environmental water deliveries. Conclusion The impact of the proposal on Trout Cod is unlikely to be significant because: The proposal will not result in an impact that is otherwise not predicted to occur in the


recorded the presence of Trout Cod. This would provide refuge habitat and enable Trout Cod to recolonise downstream areas when higher flows return.



Assessment of significance – Silver Perch (Bidyanus bidyanus) Vulnerable species Silver Perch (Bidyanus bidyanus) are endemic to the Murray-Darling River system (TSSC 2013). Silver Perch are listed as Critically Endangered under the EPBC Act and as Vulnerable under the FM Act. Silver Perch are found in a wide range of habitats and climates across the Murray-Darling Basin. They are generally found in faster-flowing water including rapids and runs and more open sections of river. They sometimes form large shoals in open water. a) in the case of a threatened species, whether the action proposed is likely to have an adverse effect on the life cycle of the species such that a viable local population of the species is likely to be placed at risk of extinction The proposal would benefit Silver Perch by delaying a cease to flow event between Burrendong Dam and Warren which is the section of the river where this species was recorded by DPI in 2016. b) in the case of an endangered population, whether the action proposed is likely to have an adverse effect on the life cycle of the species that constitutes the endangered population such that a viable local population of the species is likely to be placed at risk of extinction Not applicable (c) in the case of an endangered ecological community or critically endangered ecological community, whether the action proposed: i) is likely to have an adverse effect on the extent of the ecological community such that its local occurrence is likely to be placed Not applicable (ii) is likely to substantially and adversely modify the composition of the ecological community such that its local occurrence is likely to be placed at risk of extinction Not applicable d) in relation to the habitat of a threatened species, population or ecological community: (i) the extent to which habitat is likely to be removed or modified as a result of the action proposed, and The proposal will prolong the duration that flow is maintained upstream of Warren and that refuge habitat is provided for aquatic species, including Silver Perch. While the proposal will reduce habitat availability in Burrendong Dam it is predicted that the proposal will have benefits to water quality and aquatic ecology in the dam that would not be observed under the do-nothing scenario. ii) whether an area of habitat is likely to become fragmented or isolated from other areas of habitat as a result of the proposed action, and The proposal is unlikely to result in additional fragmentation impacts compared to those that would occur under the do-nothing scenario. The proposal would maintain water in the section of the Macquarie River between Burrendong Dam and Warren where there is more favourable habitat for the Silver Perch and DPI recorded the species (DPI 2016).

(iii) the importance of the habitat to be removed, modified, fragmented or isolated to the long-term survival of the species, population or ecological community in the locality The proposal is unlikely to remove, modify, fragment or isolate habitat important for the long term survival of Silver Perch. (e) whether the action proposed is likely to have an adverse effect on critical habitat (either directly or indirectly) The proposal would maintain refuge habitat for this species in the Macquarie River to assist it to persist during the drought and allow for recovery once higher flows return. (f) whether the action proposed is consistent with the objectives or actions of a recovery plan or threat abatement plan A recovery plan has not been developed for the Silver Perch. The proposal would maintain refuge habitat for this species in the Macquarie River to assist it to persist during the drought and allow for recovery once higher flows return. g) whether the action proposed constitutes or is part of a key threatening process or is likely to result in the operation of, or increase the impact of, a key threatening process


Assessment of significance – Silver Perch (Bidyanus bidyanus) Vulnerable species The proposed action constitutes as part of the key threatening process, "Installation and operation of instream structures and other mechanisms that alter natural flow regimes of rivers and streams." The proposed action is unlikely to cause a significant increase in the impact of this key threatening process because it would be undertaken in a severe drought and the Water Sharing Plan has been suspended such that there is no allocation for environmental water deliveries. Conclusion The impact of the proposal on Silver Perch is unlikely to be significant because: The proposal will not result in an impact that is otherwise not predicted to occur in the


recorded the presence of Silver Perch. This would provide refuge habitat and enable Silver Perch to recolonise downstream areas when higher flows return.

All reasonable and feasible management measures will be implemented to minimise potential impacts. This will include a Water Quality Monitoring Plan and Fish Monitoring Plan (developed by DPI-F) developed in consultation with relevant government agencies, such as the DPIE-W, DPIF and DPIE. Compared to the do-nothing scenario, the proposal will reduce habitat availability in Burrendong Dam, though will maintain a larger area of better quality fish habitat within Macquarie River downstream of the dam.

GHD 270 Summer Street ORANGE NSW 2800 T: 61 2 6393 6400 F: 61 2 6393 6401 E: [email protected]

© GHD 2019 This document is and shall remain the property of GHD. The document may only be used for the purpose for which it was commissioned and in accordance with the Terms of Engagement for the commission. Unauthorised use of this document in any form whatsoever is prohibited. 12512398-94038/https://projectsportal.ghd.com/sites/pp01_02/burrendongdeepwaters/ProjectDocs/12512398-REP-Water Quality and Aquatic Ecology Impact Assessment.docx Document Status

Revision Author Reviewer Approved for Issue Name Signature Name Signature Date

0 J. Cairns P. Carson D. Mees 29/10/2019

1 J. Cairns P. Carson D. Mees 13/11/2019

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Appendix E – Threatened biodiversity assessment Databases Searched

NSW Office of Environment and Heritage (OEH) BioNet Atlas for records of threatened biota previously recorded in the locality (website for the Atlas of NSW Wildlife) (OEH 2019a).

Department of the Environment and Energy (DoEE) Protected Matters Search Tool for biota listed under the EPBC Act that are known or predicted to occur in the locality (DoEE 2019a).

Likelihood of occurrence

Matters considered in determining the likelihood of occurrence include:

Known natural distributions including records (database searches)

Specific habitat requirements

Home range size and habitat dependence

Topographical preferences

Geological preference

The likelihood of occurrence scale is defined as follows:

Scale Description Known Species known to occur within the site. High Presence of high value suitable habitat (e.g. breeding and foraging habitat; important

movement corridors). Moderate Presence of medium value suitable habitat (e.g. disturbed breeding conditions;

constrained foraging habitat; movement corridors). Low Presence of low value suitable habitat (e.g. disturbed conditions; isolated small habitat

area; fragmented movement corridors). None No suitable habitat or corridors linking suitable habitat present.

Threatened Species assessment table

Table F-1 Plant community types within close proximity to the proposal site (2 km)

PCT BC Act Status EPBC Act Status 511- Queensland Bluegrass - Redleg Grass - Rats Tail Grass - spear grass - panic grass derived grassland of the Nandewar Bioregion and Brigalow Belt South Bioregion

White Box Yellow Box Blakely’s Red Gum Woodland EEC

Critically Endangered- White Box-Yellow Box-Blakely's Red Gum Grassy Woodland and Derived Native Grassland

461- Tumbledown Gum woodland on hills in the northern NSW South Western Slopes Bioregion and southern Brigalow Belt South Bioregion

Not listed Not listed

266- White Box grassy woodland in the upper slopes sub-region of the NSW South Western Slopes Bioregion



78- River Red Gum riparian tall woodland / open forest wetland in the Nandewar Bioregion and Brigalow Belt South Bioregion



PCT BC Act Status EPBC Act Status 796- Derived grassland of the NSW South Western Slopes



332- Tumbledown Red Gum - Black Cypress Pine - Red Stringybark woodland on rocky hills in the NSW central western slopes


185- Dwyers Red Gum - White Cypress Pine - Currawang shrubby woodland mainly in the NSW South Western Slopes Bioregion


277- Blakelys Red Gum - Yellow Box grassy tall woodland of the NSW South Western Slopes Bioregion



76- Western Grey Box tall grassy woodland on alluvial loam and clay soils in the NSW South Western Slopes and Riverina Bioregions

Inland Grey Box Woodland in the Riverina, NSW South Western Slopes, Cobar Peneplain, Nandewar and Brigalow Belt South Bioregions EEC

Endangered- Grey Box (Eucalyptus microcarpa) Grassy Woodlands and Derived Native Grasslands of South-eastern Australia

272- White Box - Black Cypress Pine - red gum +/- Mugga Ironbark shrubby woodland in hills of the NSW central western slopes


267- White Box - White Cypress Pine - Western Grey Box shrub/grass/forb woodland in the NSW South Western Slopes Bioregion



GHD | Report for WaterNSW ‐ Burrendong Dam Deep Water Storage Access, 12512398

Appendix F – Aboriginal Due Diligence Assessment and Statement of Heritage Impact Report

This report is not included in this version of the REF as it includes restricted culturally

sensitive information


Appendix G – Construction noise contours

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(A)


Appendix H – DPI Fisheries – response to consultation under section 199 of the Fisheries Management Act 1994

FISHERIES AQUATIC ENVIRONMENT BRANCH www.dpi.nsw.gov.au TAMWORTH AGRICULTURAL INSTITUTE 4 Marsden Park Road Tel: 02 6763 1255 CALALA NSW 2340

OUR REF: C19/641 FE19/972 11th November 2019 Sean Iselin WaterNSW Level 14, 169 Macquarie Street PARRAMATTA, NSW 2150

Dear Mr Iselin

RE: Consultation under s.199 of the Fisheries Management Act 1994 for dredging & reclamation associated with Coffer Dam Construction, Burrendong Dam Deep Water Storage Access Project

Thank you for providing notification on the 30th October 2019, seeking comment on the proposed works from DPI Fisheries, a division of NSW Department of Primary Industries (DPI). The notification complies with s.199(1)(a) of the Fisheries Management Act 1994 (FM Act) concerning the proposed dredging and reclamation activities.

DPI Fisheries is responsible for ensuring that fish stocks are conserved and that there is no net loss of key fish habitats upon which they depend. To achieve this, DPI Fisheries ensures that developments comply with the requirements of the Fisheries Management Act 1994 (namely the aquatic habitat protection and threatened species conservation provisions in Parts 7 and 7A of the Act, respectively), and the associated Policy and Guidelines for Fish Habitat Conservation and Management (2013). In addition, DPI Fisheries is responsible for ensuring the sustainable management of commercial, recreational and Aboriginal cultural fishing, aquaculture, marine parks and aquatic reserves within NSW.

DPI Fisheries has reviewed the proposal in light of those provisions and has no objections to the coffer dam construction work, Burrendong Dam Deep Water Storage Access Project provided that:

1. Environmental safeguards (e.g. sediment fences, booms etc.) are to be installed consistent with “Managing Urban Stormwater: Soils and Construction” (4th Edition Landcom, 2004, aka the Blue Book (see http://www.environment.nsw.gov.au/resources/water/BlueBookVol1.pdf) to ensure that there is no escape of turbid plumes into the adjacent aquatic environment;

2. Any material removed from the waterway that is to be deposited or stockpiled on land is to be located well away from the waterway and to be contained by appropriate sediment control devices as outlined in the Blue Book;

3. A visual inspection of the waterway for dead or distressed fish (indicated by fish gasping at the water surface, fish crowding in pools or at the creek’s banks) is to be undertaken during the works. Observations of dead or distressed fish are to be reported immediately to the District Fisheries Officer at Bathurst (Phone (02) 6331 1428, email [email protected]).

If you require any further information, please do not hesitate to contact me on 6763 1255. Yours sincerely,

David Ward Fisheries Manager (Tamworth)

GHD

Level 3 GHD Tower 24 Honeysuckle Drive Newcastle NSW 2300 PO BOX 5403 Hunter Region Mail Centre NSW 2310 T: 61 2 4979 9999 F: 61 2 4979 9988 E: [email protected]

© GHD 2019

This document is and shall remain the property of GHD. The document may only be used for the purpose for which it was commissioned and in accordance with the Terms of Engagement for the commission. Unauthorised use of this document in any form whatsoever is prohibited. 24DJSZNHUEPC-1850682920-13/https://projectsportal.ghd.com/sites/pp01_02/burrendongdeepwaters/ProjectDocs/12512398-REP-A_Draft REF in preparation issue 20190930 workshop.docx

Document Status

Revision Author Reviewer Approved for Issue Name Signature Name Signature Date

0 A. Bristow P. Carson P. Carson 28/10/2019

1 A. Bristow P. Carson D. Mees 13/11/2019

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Documents

12512398-REP Final Draft REF Burrendong Deep Storage Access · Burrendong Dam Deep Water Storage (referred to as the ‘proposal’) to supply water to communities that rely on surface