The Northern Road Upgrade, Narellan to Bringelly Review of ... · Appendix D Hydraulic results for transverse drainage design 51 ... Bicycle and pedestrian crossing provisions at

Appendix B Hydrology

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MR154 THE NORTHERN ROAD UPGRADE Between The Old Northern Rd & Mersey Rd

DRAINAGE DESIGN REPORT

CONCEPT DESIGN

100% STAGE

Revision C 12 OCTOBER 2012 NB11363-NHY-RP-0077

Concept Drainage Design Report

SINCLAIR KNIGHT MERZ http://dmca.skmconsulting.com/sites/NB11363/DmcaConsult/Deliverables/Reports/Drainage Design Report/100 RevC/NB11363-NHY-RP-0077-Concept_100 RevC.docx PAGE i

Contents 1. Introduction 1

1.1. Project description 1 1.2. Scope of report 3

2. Drainage design objectives and criteria 4 2.1. Transverse drainage design requirements 4 2.2. Drainage design criteria for local road tie-ins 6 2.3. Pavement drainage design requirements 6 2.4. Design assumptions 7

3. Design methodology 9 3.1. Overview 9 3.2. Review of existing data and reports 9

4. Transverse drainage design 11 4.1. Estimation of design flows 11 4.1.1. Definition of catchments 11 4.1.2. Design rainfall intensities 11 4.1.3. Design flows 14 4.1.4. Validation of flows 14 4.1.5. Consideration of development in small catchments 14 4.1.6. Estimation of extreme flood events 14 4.2. Hydraulic analysis and design 15 4.2.1. Calculation method 15 4.2.2. Existing conditions 17 4.2.3. Concept design 17 4.2.4. Environmental considerations 18 4.3. Culvert outlet protection measures 18 4.3.1. Energy dissipators 18 4.3.2. Rock lined transition apron 19 4.4. Open channels 20 4.5. Major creek crossings 22

5. Pavement drainage design 24 5.1. Design overview 24 5.2. Pavement drainage hydrology 24 5.3. Pavement drainage Concept Design 25 5.3.1. Pit locations 25 5.3.2. Pipe sizing 25 5.4. Pavement drainage at road tie-ins 25


SINCLAIR KNIGHT MERZ http://dmca.skmconsulting.com/sites/NB11363/DmcaConsult/Deliverables/Reports/Drainage Design Report/100 RevC/NB11363-NHY-RP-0077-Concept_100 RevC.docx PAGE ii

5.4.1. Existing pipe drainage 26 5.5. Pavement surface flow 26 5.6. Subsurface drainage 27 5.7. Consideration for temporary works 27

6. Impact assessment 29 6.1. Upstream properties 29 6.2. Downstream properties 29 6.3. Existing farm dams 33 6.4. Impacts to regional flooding – Probable Maximum Flood 34

7. Water quality 36 7.1. Construction phase 36 7.1.1. Sediment basin sizing 36 7.1.2. Sediment basin design 38 7.2. Operational phase 40 7.2.1. Potential water quality issues 40 7.2.2. Water quality objectives 41 7.2.3. Proposed water quality controls 41 7.2.3.1. Vegetated swales 41 7.2.3.2. Spill management basins 41 7.2.3.3. Access to spill basins 43

8. Considerations for detailed design 44 9. References 45 Appendix A List of drawings 46 Appendix B Response to review comments 49 Appendix C Catchment areas and design flows 50 Appendix D Hydraulic results for transverse drainage design 51 Appendix E Design of outlet protection works 52 Appendix F Assessment of peak flows 53 Appendix G Aquaplaning checks 54 Appendix H Soil test results 55


SINCLAIR KNIGHT MERZ http://dmca.skmconsulting.com/sites/NB11363/DmcaConsult/Deliverables/Reports/Drainage Design Report/100 RevC/NB11363-NHY-RP-0077-Concept_100 RevC.docx PAGE iii

Document history and status Revision Date issued Reviewed by Approved by Date approved Revision type

A 06/07/12 A.Hillhouse W.Singleton 06/07/12 RMS Review

B 20/9/12 A.Hillhouse W.Singleton 20/9/12 RMS Review

C 12/10/12 A.Hillhouse W.Singleton 12/10/12 Final

Distribution of copies Revision Copy no Quantity Issued to

A 1 2 Nhu Doan + Nick Bartho

B 1 2 Nhu Doan + Nick Bartho

C 1 2 Nhu Doan + Nick Bartho

Printed: 12 October 2012

Last saved: 11 October 2012 03:51 PM

File name: http://dmca.skmconsulting.com/sites/NB11363/DmcaConsult/Deliverables/Reports/Drainage Design Report/100 RevC/NB11363-NHY-RP-0077-Concept_100 RevC.docx

Author: Donna Hughes, Shane Ruscheinsky

Project manager: Warwick Singleton

Name of organisation: Sinclair Knight Merz

Name of project: MR154 The Northern Road Upgrade

Name of document: Drainage Design Report – 100% Concept Design

Document version: Revision C

Project number: NB11363


SINCLAIR KNIGHT MERZ http://dmca.skmconsulting.com/sites/NB11363/DmcaConsult/Deliverables/Reports/Drainage Design Report/100 RevC/NB11363-NHY-RP-0077-Concept_100 RevC.docx PAGE 1

1. Introduction 1.1. Project description

The NSW Roads and Maritime Services (RMS) propose to upgrade 15 km of The Northern Road between The Old Northern Road, Narellan and Mersey Road, Bringelly (the proposal). The proposal would be undertaken within the Camden and Liverpool local government areas (LGAs) in the RMS Sydney region.

An overview of the proposal and the locality has been shown in Figure 1.1.

The proposal includes increasing The Northern Road reservation to accommodate widening from a two-lane undivided road, to a four-lane divided road (twin carriageways separated by a median). The upgrade would allow for an ultimate six-lane configuration through future widening works within the median.

Key features of the proposal include:

Dual carriageways with a central median.

A posted vehicle speed limit of 80 km/h.

Provision for a three metre wide off-road shared pedestrian/cyclist path.

Works at 21 intersections including 13 signalised and 8 un-signalised intersections.

Realignment of side roads to align with intersections.

Two metre wide kerbside shoulders.

Bicycle and pedestrian crossing provisions at traffic lights.

Bus priority capability at traffic lights and indented bus bays on both sides of The Northern Road.

Designated turning lanes at traffic lights.

Temporary u-turn facilities located opposite traffic lights at the upgraded intersections of Lowes Creek Link Road, Belmore Road and Derwent Road.

Construction of a new bridge over Narellan Creek and Thompsons Creek.

Scour protection works at Narellan Creek and Thompsons Creek.

Upgrade of the bridge sized culvert over Lowes Creek.

Existing properties on The Northern Road would continue to have direct left in/left out access until precinct development takes place.

Adjustments to public utilities including gas, electricity and telephone services along the alignment.



Flood immunity for a 100 year average recurrence interval (ARI).

Ancillary construction facilities including temporary construction compound and stockpile sites.

Figure 1.1 – Project location



1.2. Scope of report

This report covers the concept drainage design for the project and includes:

Transverse drainage.

Pavement drainage system.

Water quality treatment measures.

This report should be read in conjunction with following documents:

NB11363-MMD-RP-0072 - Concept Design Report.

NB11363-ECT-RP-0051 - Bridge Concept Options Report which contains model results at major creek crossings.

Drainage design drawings (refer to Appendix A for drawing list).



2. Drainage design objectives and criteria 2.1. Transverse drainage design requirements

RMS’ design criteria for the proposal stipulates that investigations, flood assessment and modelling to confirm and enhance the understanding of flooding within the project catchments must be undertaken during the concept design for the proposed upgrade. Issues to be addressed include:

Ultimate effects of the road on regional flooding for the Probable Maximum Flood (PMF) and details of appropriate flood mitigation measures.

Serviceability effects of afflux on adjacent properties and the stability of the adjacent road embankment up to a 100 year average recurrence interval (ARI) event.

Ultimate limit state of bridges, major drainage structures and major retaining walls – 2000 year ARI event.

Design criteria for transverse drainage include:

Application of the minimum ARIs as shown in Table 2-1.

The drainage works must not exacerbate flooding conditions in private or public land for all storms up to the 100 year ARI, unless through consultation with the RMS the impact of the road works is considered to be acceptable.

All outlets of the drainage system must incorporate energy dissipation, erosion and sediment control.

The tops of pipes and box culverts are to be a minimum 300mm below the underside of the bottom of the selected material zone.

Transverse drainage must be sized to take into account the potential effect of future climate change.

A 50% blockage factor is to be applied to the inlets of transverse drainage culverts and/or pipes with headwalls.



Table 2-1 – Minimum ARIs for transverse drainage design

Item Minimum ARI

Culverts where surcharge is allowable 100 year Structures where surcharge is undesirable 100 year Major storm event check for no property damage (including adverse impacts) 100 year

Major storm event check for no structural damage 2000 year Check for no unacceptable impacts on private or public property

All storms up to the 100 year

Further details of project specific design criteria are provided below:

Consideration of climate change is to be in accordance with the “Practical Consideration of Climate Change, Floodplain Risk Management Guideline” (DECC, 2007). This guideline provides a range of predicted climate change impacts for various regions. Within the Sydney Metropolitan region the predicted range for rainfall increase up to the year 2070 is between -7 and +10%. A conservative 10% increase to design rainfall intensities has been applied for Concept Design.

As per the recent RMS Camden Valley Way project, a 50% blockage factor will be applied at culvert inlets through the assumption that the lower half of culvert inlet is blocked. Circular culverts will be analysed through the adoption of a higher invert level and a diameter that provides an equivalent flow area of half the full flow area. Transverse culverts are designed so that catchment runoff is fully conveyed through culverts without inundation of the road or bypass flow into an adjacent catchment.

It is given that land adjacent The Northern Road will be developed for residential, commercial or industrial use at some point in the future and would require stormwater detention measures in accordance with local Council requirements. For the concept design of transverse drainage structures it is assumed that 100 year ARI peak flows would be maintained at pre-developed levels for large catchment areas greater than 10 hectares, as development of these larger areas would typically include regional detention basins. For smaller catchment areas less than 10 hectares, transverse drainage is designed for peak flows assuming future development without detention measures.

The minimum level on the road used for design of transverse drainage is the lowest kerb invert. This was used as the pavement drainage design may discharge to the upstream side of the road potentially causing ponded water at the transverse drainage culvert to back up pipes onto the roadway.

For events up to the 100 year ARI, the aim of the concept design is to have no increase in existing water levels at the upstream property boundary (for un-blocked conditions). This



conservative afflux objective is proposed in recognition of the sensitivity of the existing and proposed developments within the upstream catchments.

The cross drainage design has assumed existing farm dams will be retained unless subject to conditions presented in Section 6.3. Pavement drainage is not directed into existing farms dams.

The minimum cover to the top of drainage structures from finished road level is taken to be 1.1m (300mm cover from top of drainage structure to underside of the select material plus 800mm for the road pavement).

Any impacts to flood levels or flow distribution at The Northern Road where development is currently underway (e.g. Oran Park) is not accounted for in the concept drainage design.

The design criteria does not require a freeboard for the design event, however when culverts are not blocked freeboard is available. An assessment of pipe class has not been undertaken during the concept design as this would be undertaken as part of the development of the detailed design.

Existing dams are to be maintained where possible and where the proposed drainage works impact on the dams marginally, dam walls and spillways would be reconstructed to suit. Where more than half the dam is impacted, the dam would be filled and roadworks and associated drainage will be constructed on top of it. Details are provided in Section 6.3.

2.2. Drainage design criteria for local road tie-ins

Drainage works for tie-ins to local roads within Local Government Authority (LGA) boundaries have been designed to satisfy the RMS design criteria for The Northern Road, which is either consistent with LGA specifications or requires a higher level of performance. Liverpool Council notes open channels are to be designed to convey the major event, which for this road upgrade is the 100 year ARI event. This criteria has been adopted where channels are provided through private properties.

An exception to the above is the Camden Council design criteria that specifies freeboard to roads at waterway crossings. The design of tie-ins is generally limited to a short section of the local road and there is limited scope to raise the road or provide for the freeboard requirement. It is assumed that future local road upgrades associated with catchment development will upgrade local roads and drainage to fully address Camden Council requirements including freeboard.

2.3. Pavement drainage design requirements

Pavement drainage is to be designed for the 20 year ARI event with the 100 year ARI event assessed to ensure that at least one lane in each direction is not inundated and available for traffic passage. The stormwater drainage system must be designed to pick up all pavement water



(including drainage layers). The design must prevent concentrations of water and long surface flow paths on the pavement in super-elevation areas.

The design criteria shown in Table 2-2 have been used in the development of the pavement drainage design.

Table 2-2 – Design criteria for pavement drainage design

Item Criteria

Piped system (including pits) 20 year ARI design Max. velocity in RCP 8.0 m/s Minimum size

Pipes crossing the pavement - 450mm Dia Pipes not crossing the pavement - 375mm Dia

Maximum spacing between pits 120 metres (ARR Section 1.5.2) Minimum grade 0.5%, To be self cleaning in a 6 month ARI storm event. Pit depths Provide for connection of subsoil drainage. Self cleansing velocity 0.6 m/s in 6 month ARI

Blockage design at inlet pits 20% on grade pit and 50% sag pits

Minimum freeboard at pit 150 mm in design ARI

Maximum gutter flow width No intrusion of flow into travel lane in design ARI (2.0 m for SA gutter)

Channels and open drains 5 year ARI design Gross pollutant traps 1 year ARI design Cycleways 1 year ARI design Runoff from ramps or turning roadways 2 year ARI design

2.4. Design assumptions

Assumptions made during the development of the concept design are provided below. Further assumptions, particular to specific design aspects, are detailed in corresponding sections of the report.

To ensure that all drainage elements have the required design life it has been assumed that no existing transverse drainage will be retained. All existing transverse drainage culverts would be removed and replaced with new culverts. Further investigation into retaining existing transverse culverts, such as the culverts at Narellan Creek, would be undertaken during detailed design.

Design details for fish passage at box culverts will be undertaken during the development of the detailed design for The Northern Road.



The concept design of transverse drainage at some locations has adopted drop inlet pits to provide cover to pipes. The selection and sizing of pits are not included in the concept design. It is assumed this would be undertaken during detailed design of the upgrade.

Inundation within private properties is reduced or maintained at the current level, thus floor level survey is not required.

Hydraulic models were not calibrated using observed data, thus model parameters were assumed from recommendations in literature and experience in similar catchments.

The development of the concept design has identified instances where adverse flow conditions require work to be undertaken in private properties or downstream of local roads. Works have been sized for the 100 year ARI event such that afflux in the water courses upstream and downstream of the culverts would not result in adverse impacts to adjacent properties. The design of these works would be subject to consultation with landholders and local councils during detailed design.



3. Design methodology 3.1. Overview

Tasks that were undertaken during the development of the concept drainage design include:

Review of existing data and reports.

Estimation of design flows for transverse drainage.

Hydraulic assessment of the existing transverse drainage capacity.

Concept design for transverse drainage.

Concept design for pavement drainage.

Concept design for energy dissipators and outlet protection works.

Hydraulic modelling of major crossings using HEC-RAS - Narellan Creek, Lowes Creek and Thompson’s Creek crossings.

Assessment of impacts to adjacent properties and associated mitigation works.

Concept design for construction phase and operational water quality control measures.

3.2. Review of existing data and reports

Initial Assessment of Drainage Requirements, The Northern Road Upgrade: Camden Valley Way to Mersey Road (LACE, 2011)

RMS engaged Lyall and Associates Consulting Engineers (LACE) to undertake a preliminary drainage investigation for The Northern Road upgrade. This included:

Assessment of contributing catchments.

Estimation of design flows.

Assessment of existing drainage capacity.

HEC-RAS modelling at selected low points.

Preliminary design for transverse drainage.

Assessment of the change in flow discharging at existing low points due to the change in catchment areas and increased imperviousness associated with the widening of the road.

SKM reviewed the report and HEC-RAS models provided by LACE. Hydrologic analysis undertaken for concept design resulted in minor differences to some contributing catchments. These differences were due to the interpretation of contours or changes between the preliminary and concept road designs. For example, in some locations the carriageway is split resulting in some



run-off being directed into an adjacent catchment and/or partially into the pavement drainage system.

This report referenced design flows and flood levels for Narellan Creek from the Upper Nepean River Tributary Flood Studies Volume 2 – Stage 3 (LMCE, 1999).

Upper South Creek Flood Study 2011

The Upper South Creek Flood Study was adopted by Camden Council in Novemeber 2011. The flood study provides design flood levels for a number of major drainage lines crossing The Northern Road south of Bringelly Road, such as Lowes Creek. The flood study will need to be reviewed and considerd in the detailed design of the upgrade in consultation with Camden Council.

Design for development in adjacent areas – Harrington Grove and Oran Park

The designs for residential release areas in Oran Park and Harrington Grove are currently being prepared by Brown Consulting. These design works include both transverse and pavement drainage designs for The Northern Road. As part of the Oran Park development, Brown Consulting has prepared the permanent road design between 3350 and 3800 for construction in 2013 that will tie into the existing Northern Road. Browns have also designed the tie-ins between their permanent design and the SKM’s Northern Road Upgrade design. This design ties-in with The Northern Road upgrade design at 2980 in the south and 4600 in the north. Brown Consulting have also prepared the transverse and pavement drainage from 2980 to 4250. Due to the location of the road crest SKM have prepared the design beyond 4250, even though it is in the Brown’s road design section. The pavement drainage catchment will therefore flow into The Northern Road upgrade pavement drainage design.

Survey

RMS provided the following survey data which has been reviewed by SKM:

Ground survey within the proposed main alignment corridor.

Ground survey within in the proposed local road corridor.

0.5m contours derived from Airborne Laser Survey (ALS) over a width of approximately 600m on either side of the road.

Regional 2m contours beyond the extent of the ALS data detailed above.



4. Transverse drainage design 4.1. Estimation of design flows

Estimation of design flows for the existing and design scenarios have been determined using the Probabilistic Rational Method (PRM) for Eastern NSW as described in Section 1.4.1 of Australian Rainfall and Runoff (ARR) Volume 1 Book 5 (IEAust, 2001). Description of inputs and design flows are provided in the following sections.

4.1.1. Definition of catchments

Catchment boundaries for existing conditions and the proposed road upgrade were defined based on: detailed ground survey within the road boundary, ALS data and 2m contours beyond the boundary. Catchment areas for the existing cross drainage elements and for the proposed design crossings are provided in Appendix C. Catchment areas for the proposed transverse drainage structures are also displayed in Figure 4.1.

4.1.2. Design rainfall intensities

Design rainfall depths were estimated using the procedures set out in ARR (IEAust, 2001) and are provided in Table 4-1. One set of rainfall intensities were found to be representative of the catchments along the length of the road.

Table 4-1 – Parameters used for estimating design rainfall depths

The design criteria requires the design of cross drainage to include consideration of climate change. As noted in Section 2.1, a 10% increase to design rainfall intensities was therefore applied when deriving all cross drainage design flows.

Input Value

2 year, 1 hour intensity 30 mm/hr 2 year, 12 hour intensity 6.1 mm/hr 2 year, 72 hour intensity 1.85 mm/hr 50 year, 1 hour intensity 59.8 mm/hr 50 year, 12 hour intensity 12.1 mm/hr 50 year, 72 hour intensity 3.8 mm/hr Skewness 0.01 Geographical factor for 6 minute, 2 year storm 4.29 Geographical factor for 6 minute, 50 year storm 15.79

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Figure 4.1a Transverse drainage catchments

I:\NBIF\Projects\NB11363\Technical\GIS\Spatial_Directory\ArcGIS\NR_GIS_Dr_F001_Catchments_REVB2.mxd

Proposal boundary

LGA boundary

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Design road chainage

Transverse catchments

LOCALITY

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DRC 9870

DRC 9720

DRC 8900

DRC 11370

DRC 13900

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DRC 10970

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Kilometres

Figure 4.1b Transverse drainage catchments

I:\NBIF\Projects\NB11363\Technical\GIS\Spatial_Directory\ArcGIS\NR_GIS_Dr_F001_Catchments_REVB2.mxd

Proposal boundary

LGA boundary

! ! South West Growth Centre boundary

Design road chainage

Transverse catchments

LOCALITY

Sydney

Parramatta

Penrith

Liverpool

Sutherland

DRC



4.1.3. Design flows

The runoff coefficient (C10) used in the PRM was estimated with reference to Section 1.4.1(a) iii of ARR Vol 1 Book 5 (IEAust, 2001). Over the length of the road the C10 value varies between 0.4 and 0.53. During the development of the concept design a conservative C10 value of 0.53, applicable to the southern catchment boundary, has been applied. The PRM does not allow for reduction in flows that may occur due to farm dams located in the upstream catchments. Therefore, for the purpose of the estimation of design flows it has been assumed that any such dams are full during a design event. Details of design flows at each culvert crossing are presented in Appendix C.

4.1.4. Validation of flows

The PRM is one method for estimating design flows and is generally considered appropriate when undertaking infrastructure concept design. Another method for estimating flows is by applying a rainfall runoff model to a catchment. Models can be configured to consider variation of rainfall over large catchments, varying rainfall loss rates, catchment storage, sub-catchments, land use and channel routing. For The Northern Road a XP-RAFTS model was setup for the Lowes Creek catchment (area 1060 hectares) as a validation of the PRM. As no data was available to calibrate the model parameters used in similar projects were adopted.

The modelled XP-RAFTS peak flow was 81m3/s for the 100 year ARI event, with the 6 hour event producing the largest flow. The PRM estimate at this location is 113.5m3/s; both figures are without climate change applied to rainfall. These results show the PRM estimate is around 40% larger than XP-RAFTS generated flow for the 100 year ARI event. From this assessment it is considered reasonable to adopt the PRM which provides a conservative estimate of flow.

4.1.5. Consideration of development in small catchments

In undertaking the concept design it has been assumed that existing and future development includes/will include on-site detention facilities for all catchments greater than 10 hectares. Therefore peak flows would be at least maintained at pre-developed levels for events up to the 100 year ARI. As noted previously it has been assumed that catchments less than 10 hectares to be fully developed into residential/commercial/industrial land use will not incorporate effective detention controls. A degree of imperviousness of 75% for residential areas as nominated by Camden Council’s Engineering Design Specification has been adopted during the development of the concept design. Estimating design flows for these catchments uses the urbanisation method from ARR (IEAust, 2001) for this impervious fraction.

4.1.6. Estimation of extreme flood events

The estimation of the Probable Maximum Precipitation (PMP) was carried out in accordance with The Commonwealth Bureau of Meteorology’s publication “The Estimation of Probable Maximum



Precipitation in Australia: Generalised Short-Duration Method” (BOM, 2003). The PMP was applied to the rational method to determine the Probable Maximum Flood (PMF). The PMF was assigned an Annual Exceedance Probability (AEP) of 10-7 as applicable to catchments less than 100 square kilometres (Figure 6, ARR, Volume 1, Book 6).

Estimation of the 2000 year ARI event for the design of bridges was carried out in accordance to the procedure specified in section 3.6.2 of ARR Vol 1 Book 6 (IEAust, 2001). This uses the ratio of flows for the 50 year ARI, 100 year ARI and PMF events.

4.2. Hydraulic analysis and design

Hydraulic assessment and design of transverse drainage was done using SKM's in-house culvert design program CDMD (Cross Drainage Management Database) that uses the methodology and formula used in HEC-RAS as explained in the following sections. The key functional requirement of the transverse drainage is to provide 100 year ARI flood immunity for The Northern Road and to limit afflux to adjacent properties.

4.2.1. Calculation method

Water profiles through the pipeline are computed considering several conditions within the pipe and downstream. The Full Flow Equations are used when the water level at the downstream end of the pipe is above the pipe obvert. The friction loss in the pipe is computed using Manning’s formula:

2

32

486.1 ⎟⎟⎟

⎠

⎞

⎜⎜⎜

⎝

⎛=

AR

QnLhf

Where: hf = friction loss (m) L = culvert length (m) Q = flowrate in the culvert (m3/s) n = Manning’s roughness coefficient A = area of flow (m) R = hydraulic radius (m) = A/P P = wetted perimeter (m)

If the calculated upstream water level is above the pipe obvert, the result is accepted. If not, the water level is re-calculated using the Direct Step Method. The Direct Step Method is used for determining the surface water profile within a pipe flowing partially full. The Direct Step Method uses Bernoulli’s equation for determining the change in energy for a given change in water depth.



Inlet Control water levels are determined using the equations developed by the US National Bureau of Standards, the US Bureau of Public Roads and other entities. The experiments from which these formulas were derived formed the basis of the US Federal Highways Administration Inlet Control Nomographs which are widely adopted in Australia and are replicated in the Austroads - Waterways Design Manual (1994).

CDMD uses the following formula, outlined in the HEC-RAS reference manual, in the calculation of inlet control.

Un-submerged Inlet:

. 0.5

Submerged Inlet:

. 0.5

All units are English Units. Input and results to CDMD are converted by the program.

D = Interior barrel height, (ft) Hc = Specific Head at critical depth Q = discharge (cfs) A = Full Cross Sectional Area (ft2) S = Barrel Slope K,M,c,Y = equation constants that vary depending on culvert shape and entrance conditions.

Between . = 3.5 and 4.0 for circular culverts and 2.0 and 4.0 for box culverts, the inlet control

transitions between un-submerged and submerged states. If . falls between these two values,

CDMD will interpolate between the un-submerged HWi when . = 3.5 (2 for box culverts) and

the submerged HWi when . = 4.0, to find the headwater level. This approach has been shown

to produce a smooth transition between the un-submerged and submerged values.

Efforts to adopt the formula and coefficients given in the publications Hydraulic Computer Program (HY) 1, FHWA, 1969, (Circular Culverts) and Hydraulic Computer Program (HY) 3, FHWA, 1969 (Box Culverts) have lead to erroneous results when the ratio of flow to area is very small or conversely very large. In the range of 2.0 to 4.0, the linear interpolation approach differed only marginally from the HY1 and HY3 formula results.



4.2.2. Existing conditions

Hydraulic assessment of the existing culverts capacity was undertaken. Consideration was given to inter-catchment flow when ponded water surcharges behind the culverts. The resultant flows at each cross drainage location are provided in Appendix D. This shows that many crossings have a capacity less than the 100 year ARI design standard. Therefore upgrade of the road requires increased culvert sizes to provide 100 year ARI flood immunity.

4.2.3. Concept design

The transverse drainage design has been sized to address the objectives and criteria as noted in Section 2. Additionally the concept design has adopted an odd number of cells where multiple box culverts are proposed to allow for the use of link slabs. The cost effectiveness of providing link slabs should be considered at detailed design.

At some low points the proposed road is close to/lower than the natural surface level. At these locations inlet pits have been incorporated into the concept design to provide the required cover. The sizing of culverts has been based on the adoption of a conservative assumption of a 50% blockage at headwall inlets. The adoption of this approach allows for either pits or headwalls to be specified in the detailed design without resulting in a notable increase in required culvert sizes.

The following information is provided in Appendix D of this report:

Sizes of transverse drainage provided in the concept design.

The level that controls the design (either the level prior to inter-catchment flow or minimum level of the road).

Upstream water levels for both the existing and design case with no blockage and the design case with 50% blockage.

A perched low point (sag) occurs in the cut between chainage 1700 and chainage 1800 on the northbound carriageway. A number of design options were considered including piping the flow under the upgraded alignment or diverting the flow south using a fill embankment. The localised filling of the low point was considered the best design outcome (refer drawing NB11363-ECC-DG-2104 for fill extents), diverting the flow south towards the lower berm drain and discharging towards the culvert under Hillside Drive. The flow regime in this area will change as there will be a reduction in flow that traverses to the eastern side of the carriageway, parallel to Crain Circuit, and an increase in flow under the new Hillside Drive. The increase in flow will be managed by an open channel discharging to Narellan Creek on the downstream side of The Northern Road bridge.



4.2.4. Environmental considerations

Receiving waterways along the upgrade were assessed by SKM’s aquatic ecologist to determine those that would require the incorporation of fish friendly crossings in the design. The assessment concluded that all named crossings should be designed to consider fish passage, which includes:

Narellan Creek

Cobbity Creek

Lowes Creek

Thompsons Creek

The crossings of Narellan and Thompsons Creeks are facilitated through the provision of bridges which provide a suitable passage for fish.

The crossings of Cobbity and Lowes Creeks are facilitated through the provision of box culverts. Fish passage will need to be designed at these locations and these have not been developed as part of the concept design (it is assumed that this task will be undertaken during detailed design).

4.3. Culvert outlet protection measures

Where exit velocities from drainage culverts are sufficiently high and the receiving channel is assumed to be erodible, an elongated scour hole could form unless protective measures are provided. Selection of the most appropriate scour protection measure depends on the velocity and Froude Number at the culvert outlet and the natural velocities and flow regime in the receiving watercourse.

The Froude number is a dimensionless value commonly used to define flow regimes. A value less than 1.0 is sub-critical flow which is typified by low energy flow state. A value above 1.0 indicates super-critical flow which is typified by fast flowing water of high energy.

The culvert outlet protection measures have been conservatively designed for the 100 year ARI event for the purpose of the REF. The design standard of the culvert outlet protection measures should be reviewed at detailed design. Generally a 20 year ARI event would be adopted with occasional repair expenditure accepted rather than the increased cost of larger outlet structures.

4.3.1. Energy dissipators

The following approach has been adopted when identifying locations that require energy dissipators:

If the Froude number for flow discharging from a culvert is 1.3 or less, then no energy dissipator is required.



If the Froude number in the receiving channel is greater than 1.0 (super-critical flow) then no energy dissipator is required.

If the Froude number in the receiving channel is less than 1.0 (sub-critical flow) and the Froude number for flow discharging from a culvert is greater than 1.3, then an energy dissipator is required.

Where it has been identified that energy dissipaters are required, the RMS Type A basin has been adopted as a suitable solution. This type of dissipator is comprised of a rock lined pool and a rip rap apron and is suitable when Froude numbers are less than 3.0. The pool depth and length is designed to induce and fully contain a hydraulic jump so that the jump occurs at a location treated to prevent scour. The design procedure is outlined in the RMS’s Road Design Guide Section 8 (RTA 1993). The requirement for Type A energy dissipaters should be reviewed at detailed design according to the specific site conditions at each location.

4.3.2. Rock lined transition apron

It is assumed that detailed design will use concrete wingwalls/headwalls with concrete or rock aprons upstream and downstream of all drainage culverts. When the outlet velocities are low, this apron alone would be sufficient to protect against scour.

Where the outlet velocity is sufficient to cause scour in the receiving watercourse but there is little chance of a hydraulic jump occurring, stream bed protection is proposed. The length of the transition apron was determined using the methodology outlined in US Department of Transportation publication HEC-14 – Hydraulic design of Energy Dissipators for Culvert and Channels, Section 10.2 (FHWA, 2006).

If there is an elevated tailwater level, Figure 8.2.8 of the RMS’s Road Design Guide (RTA 1993) has been used to identify the minimum required channel length. The required minimum width at the end of the transition apron has been calculated by applying the following formula:

aDxVQWa =

Where Wa = Minimum width of transition apron at end - m Q = Flow through Culverts – m3/s D = Depth in receiving channel - m Va = Acceptable velocity at end of apron - m/s (generally 1.5m/s) The location and type of erosion protection at each transverse drainage location is given in Table 4-2. Details of outlet velocities and sizes of works are provided in Appendix E.



Table 4-2 – Culvert outlet protection measures

New Culvert ID Outlet Treatment New Culvert ID Outlet Treatment

C1.17 Rock Apron C9.30 Rock Apron C1.39 Type A Energy Dissipater C9.75 Type A Energy Dissipater C2.16 Type A Energy Dissipater C9.87 Type A Energy Dissipater C2.45 Type A Energy Dissipater C10.38 Type A Energy Dissipater C2.65 Rock Apron C10.39 Type A Energy Dissipater C2.95 Rock Apron C10.61 Rock Apron C3.10 Type A Energy Dissipater C10.80 Rock Apron C3.24 Design by others C10.97 Type A Energy Dissipater C3.65 Design by others C11.37 Type A Energy Dissipater C4.52 Rock Apron C12.05 Rock Apron C4.65 Rock Apron C12.35 Rock Apron C4.90 Type A Energy Dissipater C12.61 Type A Energy Dissipater C4.95 Type A Energy Dissipater C12.68 Rock Apron C5.20 Type A Energy Dissipater C12.95 Rock Apron C5.35A Type A Energy Dissipater C13.25 Type A Energy Dissipater C5.35B Type A Energy Dissipater C13.76 Type A Energy Dissipater C6.07 Rock Apron C13.88 Rock Apron C6.10 Type A Energy Dissipater C13.90 Type A Energy Dissipater C6.40 Rock Apron C13.92 Rock Apron C6.65 Type A Energy Dissipater C14.20 Rock Apron C7.25 Rock Apron C14.34 Rock Apron C7.75 Type A Energy Dissipater C14.52 Type A Energy Dissipater C8.95 Rock Apron C14.60 Type A Energy Dissipater C9.00 Rock Apron

4.4. Open channels

Open channels are provided to discharge concentrated flow into a defined watercourse or locally divert a low point to a culvert, these do not include swales used for water treatment which are addressed in Section 5. The design criteria requires a 5 year ARI design for open channels however where open channels are used to convey transverse drainage catchments or drain through existing properties a 100 year ARI design standard has been applied to avoid potential flooding impacts to properties.

All open channels were modelled in 12D to define the required boundaries for all works. Drainage easements have been proposed for areas where channels are required to continue beyond the project boundary prior to joining existing water courses.



In this concept design, open channels such as: catch drains, table drains, depressed median, culvert tail in and tail out channels and diversion drains have been designed by providing a standard base width and nominal depth based on experience drawn from similar projects. In addition, the following assumptions have been made when designing open channels:

Catch drains at the top of cut batters are designed with a 0.5m base width and 0.225m depth with a nominal 3m offset to the top of the cut batter. All catch drains are taken to be concrete lined.

Toe-of-batter drains and diversion drains are provided at the toe of fill embankments where the existing ground slopes towards the embankment. These drains are provided with trapezoidal shape having 1m base width and 0.5 m depth and are jute mesh lined.

For the culvert tail-in and tail-out channels that run through private property, the following works have been carried out:

- Where the 'Hydroline' layer in NSW Department of Land GIS map shows an existing water course and the available survey information also indicates natural depression/water course, then no drainage easements have been proposed. In such situations, tail-in/tail-out channels have been extended with minimum 0.5% longitudinal grade into the private property to match with the existing ground. The channels have been sized for 100 year ARI where there are existing houses next to the tail-in/tailout channels. Where there are no existing houses in close vicinity of the channels, the channels have been sized for 5 year ARI bank-full capacity

- Where there is no existing water course through the private property, an easement has been proposed to the extent of the channel works and channels have been extended to nearest water course/dam with a minimum 0.5% longitudinal grade

- Where the culvert tail-in channel does not form part of a natural depression/water course and is merely an overland flow path discharging into a culvert, then the tail-in channel work has been designed with maximum 1 in 4 grade. The tail-in channel in such situation needs to be lined with rocks.

- All other tail-in and tail-out channels are assumed to be lined with vegetation.

Earth bunds have been provided to direct flows to culvert headwalls where excavated channels would be unfeasible due the required channel design levels.

Level spreaders and earth bunds have also been used to provide a measure of water quality treatment and to reduce discharge velocity.

Minimum grade of any open channel is assumed to be 0.5%.



All open channels will need to be hydraulically designed to confirm size and lining requirements during the development of the detailed design for the proposed works.

4.5. Major creek crossings

The proposed duplication of the existing bridge crossings of Narellan Creek at chainage 1,080 and Thompson Creek at chainage 12,280, as well as the Lowes Creek crossing at chainage 8,900 were hydraulically assessed using the modelling software HEC-RAS (Version 4.1.0). Steady-state models were developed to represent the existing case and proposed design case in order to:

Determine design flood levels and velocities for the design of the bridge structures and the road upgrade to ensure the required flood immunity is met. Events up to a 2000 year ARI event were assessed.

Assess potential impacts due to flooding on adjacent land upstream and downstream of the bridges.

Assess the effects of the road on regional flooding for the PMF or extreme flood event.

Estimate 2000 year ARI scour depths at the bridge abutments and piers.

Details of the modelling and outcomes for the design of bridges and major structures are provided in NB11363-ECT-RP-0051 - Bridge Concept Options Report. A brief description at each site is given below.

Narellan Creek

The cross drainage culvert immediately north of the Narellan Creek bridge was included in the Narellan Creek bridge HEC-RAS model as it assists in conveying large floods across the floodplain. The existing bridge deck level at the road crest is approximately 73.7m AHD, the deck thickness is approximately 500mm, and the minimum bridge soffit level (allowing for the road crossfall) is approximately 73.0m AHD.

The proposed new bridge is located on the downstream side of the existing bridge. It is a three span bridge with the two piers aligned with the outer piers of the existing bridge. It will have a higher deck level than the existing bridge, and the minimum soffit level will be approximately 500mm lower at RL 72.5m due to an increased deck thickness. The addition of the new northbound carriageway will alter the profile of the road embankment weir, resulting in the new duplicated road overflow level increasing by approximately 200mm compared to the existing road overflow level.

Survey was obtained from RMS for this project to develop a HEC-RAS model at this location. Observed flow and water level data was not available to calibrate the model. Selected hydraulic



model parameters were based on observations from site. HEC-RAS modelling indicates that duplicating the existing bridge will satisfy the flood immunity requirements.

Lowes Creek

The existing culvert crossing at Lowes Creek comprises 3 x 3000mm x 3000mm Reinforced Concrete Box Culverts (RCBC) in the main channel and 4 x 600mm diameter Reinforced Concrete Pipe (RCP) culverts across the floodplain north of the main channel culverts. The existing road minimum overflow level is RL 68.3m.

The proposed concept design provides 8 x 2400mm x 2100mm RCBCs for the main channel and 25 x 1800mm x 900mm RCBCs across the floodplain. The minimum road overflow level of the upgrade will be raised 1.2m to RL 69.5m.

HEC-RAS modelling indicates the existing road would be overtopped in the 100 year ARI climate change event. The size of cross drainage was substantially increased such that the raised road is not overtopped for the design event. Box culverts are proposed on the main Lowes Creek channel as this water course is nominated for fish passage.

Thompsons Creek

Thompsons Creek crosses The Northern Road at approximate chainage 12,280. There is a twin 10m span bridge currently over Thompsons Creek. The existing bridge deck level at the road crest is approximately 73.1m AHD, the deck thickness is approximately 500mm, and the minimum bridge soffit level (allowing for the road crossfall) is approximately 72.5m AHD.

The proposed new bridge is located on the upstream side of the existing bridge. It is a single span bridge with abutments aligned with the existing bridge. It will have a higher deck level than the existing bridge and a minimum soffit level approximately 500mm lower at RL 72.0m due to an increased deck thickness. The minimum road overflow level of the upgrade will be approximately 100mm lower than the existing road overflow level due to a change in the vertical road alignment south of the bridge. The lowest point in the new road profile will be approximately 120m south of the bridge.

Results from HEC-RAS modelling shows that duplicating the existing bridge crossing over the main channel of Thompsons Creek provides the required flood immunity.



5. Pavement drainage design 5.1. Design overview

The pavement drainage system consists of gutters, pits, channels and pipes which collect and convey stormwater safely from the road pavement prior to discharging into receiving waterways. Where possible, stormwater will be conveyed through a water quality treatment device before being discharged into waterways. The pavement runoff from the proposed works is collected via SA type kerb and gutter, median drains or catch drains at the toe of the road embankments. Water quality treatment along the upgrade consists of vegetated swales and spill basins at critical locations (refer to Section 7).

The pavement drainage has been designed to minimise the number of pipes crossing under the pavement and also to minimise the total length of pipes and number of pits required for the upgrade, whilst meeting the design standards. In areas where the pavement has a standard 3% crossfall, pavement drainage lines have been placed under the SA gutter on both carriageways. However, in the areas where the road is in cut, the main drainage lines are along the central median to avoid deep trenches along the toe of the road cut batter. Where the road is in super elevation, drainage lines have been placed under the median and under SA kerbs on the low side of superelevation to reduce the amount of pipes crossing under the pavement.

When the road has a fill embankment height greater than 3m, the pipe drainage network has been designed to discharge via batter chutes leading to an open channel before entering existing watercourses. Where the fill height is less than 3m pavement drainage has been designed to discharge to drainage swales before entering the existing watercourse. Additionally, where pavement drainage discharges to a sensitive watercourse, stormwater is passed through a water quality basin prior to entering the watercourse.

The pavement drainage design criteria adopted in the development of the concept design is detailed in Section 2 of this report.

5.2. Pavement drainage hydrology

Catchment areas for hydrological calculations were determined using the design surface modelled in 12d. Hydrological calculations were carried out using the storm analysis module in 12d. The hydrology method used was based on the Rational Method.

The pavement drainage was designed for the 20 year ARI design storm, which is higher than typically provided, therefore the climate change impact to rainfall intensity was not considered in designing the pavement drainage system.



5.3. Pavement drainage Concept Design

5.3.1. Pit locations

Pit spacing is a function of gutter capacity, contributing catchment area, longitudinal grade of the road alignment, pit capture capacity and design performance requirements.

Where runoff is collected in a gutter or median drain, the flow depths along the kerb or drain were checked at one metre intervals to ensure water depth and width remained within design limits. These checks were used to inform pit placement.

5.3.2. Pipe sizing

A hydraulic grade line analysis for proposed pits and pipes was undertaken using the storm analysis module within 12d. The module uses a Direct Step Method to assess partial pipe flow water surface level and Manning’s equation for full pipe flows.

A pit freeboard of 150mm has been adopted during the hydraulic analysis of the piped systems. While sizing the pipes, no blockages at pits have been considered.

The pipe system has been designed to have an absolute minimum pipe grade of 0.5%. The adopted maximum water velocity in pipes is 8m/s while the adopted minimum water velocity is 0.6m/s for a 6 month ARI storm event.

5.4. Pavement drainage at road tie-ins

At the southern road tie-in, The Northern Road is falling from a high point approximately 45m south of the tie-in. This section of the road has an existing piped drainage system that discharges into Harrington Park Lake. Existing pits and pipes in the vicinity of the tie-in will need to be removed to enable the design works to be constructed. The proposed concept drainage design for the drainage network in the vicinity of the tie-in has been designed to accommodate catchment areas from the existing road.

At the northern tie-in there are no existing drainage pits or pipes. Pavement runoff discharges as sheet flow into existing vegetated table drains that eventually flow into Badgery’s Creek. Road runoff from the upgrade will be captured and discharged to a new open channel on the eastern side of the road and taken approximately 130m beyond the end of work to Badgery’s Creek.

The proposed road upgrade work also involves intersection and associated tie-in works to the existing and new local roads at 21 locations. The design objective at local road tie-ins is not to exacerbate existing drainage issues on local roads or impact on the drainage design for The Northern Road upgrade. Where a local road drains towards The Northern Road, drainage pits have



been provided along the local road to limit the width of flow at the intersection. These pits connect to the main alignment drainage system. Where the local roads grade away from The Northern Road, pipes have been graded as per the local road profile and discharged to the existing ground or natural watercourse via headwalls/surcharge pits (whichever is suitable). Where feasible, existing drainage in local roads is to be retained and suitable connections to the proposed drainage network are to be provided.

5.4.1. Existing pipe drainage

The existing stormwater pipes and pits in The Northern Road and local roads have been considered as part of pavement drainage design and assessment for the upgrade.

At Fairwater Drive, there are existing pits and pipes in the road that convey runoff into the existing lake. However, the horizontal and vertical designs of the Fairwater Drive have changed significantly to suit The Northern Road upgrade. Due to these changes, the existing drainage network (pits and pipes) will have to be removed and replaced with a new drainage network to replicate the existing system (i.e. same discharge conditions).

Similarly, the existing pits and pipes in Hillside Drive are to be removed and new drainage pits and pipes are to be provided to allow for changes in the road horizontal and vertical geometry.

All other existing pavement drainage pits and pipes will be removed unless noted otherwise on the drainage plans.

5.5. Pavement surface flow

Depth of flow calculations for the assessment of aquaplaning effects has been carried out for the proposed road surfaces using the method developed by Gallaway et al (1970) as described in the 1986 NAASRA publication ‘Guide to the Design of Road Surface Drainage’. For The Northern Road it is assumed that the new pavement will be dense graded asphalt for which the texture depth is approximately 0.9mm. To provide a conservative assessment depth of flow calculations have considered depths between 0.3mm and 1.2mm.

The most critical areas to be checked for pavement surface flow depth are generally: along super elevation transitions, at intersections, in auxiliary lanes at approaches to intersections and at ramps. The length of the flow paths in these areas has been determined using the Rain Drop tool in 12D software program. Flow depth calculations were undertaken for both the four and six lane upgrade options.

The calculation results showed that the flow depths are generally not greater than 4.0mm during a 50 mm/hr rainfall event. However, there are a few locations where flow depths are slightly greater



than 4.0mm (up to 4.18mm). These exceedances in depths are minor and further investigations to limit the flow depths to a maximum of 4.0mm would need to be undertaken at detailed design.

The results of aquaplaning checks for the four and six lane carriageway options are provided in Appendix G of this report.

5.6. Subsurface drainage

Typical details for subsurface drainage are provided with the pavement drawings. The location of subsurface drainage lines are not included on the drainage drawings.

5.7. Consideration for temporary works

Temporary drainage requirements based on the construction staging plans have been assessed and drainage has been provided to ensure that discharge of stormwater runoff is maintained at all times during the construction of the works. An overview of the construction staging is described below:

Stage 1

Stage 1 of the road construction involves the construction of earthworks, drainage and pavement for the two additional lanes adjacent to the existing carriageway. The existing carriageways will remain open to traffic to accommodate traffic movements until construction of the additional lanes is complete.

To facilitate the flow of runoff from upstream external catchments to the downstream watercourses, existing culverts will be retained during the course of Stage 1. Proposed culverts will be constructed under the new pavement. Runoff from the existing culverts to the proposed culverts will run through the proposed median. Where it is not possible to provide a suitable flow path through the median, the existing culverts will be extended under the new pavement as a temporary measure to discharge runoff to the drainage outlet. All open channels will be constructed to divert runoff to the culvert inlet areas.

Pavement drainage will be installed beneath the new pavement being constructed during this stage. This will involve construction of pits and pipes on the low kerb side and pits and pipes in the median. Drainage will be discharged to the outlet proposed in the drainage design drawings. Where it is not possible to discharge the drainage to the outlet shown in the drawings, then temporary pipes will be constructed along the proposed median and drainage will be discharged to the nearest cross drainage. Alternatively, temporary cross drainage will be constructed under the new pavement to facilitate discharge to an open drain.



Stage 2

Stage 2 of the proposed road work involves the construction of road pavement, drainage and the earthworks of the remaining two lanes. Traffic will be diverted onto the two newly constructed lanes constructed in Stage 1. The culverts constructed in Stage 1 will be extended to their full lengths as per the ultimate design. The remainder of the pavement drainage will be constructed in this stage and connected to the drainage network constructed in Stage 1.

The above design, however, is subject to construction work methods adopted at the detailed design stage when construction sequence and methodology will be better understood. Potential contractors may identify other staging options suitable for the road upgrade. Accordingly, a further review of the temporary drainage works needs to be undertaken at detailed design stage.



6. Impact assessment Upgrade of The Northern Road and associated drainage has the potential to adversely impact on private property both upstream and downstream of the road corridor. However it should also be noted that the upgrade of the drainage network can potentially also improve flow or inundation conditions at properties. For the purpose of the development of this concept design only adverse impacts have been considered.

6.1. Upstream properties

Upstream properties may be subject to increased water levels if the existing road level is raised or the formation is extended upstream. Hydraulic modelling results (refer to Appendix D) show that in all cases the proposed culverts will result in lower 100 year ARI upstream water levels compared to the existing conditions (when blockage is not considered). The upgrade would therefore not result in any adverse flooding impacts to adjacent upstream properties for the 100 year ARI event.

As the new road will be raised in some locations to provide the required 100 year ARI flood immunity, adverse impacts to upstream properties may occur for extreme storm events (e.g. the PMF) where the capacity of the upgraded culverts is exceeded. Upstream flood levels for an extreme event would be controlled by the road minimum overflow level or overflow levels to adjacent sub-catchments. Locations along the upgrade where adverse PMF impacts to upstream properties are expected are identified and further described in Section 6.4.

6.2. Downstream properties

Some properties downstream of the road will be subject to increased peak flows and velocities as a result of the upgrade. The enlargement of existing undersized culvert structures to provide the new road with 100 year ARI flood immunity will cause a redistribution of flows at some locations. Additionally, the increased paved road area will also contribute to increased peak flow rates in downstream receiving channels.

An assessment of the change in flows at the downstream property boundary has been undertaken using CDMD. Pre and post development peak flow rate calculations at each discharge point have been undertaken for the 10, 20 and 100 year ARI storms and assessed for any adverse impacts (refer to Appendix F for results).

Peak flow rates at the downstream boundary are in most cases the combination of flow through transverse culverts and flow from the road pavement catchments. Flows through the transverse culverts for pre and post developed conditions were estimated using the PRM assuming existing levels of development in the catchments. Any overflows to adjacent culverts as a result of hydraulic capacity were taken into account for the pre-developed case. Flows from the road pavement



catchments were estimated using the Rational Method and take into account the percentage imperviousness of the pre and post developed conditions. All flow rates were estimated using design rainfall intensities factored for the impact of climate change.

Peak flows from two or more catchments were combined using partial area adjustments. If the nominated rational method storm duration is shorter than the catchment travel time, the program will adjust the contributing catchment area before calculating peak runoff. The following formula is used for partial area adjustment Tc = 0.76 A0.38. Peak flow rates from the adjusted individual catchments are then added together to calculate the combined peak flow rate.

Locations were identified where there is an increase in downstream flows and there are existing properties susceptible to increased flood levels. The increase in peak flow rate at drainage outlets adjacent to property boundaries has been managed by providing a suitably sized channel to cater for the 100 year ARI event (with climate change). Works have been sized such that afflux in the water courses upstream and downstream of the culverts would not result in adverse impacts to adjacent properties.

A summary of the locations where the upgrade will cause an increase in downstream flows and a description of the impact to existing properties is provided in Table 6-1.



Table 6-1 – Summary of increased downstream flows and impacts

Chainage Culvert

ID

Existing 100yr peak flow (m³/s)

Proposed 100yr peak flow (m³/s)

Downstream impact

1390 C1.39 0.994 1.898 Increase in peak flow and velocity has been mitigated by designing downstream channel to the 100 yr peak flow and velocity. 2160 C2.16 1.439 3.413 Increase in peak flow and velocity as a result of the upgraded road and culvert, however no existing dwellings at risk. 2650 C2.65 2.518 9.963 Significant Increase in peak flow and velocity at the outlet of this culvert as a result of the upgraded road and culvert, however the peak

flow in the water course within the private property will be the combined effect of runoff from C2.65 and C2.45 and will not be signficant. There are no exisitng dwelling adjacent to the water course, therefore, not impacted by the upgrade.

2950 C2.95 0.607 0.69 Small increase in peak flow and velocity in the downstream channel. Channel has been located within the road corridor and sized for the 100 yr peak flow, thereby mitigating any potential flood impact to adjacent property.

3100 C3.10 0.758 3.333 Increase in peak flow and velocity as a result of the upgraded road and culvert, however no existing dwellings at risk. Also, It should be noted that there will be no impact on down stream flows as the flows from culverts C3.24 and C3.10 combine 160m downstream as in the existing situation with C3.24 having reduction in peak flows.

4520 C4.52 2.889 5.178 Increase in peak flow and velocity as a result of the upgraded road and culvert, however no existing dwellings at risk. Also, It should be noted that there will be no significant impact on down stream flows as the flows from culverts C4.52 and C4.65 combine at the dam within the private property with C4.65 having reduction in peak flows.

4900 C4.90 3.8 6.523 Increase in peak flow and velocity due to upstream catchment diversion and increased pavement drainage catchment. The 100r ARI peak flood level in the downstream channel is estimated to increase about 80mm. The increased flood level would remain below the ground level at the existing structure by about 100mm so would not cause inundation of the structure.

4950 C4.95 3.12 4.769 Increase in peak flow and velocity due to diversion of upstream catchment and increased capacity of downstream culvert. Downstream channel has been designed for the 100yr peak flow and velocity.

6070 C6.07 0.027 0.431 Increase in peak flow and velocity due to diversion of catchment. Downstream channel proposed within the road boundary and has been designed for the 100yr peak flow and velocity to discharge to outlet of culvert C6.40.

6400 C6.40 4.702 8.267 Increase in peak flow and velocity due to increased capacity of the culvert. No existing dwellings at risk, therefore, no downstream channel works to contain the increased peak flow in 100 year ARI has been considered. The increase in the 100yr flow downstream will cause a 50mm increase in the 100yr flow depth over the existing dam wall (increasing from 0.11m to 0.16m). This is considered acceptable and no works to the existing dam wall are proposed.Downstream of the existing dam, the peak flow rate will not increase signficantly due to runoff from C6.65 arriving downstream of the dam with reduced peak flow rate.

7750 C7.75 0.892 1.549 Increase in peak flow and velocity due to increased pavement drainage catchment. No existing dwellings at risk. Downstream water course is a wide natural depression currently caters for the existing culvert runoff. Channel work to cater for increase in peak flow is not required.

9300 C9.30 N/A 0.31 Culvert down stream channel has been design for 100 year ARI to avoid adverse impact to adjoining property and discharges to inlet of culvert C9.05.



Chainage Culvert

ID

Existing 100yr peak flow (m³/s)

Proposed 100yr peak flow (m³/s)

Downstream impact

9870 C9.87 1.695 3.287 Flows downstream will approximately double mainly due to the new culverts increased capacity. The proposed downstream channel through the property has been designed for 100 year ARI ensuring that flow is contained within the channel and therefore will have no flooding impacts to the property. The design velocity is less than the existing and as such will not have any scour issues. The upgrade will cause a small 3% increase in the combined peak 100yr flow from culverts C9.75 and C9.87. This impact will diminish downstream of TNR as additional catchment areas enter the watercourse.

10390 C10.39 N/A 1.155 The channel downstream of the culvert has been designed for 100 year ARI and does not impact adversly on the adjoining property. 10380 C10.38 N/A 1.31 The culvert discharges to the existing natural water course which is of sufficent capacity to cater for the flows. 10800 C10.80 2.242 2.734 The culvert downstream channel has been sized for 100 year ARI to ensure that there will be no adverse impact on the adjoining

property. 11370 C11.37 0.678 1.003 There wil be an increase in peak flow rates and flood level which will be accomodated in the existing channel and will not impact on the

existing property. 12610 C12.61 1.723 2.572 Significant increase in peak flow rates has occured due to additinal pavement drainage catchments . Downstream channel throgh the

private property has been designed to ensure that the flow is contained within the channel and therefore will have no flooding impacts to the property.

12680 C12.68 N/A 2.333 The propopsed down stream channel has been designed such that the flow is contained within the channel and therefore will have no flooding impacts to the property.

13250 C13.25 1.855 2.597 Significant increase in peak flow rate has occurred. However, an assessment of the propopsed down stream channel and water course shows that the flow is contained within the channel/water course and there will be no flooding impacts to the property. The 100yr flood level over the downstream dam spillway will increase about 40mm due to the increased flows (from RL 85.7 to RL 85.74). The existing dwelling 30m south of the dam is at a RL of 88.0m and will therfore not be affected.

13760 C13.76 N/A 1.41 The proposed downstream channel is within the road boundary and sized such that the flow does not impact adversly on the adjoining property.

13880 C13.88 N/A 2.346 There will be increase in peak flow rate, however, the down stream channel and water course are of sufficient capacity and that there will be no adverse flooding impacts to the property.

13920 C13.92 0.219 0.29 Significant increase in peak flow rates occur , however, no dwelling/property would be adversly impacted. 14200 C14.20 2.859 3.686 Significant increase in peak flow rates has occurred due to flow diversion from adjacent culvert C14.34. However, the downstream

channel has been designed with a capacity not to cause any adverse impact to downstream flood.. 14520 C14.52 N/A 0.267 The downstream tail out channel has been sized to ensure that therefore will be no flooding impacts to the adjoining property property. 14600 C14.60 N/A 0.881 Pre and post developed catchment seems to be similar at this location therefore it is envisaged that there will not be signficant increase

in peak flow rates. The downstream channel has been sized to ensure that there is no adverse flooding impact on the adjoining property.



6.3. Existing farm dams

There are some existing farm dams close to the proposed upgrade formation that are potentially impacted by the road works. At these locations, RMS has directed that existing dams are to be maintained where possible. Where this is not possible the following strategy has been adopted during the development of the concept design:

If the proposed road works impact on the dams marginally, dam walls and associated spillways would be reconstructed to suit.

If more than half of the dam is impacted, the dam would be filled and roadworks and associated drainage works will be constructed on top of the filled dam.

The existing farm dams impacted by the proposal are identified in Table 6-2.

Table 6-2 – Existing farm dams impacted by The Northern Road upgrade

Chainage E / W Proposed works

6000 W Reconstruct dam immediately south of Marylands Link Road 1 near the inlet to culvert C6.10

6300 W Reconstruct dam adjacent to the northbound carriageway 7200 E Reconstruct dam immediately south of Marylands Link Road 2 near the inlet to

culvert C7.25 8100 W Reconstruct dam impacted by Marylands Link Road 3 9200 W Remove dam under and adjacent to the northbound carriageway 9650 W Reconstruct dam adjacent to the northbound carriageway near the inlet to culvert

C9.75 9750 E Remove dam adjacent to the southbound carriageway at the outlet of culvert C9.75 9860 E Remove dam adjacent to the southbound carriageway at the outlet of culvert C9.87 10400 E Remove dam under the new Belmore Road 10580 W Remove dam under the northbound carriageway 10750 W Reconstruct dam adjacent to the northbound carriageway 12380 W Reconstruct dam immediately north of Lea Road near the inlet to culvert C12.35 12390 E Remove dam adjacent to Lea Road 12400 W Remove dam under the northbound carriageway near the inlet to culvert C12.35 12630 W Remove dam at the southwestern corner of Badgery’s Creek Road intersection 12860 E Reconstruct dam adjacent to the southbound carriageway 13250 E Reconstruct dam adjacent to the southbound carriageway near the inlet to culvert

C13.25 13300 E Reconstruct dam adjacent to the southbound carriageway near the inlet to culvert

C13.25 13420 E Reconstruct dam adjacent to the southbound carriageway at the existing Derwent



Works for adjustments to dams will generally require the creation of easements or the purchase of land to manage flows on private property. The concept design provides conservative easement estimations for such works, however these should be verified during the development of the detailed design through direct consultation with landholders. The concept design does not include the design of dam adjustments within private properties as this would be subject to consultation with property owners. It has been assumed that this work will also be undertaken as part of the detailed design.

The drainage design for The Northern Road upgrade does not discharge any pavement drainage direct to the existing farm dams to minimise water quality impacts. It is also noted that during the estimation of design flows it has been assumed that dams are full and would not attenuate catchment flows, therefore any reduction in storage volume would not impact design flows.

6.4. Impacts to regional flooding – Probable Maximum Flood

For extreme flood events, such as the PMF, the objective is not to exacerbate flooding of key evacuation routes or critical buildings such as: hospitals, emergency services buildings or buildings that are difficult to evacuate (e.g. nursing homes). As most catchments along The Northern Road upgrade have not been developed yet, planned evacuation routes and the locations of emergency services facilities is not known. Assuming all areas adjacent to The Northern Road would include residential development and associated emergency services any floodplain management plans developed for existing and future developments would need to consider inundation in a PMF. It is assumed that impacts in a PMF within the Oran Park and Harrington Park development areas will be addressed by the designers for these developments.

The cross drainage has been designed to convey the 100 year ARI event as specified in the RMS design criteria, however in larger events water would pond against the road formation until it is overtopped or overflow occurs into adjacent catchments. In such instances where water ponds against an embankment there is a risk of embankment failure resulting in a rapid release of water.

Road 13760 W Reconstruct dam adjacent to the northbound carriageway near the inlet of culvert

C13.76 13780 E Remove dam under the new Derwent Road at the outlet of culvert C13.88 13900 W Reconstruct dam adjacent to the northbound carriageway near the inlet to culvert

C13.90 14170 W Remove dam adjacent to the northbound carriageway 14550 W Remove dam under the new Mersey Road 14580 E Reconstruct dam north of Mersey Road near the inlet of culvert C14.60 14600 W Reconstruct dam north of Mersey Road



Locations along the upgrade where there would be an increase in the upstream PMF level were identified according to where the new embankment height would be greater than 2.0m. These locations were identified as the watercourses at culverts C6.40, C7.75, C9.75, C10.61 and C12.95. Based on the available survey at these locations, the increased maximum depth of inundation upstream of the road would not result in an increase to the number of existing houses inundated. This assumes that any existing dwelling within the floodplain is at or near natural surface levels. For example, at the Lowes Creek crossing, the new road low point would be raised 1.2m higher than the existing low point to provide the required flood immunity and cover over the new culverts. The existing floodplain upstream of the road is predominantly undeveloped, comprising large rural sized lots. Three existing lots would be inundated by the existing upstream PMF level. The proposal would cause a 0.85m increase in the upstream PMF level, however this would not increase the number of existing properties affected. These effects should be taken into consideration when considering future land use planning in any areas upstream of The Northern Road.

The flow distribution at cross drainage locations during an extreme event would not change between existing and proposed conditions, thus design would not result in adverse flooding conditions. This condition is to be reassessed during detailed design and design of future release areas where local roads or other earthworks may alter flow regimes for an extreme event.



7. Water quality 7.1. Construction phase

Techniques to reduce potential water quality impacts and prevent degradation of downstream waterways include the use of: sedimentation basins, onsite and offsite diversion drains, sediment fences and erosion controls at the source. These techniques, controls and required maintenance procedures are described in the Blue Book (Soils and Construction, Landcom 2004 and DECC 2008).

7.1.1. Sediment basin sizing

The design criteria for the temporary water quality treatment controls used during the construction phase are aimed at meeting the performance objectives and requirements of the Blue Book.

The preliminary sediment basins for The Northern Road upgrade have been designed as Type D as confirmed by the site specific soil test results (refer to Appendix H). The basins will provide sufficient volume to capture the design rainfall depth (settling zone) and an additional volume for storage of sediment (storage zone). The settling zone volume is estimated using the appropriate design rainfall depth, the catchment areas and other relevant input parameters. The storage zone is to be estimated using the Revised Universal Soil Loss Equation (RUSLE). The parameters that would be used to size the sediment basins are outlined in Table 7-1. These design parameters are aligned with the requirements detailed in the Soils and Construction Volume 1 and Volume 2D (Landcom, 2004 and DECC 2008).

Table 7-1 – Design criteria for the preliminary sizing of sediment basins

Parameter Value Comments

Rainfall Parameters

Rainfall depth duration (days) 2 and 5

5 day adopted as standard duration. 2 day to be adopted only when severe space constraints exist (not used for the concept design).

Rainfall percentile 80th and 85th 85th adopted for all sensitive receiving waterway environments with construction duration not exceeding 3 years. Refer to section 9.2.3.2 for the location of all the sensitive waterways.

Rainfall Depth (mm) – 5 Day

80th = 25.1 mm 85th = 32.0 mm

For Camden 85th has been used for all basins for the concept design (conservative for non-sensitive waterways).

Rainfall Depth (mm) – 2 Day

80th = 21.6 mm 85th = 29.2 mm

For Camden (not used for the concept design).



Parameter Value Comments

Rainfall Parameters Volumetric Runoff Coefficient, Cv

0.5 - 0.56 for 2 day 0.56 - 0.64 for 5 day

0.8 adopted for expected type of activities on site and compacted surfaces.

Rainfall intensity for 2 year ARI, 6 hr duration 9.47 mm/hr

For The Northern Road Used to derive to Rainfall Erosivity below. Source: Bureau of Meteorology

RUSLE Parameters

Soil/sediment Type C, D or F Varies along the route. Mainly Type F, Type D, and small localised pockets of Type C. Type D has been adopted for deeper subsoils as per the site specific soil test results in Appendix H

Erodibility, k 0.02 to 0.08 K=0.06 (high) adopted for all basins, as per the site specific soil test results in Appendix H.

Rainfall Erosivity, R 2012 For The Northern Road Based on site specific rainfall intensity.

Hydrologic Soil Group D High runoff potential assumed. Ref: Appendix F of Blue Book

Soil Cover, C 1 Corresponding to expected type of activities on site.

Soil Conservation Practices, P 1.3 Corresponding to expected type of activities on site.

Length Slope Factors, LS Variable 0.19 to 3.3

Determined separately for: 1. main road way; L=80m, and 2. steeper embankment areas (cut and fill), L=10m

Assumed V:H=1:2 Sediment Yield Time Period (months) 2 to 6 6 months adopted (conservative).

Using the above technical criteria, a simplified method to size sediment basins along the proposal has been derived which takes into account key elements of each catchment such as catchment area, steepness of longitudinal road slopes and the presence of steeper slopes of either cut or fill in the catchment.

Sediment basin volume per unit area rates were estimated using the Blue Book design methodology for a range of parameters described below. The results of this assessment are given in Table 7-2.

The three key design elements for sizing each sediment basin are:

Site catchment area contributing to sediment basins (excludes any diverted offsite runoff).

Longitudinal road slope of the catchment (generally flat is <1%, mild ranges between 1% to 5% and steep is >5%).



The percentage of the total contributing catchment area that is either “cut” or “fill”. These are batter/embankment areas that could be as high as 60% in some catchments, but are generally in the order of 15%. This parameter has been split into two categories for the purpose of a simplified basin sizing method, 15% representing a range of 0% to 30%, and 45% representing a range of 30% to 60%.

For the concept design the 85th percentile 5-day rainfall depth design parameter has been adopted for all sediment basins, not only at sensitive waterways locations. However Table 7-2 includes unit rates for the 80th percentile and a 2-day rainfall depth which may be used during the detailed design stages in some areas with severe space limitation constraints.

Table 7-2 – Site specific derived unit rates to size sediment basins for The Northern Road upgrade (m3/ha)

Longitudinal slope

Flat (<1%) Mild (1% to 5%) Steep (>5%)

% of contributing catchment in

Steep areas (Cut or Fill)

<30% >30% <30% >30% <30% >30%

Downstream waterways

sensitivity and %’ile for rainfall

depth

low 80%

high 85%

low 80%

high 85%

low 80%

high 85%

low 80%

high 85%

low 80%

high 85%

low 80%

high 85%

Estimated basin volume for 5-day

rainfall depth (m3/ha)

200 250 265 310 270 315 310 355 375 420 385 430

Estimated basin volume for 2-day

rainfall depth (m3/ha).

Not used for the concept design

125 160 185 220 190 225 235 270 300 330 310 340

7.1.2. Sediment basin design

This assessment has identified the preliminary locations and space requirements for the construction phase sediment basins to inform corridor width requirements for The Northern Road upgrade. The site topography is such that a very large number of basins would be required to treat every section of the construction area throughout all stages of the work. In order to minimise the number of sediment basins, and the impact of the construction of these basins on the local natural environment, the Blue Book criteria of “Minimum 150m3” of annual sediment loss has been



adopted. This criteria indicates that if the estimated annual soil losses from a disturbed catchment is less than 150m3, then a sediment basin may not be required subject to other erosion and sediment controls being implemented as described in the following two Blue Book extracts:

Reference: Blue Book Section 6.3.2, Clause (d): “.....the average annual soil loss from the total area of land disturbance can be estimated (Appendix A). Where this is less than 150 cubic metres per year, the building of a sediment retention basin can be considered unnecessary. In such circumstances, alternate measures may be employed to protect the receiving waters”

Reference: Blue Book, Appendix M, Clause (54): “Sediment basin(s) must be constructed where the calculated total annual soil loss from the disturbed lands is more than 150 cubic metres. Where the calculated basin size is less than 150 cubic metres, other erosion and sediment control devices can be installed instead”.

It was estimated that a contributing disturbed area exceeding 0.85 ha on this site would generate 150m3 of annual soil loss. Therefore for catchments less than approximately 0.85 ha, a sediment basin would not be proposed. This is approximately the equivalent of a surface area of 40m wide and 200m long. If 40m is assumed to be an average width of disturbance, then lengths of approximately less than 200m would not require a sediment basin. These dimensions are an approximation only and catchments widths and shape will vary. The required volume of each sediment basin with a catchment area larger than 0.85ha was determined according to the maximum catchment area that would drain to the basin during the various stages of the construction and the design parameters identified in Table 7-3.

The site specific soil test results (refer to Appendix H) indicated that the subsoils for this project are Type D soils (fine soil particles and dispersible) with moderate to high erodibility. Gypsum flocculation would be required for all proposed basins.

Preliminary locations and sizing of temporary sedimentation basins for the construction phase of The Northern Road upgrade are presented in Table 7-3.

The design and the location of the road have a significant effect on the size and location of the basins. Changes to the road design in the future may result in changes to basin locations or addition of new basins, resulting in an adjustment of the construction boundary identified for the proposed basins.

For a typical detail of the construction phase sediment basin, refer to drawing number NB11363-ECC-DG-2002 in the Drainage and Water Quality set of drawings. Temporary fencing would be required around all sediment basins for public safety.



Table 7-3 – Temporary sediment basins for the concept design of The Northern Road upgrade

Basin number

Chainage (m)

Side Right/Left

Basin name * Min basin volume required (m3)

1 800 L TB0.800L 1018 2 1325 L TB1.325L 1310 3 4500 R TB4.500R 285 4 4900 L TB4.900L 400 5 5400 L TB5.400L 425 6 6325 R TB6.325R 1350 7 6660 L TB6.600L 350 8 7275 L TB7.275L 685 9 8775 R TB8.775R* 680 10 7725 L TB7.725L 245 11 9100 L TB9.100L 670 12 9950 L TB9.950L 505 13 10575 L TB10.575L 570 14 10650 R TB10.650R 520 15 12250 R TB12.250R* 1180 16 13800 R TB.13800R 385 17 14975 R TB14.975R 450

Note: * Sediment basins to be converted to a permanent spill basin at the end of the construction phase

7.2. Operational phase

This section of the report focuses on the proposed water quality controls for the operational phase of the project. It provides a description of the potential water quality issues, water quality objectives, design criteria/strategy used, and the proposed water quality control measures.

7.2.1. Potential water quality issues

The project has the potential to affect existing local water quality due to the generation of additional pollutants directly attributable to the widened road and associated increased vehicle traffic in the future. The most important pollutants of concern relating to road runoff are:

Sediments from the paved surface from pavement wear and atmospheric deposition.

Heavy metals attached to particles washed off the paved surface.

Oil and grease and other hydrocarbon products.



The emphasis in stormwater quality management for road runoff is that of managing the export of suspended solids and associated contaminants – namely heavy metals, nutrients and organic compounds (Austroads, 2001). Pollutants such as nutrients, heavy metals and hydrocarbons are usually attached to fine sediments (RTA, 2003), therefore trapping suspended solids is the primary focus of the water quality management strategy for the operational phase of the project.

Though unlikely, the risk of accidental spillage of hazardous materials would always be present. Without satisfactory means of containment, the spillage of contaminants could pass rapidly into the drainage system and impact downstream ecosystems. Accidental spills of chemicals or petrol in accidents can cause severe damage to the ecology of waterways and therefore environmental protection would be required.

7.2.2. Water quality objectives

The water quality objective of the project is to minimise the potential impacts on downstream receiving waters so that the system changes the existing water regime by the smallest amount practicable. This objective is consistent with the RMS’s Water Policy 1997 (RTA, 1997) and Code of Practice for Water Management 1999 (RTA, 1999).

7.2.3. Proposed water quality controls

The potential impacts on water quality as a result of the upgrade are to be minimised by implementing adequate permanent water quality controls for the operational phase. For this project, it has been decided in consultation with RMS that water quality treatment would be provided through vegetated swales with rock check dams and spill management basins. Permanent water quality ponds would not be used.

7.2.3.1. Vegetated swales

Vegetated swales (table drains) are used to convey stormwater to the receiving waterways instead of pipes where possible and provide water quality treatment through the removal of suspended solids and their associated pollutants. Pollutant removal is facilitated by the interaction between the flow and the vegetation along the length of the swale. The vegetation and rock check dams act to spread and slow velocities, which in turn aids the deposition of sediments.

For a typical detail of the vegetated swale with rock check dams, refer to drawing number NB11363-ECC-DG-2005 in the Drainage and Water Quality set of drawings.

7.2.3.2. Spill management basins

A risk assessment has been undertaken to identify all the locations where a spill basin would be required. The assessment considered two key factors:



The improved traffic conditions.

The sensitivity of the downstream waterways.

The approach that has been discussed and agreed with RMS is that a spill basin will be provided for the concept design at selected locations based on a desktop risk assessment that takes into consideration two key criteria:

Sensitivity of receiving waterways, using aquatic habitat as an indicator, as assessed by the SKM aquatic ecologist.

A traffic risk assessment to identify the areas along the upgraded road that are likely to carry a “higher” risk of accidental spills.

Information on current crash statistics that were supplied by RMS were reviewed by the traffic engineer and considered in this risk assessment. The risk assessment then identified creek locations where spill basins would be required. For example, the Narellan Creek crossing would require spill basins to protect a sensitive waterway. If a chemical spill (such as hydrocarbons) occurred along this stretch of the road, the spill would be contained in a spill basin before it is transported into the creek.

The improved horizontal and vertical geometry of the upgrade and the improved layout of the signalised interchanges would reduce the current risk of accidental spills. The sensitive receiving waterways along the upgrade were assessed by the aquatic ecologist to determine which ones would be considered to be “sensitive”. The results of this assessment indicated that spill containment would be required at four locations:

Narellan Creek (sensitive waterway).

Lowes Creek (sensitive waterway).

Thompsons Creek (sensitive waterway).

Tributary of South Creek (higher risk of accidental spill at the Belmore Road interchange).

The spill containment basins which have an approximate volume of 60m3 are designed to capture liquid spills of a maximum 20,000L less dense than water via an under flow baffle arrangement. Following containment, the pollutant would be pumped out and the spill disposed of in an appropriate manner. The spill basins are designed to contain spills in dry weather or light to moderate rainfall events. The proposed spill basins for the proposal are listed in Table 7-4.



Table 7-4 – Spill containment permanent basins for the concept design of The Northern Road upgrade

Basin number

Chainage (m) Side Right/Left

Basin name * Receiving waterway

1 1050 L SB1.050L Narellan Creek 2 1200 L SB1.200L Narellan Creek 3 8775 R SB8.775R* Lowes Creek 4 9025 R SB9.025R Lowes Creek 5 10600 R SB10.600R South Creek tributary 6 12250 R SB12.250R* Thompson Creek 7 12350 R SB12.350R Thompson Creek

Note: * Spill basins to be converted from a sediment basin at the end of the construction phase

For a typical detail of the spill basin, refer to drawing number NB11363-ECC-DG-2003 in the Drainage and Water Quality set of drawings. High fencing would be required around all spill basins for public safety.

7.2.3.3. Access to spill basins

Access to proposed spill basins to allow for maintenance has been provided and indicated on plans. Accesses to basins off local roads and the interface of cut/fill batters on The Northern Road have been considered. The road boundary has been adjusted to suit the proposed access tracks and associated turning areas at the end of the track.

These access tracks will cross the proposed open drains at some locations and suitable crossings will need to be detailed at the detailed design stage.



8. Considerations for detailed design The following design considerations would need to be reviewed during the detailed design phase of The Northern Road upgrade:

Opportunities to retain any existing transverse drainage culverts should be assessed, particularly the existing culvert adjacent the Narellan Creek bridge.

The alignment of transverse culverts in order to reduce required transition works. For example, the alignment of culvert C5.35 could be optimised to reduce the extent of downstream channel works.

The three transverse culverts at Harrington Grove, C2.16, C2.45, and C2.65 between chainages 2000 and 2650, should be reviewed in coordination with the proposed adjacent urban development.

The design standard of culvert outlet protection measures should be reviewed and an appropriate standard adopted in consultation with RMS.

The requirement for Type A energy dissipaters should be reviewed at detailed design according to the specific site conditions at each location.

Adjustments to the design should be investigated where required to limit aquaplaning depths to a maximum of 4.0mm.

The pavement drainage design at the road cutting between chainage 2700 and 3000 should be reviewed to optimise the number of inlet pits and transverse pavement drainage lines.

Existing farm dam modification works would be further investigated and designed at the detailed design phase of the upgrade in consultation with landowners.



9. References Austroads (1994), Waterway Design: A Guide to the Hydraulic Design of Bridges, Culverts and Floodways, Austroads, Sydney.

Austroads (2000), Road Runoff and Drainage: Environmental Impacts and Management Options, 2000, Austroads, Sydney.

BOM (2003), The Estimation of Probable Maximum Precipitation in Australia: Generalised Short-Duration Method, Commonwealth Bureau of Meteorology.

DECC (2007), Practical Consideration of Climate Change Floodplain Risk Management Guideline, NSW Department of Environment and Climate Change, Sydney.

DECC (2008), Managing Urban Stormwater - Soils and Construction Volume 2D: Main Road Construction, NSW Department of Environment and Climate Change, Sydney.

FHWA (2006) Hydraulic Design of Energy Dissipators for Culverts and Channels: Hydraulic Engineering Circular Number 14, Third Edition, Federal Highway Administration.

IEAust (2001), Australian Rainfall and Runoff : A guide to flood estimation Volume 1, Institution of Engineers Australia.

LACE (2011), Initial Assessment of Drainage Requirements Volume 1 – Main Report, January 2011, Lyall & Associates Consulting Water Engineers, Sydney.

Landcom (2004), Managing Urban Stormwater: Soils and Construction Volume 1.

LMCE (1999), Upper Nepean River Tributary Flood Studies Volume 1 – Stages 1 and 2, Lyall and Macoun Consulting Engineers.

RTA (1993), Erosion and Sedimentation, Section 8 of Road Design Guide, Roads and Traffic Authority (RTA) of NSW: Sydney

RTA (1997), RMS Water Policy, Roads and Traffic Authority (RTA) of NSW: Sydney.

RTA (1999), RMS Code of Practice, Water Management, Roads and Traffic Authority (RTA) of NSW: Sydney.

RTA (2003), RMS Procedure for Selecting Treatment Strategies to Control Road Runoff, Roads and Traffic Authority (RTA) of NSW: Sydney.



Appendix A List of drawings



DRAWING NUMBER DRAWING TITLE

NB11363‐ECC‐DG‐2001 DRAINAGE NOTES

NB11363‐ECC‐DG‐2002 TYPICAL SEDIMENT BASIN DETAILS

NB11363‐ECC‐DG‐2003 TYPICAL SPILL BASIN DETAILS

NB11363‐ECC‐DG‐2004 TYPICAL BATTER CHUTE TO SPILL BASIN DETAILS

NB11363‐ECC‐DG‐2005 TYPICAL VEGETATED SWALE

NB11363‐ECC‐DG‐2006 DRAINAGE TYPICAL DETAILS SHEET 1






NB11363‐ECC‐DG‐2101 DRAINAGE PLAN SHEET 1 ‐ STN ‐100.0m TO 300.0m

NB11363‐ECC‐DG‐2102 DRAINAGE PLAN SHEET 2 ‐ STN 300.0m TO 800.0m























DRAWING NUMBER DRAWING TITLE


NB11363‐ECC‐DG‐2124 DRAINAGE PLAN SHEET 24 ‐ STN11200.0m TO 11750.0m










Appendix B Response to review comments



Appendix C Catchment areas and design flows

LACE (Existing) SKM (Existing) SKM (Design) LACE (Existing) LACE (Design) SKM (Existing) SKM (Design) * Comment on flows

The Northern Road 1080 X1 ‐ 2346 2324 2326 ‐ ‐ 195.0 195.0 196.3 196.5 ‐1170 X2 C1.17 32.2 35.7 35.5 ‐ ‐ 7.2 0.0 6.7 7.3 ‐1760 X3 ‐ 2.2 2 ‐ ‐ Catchment diverted to new culvert C1.39 0.8 0.9 0.6 0.0 ‐

2160 X4 C2.16 8.5 8.8 8.8 ‐ ‐ 2.5 3.2 2.3 3.11m3/s of existing flow bypasses to C2.45.

Design peak flow assumes future development without OSD

2430 X5 C2.45 24.7 14.7 14.3Difference due to delineation of boundary between

catchments to C2.45 and C2.65 ‐ 6.1 6.7 10.6 3.5 Existing flow includes bypass from C2.16 and C2.65

2650 X6 C2.65 33.6 43.8 43.5Difference due to delineation of boundary between

catchments to C2.45 and C2.65 ‐ 7.5 8.2 8.1 9.0 6.1m3/s of exisitng flow bypasses to C2.45

3100 X9 C3.10 7.2 8.8 8.8 SKM total area includes catchment of C2.95 ‐ 2.1 3.5 2.2 3.01.5m3/s of existing flow bypasses to C3.24.

Design peak flow assumes future development without OSD

3230 X10 ‐ 10.9 10.5 10.3 ‐ Design by others 3.0 3.9 4.0 2.8Existing flow includes bypass from C3.10

New culvert designed by others

3650 X12 ‐ 32.4 47.7 47.7SKM total area includes catchment of culvert under Peter

Brock Dr Design by others 7.2 11.7 9.3 10.3 Design by others

4520 X13 C4.52 18.6 16 15.6Minor difference in delineation of boundary between C4.52

and C4.65 ‐ 5.1 5.6 3.5 3.8 1.6m3/s of existing flow bypasses to C4.65

4650 X14 C4.65 19.3 21.5 21.1Minor difference in delineation of boundary between C4.52

and C4.65 ‐ 5.3 5.8 7.0 5.0 Existing flow includes bypass from C4.52 and C4.90

4870 X15 C4.90 19.2 18.4 21.7 ‐ Design of crossing receives additional catchment from C5.20 5.3 5.8 4.2 6.2Of existing catchment flow, 100year flow distributes approximately 0.8m3/s to C4.65, and

0.7m3/s over the exisitng road

5200 X16 C5.20 3.7 3.8 0.2 ‐

Majority of existing catchment diverted to C4.95 and C4.90. Design catchment is area between split carriageways drained by culvert under

southbound carriageway 1.3 1.5 1.1 0.1 Minor existing bypass of 0.06m3/s to C5.35

5350B X17 C5.35B 7.4 7.6 8.4 ‐Catchment for design case includes diverted portions from C5.20 and

C5.60 2.2 2.6 2.1 3.1Existing flow includes minor overflows from C5.20 and C5.60. Design peak flow assumes future development without OSD

5600 X18 ‐ 0.8 1 ‐ ‐Existing catchment diverted to adjacent catchments and to pavement

drainage 0.4 0.0 0.4 ‐Minor existing bypass of 0.05m3/s to C5.35.

5820 X19 ‐ 0.8 0.3 ‐ ‐Existing catchment partially removed by new road formation and residual

diverted to C6.10 0.4 0.0 0.1 ‐ ‐

6400 X21 C6.40 34.4 35.3 32.8 ‐ ‐ 7.7 8.4 6.7 6.9Of existing catchment flow, approximately2.7m3/s bypasses to C6.65, and 0.5m3/s overtops

road

6650 X22 C6.65 3.3 1.5 0.8SKM area excludes road pavement as road is in

superelevationExisting catchment diverted to adjacent catchments or to pavement

drainage 1.2 0.0 3.2 0.3 Existing flow includes bypass from C6.40

7440 X23 ‐ 2.6 0.8 ‐SKM area excludes road pavement as road is in

superelevation Existing catchment diverted to C7.75 1.0 0.0 0.3 0.0 catchment diverted to C7.75

7750 X24 C7.75 2 1.4 1.8SKM area excludes road pavement as road is in

superelevation ‐ 0.7 0.0 0.5 0.70.1m3/s of existing flow bypasses north into tributary of Lowes Creek.

Design peak flow assumes future development without OSD8900 X25 C8.95 1060 1080 1075.0 ‐ ‐ 128.0 141.0 114.0 125.0 Combined catchment flows9000 X26 C9.00 17.6 0 0.0 ‐ ‐ 0.0 0.0 0.0 0.0 09720 X27 C9.75 23.5 25.1 24.8 ‐ ‐ 5.8 6.3 5.5 5.9 ‐9870 X28 C9.87 12.7 12.2 10.7 ‐ Some of the existing catchment taken into pavement drainage 3.5 3.8 2.9 2.8 1.6 m3/s of existing flow overspills to C9.7510270 X29 ‐ 1.3 1.2 ‐ ‐ Catchment diverted to Belmore Road 0.6 0.0 0.2 ‐ ‐10610 X30 C10.61 161 160.6 159.0 ‐ ‐ 25.5 28.0 23.1 25.4 ‐11220 X33 ‐ 0.5 0.4 ‐ ‐ Catchment diverted north to C11.37 0.2 0.0 0.1 ‐ ‐11370 X34 C11.37 1.7 1.7 1.5 ‐ ‐ 0.7 0.9 0.5 0.7 Design peak flow assumes future development without OSD

12120 X36 ‐ 0.014 ‐ ‐Pavement drainage pipe to be removed. No hydrologic

assessment undertaken. ‐ 0.0 0.0 0.0 ‐ ‐12280 X37 ‐ 481 476.7 469.6 ‐ ‐ 52.6 58.3 59.3 58.4 ‐12610 X39 C12.61 3 5.6 6.5 Difference due to delineation of boundary ‐ 0.9 1.0 1.6 2.4 Design peak flow assumes future development without OSD

12620A X40 ‐ 1 ‐ ‐ ‐Catchment at intersection discharges directly to water course as Badgery's

Creek Road has a new alignment 0.4 0.0 0.0 ‐ ‐12620B X41 ‐ 1.5 ‐ ‐ ‐ 0 0.5 0.0 0.0 ‐ ‐12950 X42 C12.95 55 55.2 54.2 ‐ ‐ 9.2 10.2 10.0 11.0 ‐

13250 X43 C13.25 5.6 5.5 5.2 ‐ ‐ 1.5 1.9 1.6 2.10.2 m3/s overflows to adjacent catchment under existing conditions.

Design peak flow assumes future development without OSD13900 X45 C13.90 33.1 32.8 32.3 ‐ ‐ 6.3 6.9 6.3 7.0 ‐14200 X47 C14.20 8.2 8.3 8.0 ‐ ‐ 2.0 2.6 2.0 2.7 Design peak flow assumes future development without OSD14340 X48 C14.34 10.9 10.8 11.4 ‐ ‐ 2.5 2.8 2.6 3.2 ‐

14800 X49 ‐ 0.4 0.6 ‐ ‐Existing small catchment partially removed by new road formation and any

residual diverted north toward Badgery's Creek 0.2 ‐ 0.3 ‐ Residual catchment diverted north via table drain toward Badgery's Creek

Local Roads1390 Hillside Drive C1.39 ‐ ‐ 7.9 ‐ Local road not assessed by LACE ‐ ‐ ‐ 1.8 Design peak flow assumes future development without OSD2680 X7 (Cobbity Road West) ‐ 1 1.19 ‐ ‐ Catchment diverted to pavement drainage 0.6 0.0 0.4 ‐ Catchment diverted to pavement drainage2970 X8 (Cobbity Road East) C2.95 1.6 1.6 1.4 ‐ ‐ 0.6 0.0 0.5 0.7 Design peak flow assumes future development without OSD3580 X11 (Oran Park Link Road 1) ‐ 15.2 15.1 0.0 ‐ Design by others 4.2 4.6 3.5 ‐ Design by others4950 Oran Park Link Road 2 C4.95 0 0 15.8 ‐ Local road not considered by LACE ‐ ‐ ‐ 4.2 ‐6070 X20 (Marylands Link Road 1) C6.07 0.9 0.9 0.7 ‐ ‐ 0.4 0.0 0.3 0.3 ‐6100 Marylands Link Road 1 C6.10 0 23.5 24.5 ‐ Local road not assessed by LACE ‐ ‐ 5.0 5.5 ‐7250 Marylands Link Road 2 C7.25 ‐ 104.4 104.4 ‐ Local road not assessed by LACE ‐ ‐ 16.4 18.0 ‐9300 Lowes Creek Link Road C9.30 ‐ ‐ 7.9 ‐ Local road not assessed by LACE ‐ ‐ 0.0 2.7 Design peak flow assumes future development without OSD10380 Belmore Road C10.38 ‐ ‐ 3.3 ‐ Local road not assessed by LACE ‐ ‐ 0.0 1.3 Design peak flow assumes future development without OSD10390 Belmore Road C10.39 ‐ ‐ 2.6 ‐ Local road not assessed by LACE ‐ ‐ 0.0 1.1 Design peak flow assumes future development without OSD10800 X31 (Robinson Road) C10.80 5.1 8 7.6 ‐ ‐ 1.6 2.9 2.0 2.7 Design peak flow assumes future development without OSD10970 X32 (Loftus Road) C10.97 ‐ 2.4 2.2 ‐ Local road not assessed by LACE ‐ ‐ 0.8 0.9 Design peak flow assumes future development without OSD12050 X35 (Thames Road) C12.05 0.9 0.7 0.5 ‐ ‐ 0.3 0.0 0.3 0.3 Design peak flow assumes future development without OSD12350 X38 (Solway Road) C12.35 8.4 5.8 5.2 Difference due to delineation of boundary ‐ 2.1 0.0 1.6 1.9 Design peak flow assumes future development without OSD12680 Dart Road C12.68 ‐ ‐ 2.5 ‐ Local road not assessed by LACE ‐ ‐ 0.0 1.1 Design peak flow assumes future development without OSD13780 Proposed Derwent Road C13.76 ‐ ‐ 3.6 ‐ Local road not assessed by LACE ‐ ‐ 0.0 1.3 Design peak flow assumes future development without OSD13800 Proposed Derwent Road C13.88 ‐ ‐ 4.6 ‐ Local road not assessed by LACE ‐ ‐ 0.0 1.8 Design peak flow assumes future development without OSD

13920 X46 (Avon Road) C13.92 0.4 0.4 0.4 ‐ ‐ 0.2 ‐ 0.2 0.2Design for local road not assessed by LACE.

Design peak flow assumes future development without OSD14520 Severn Road C14.52 ‐ ‐ 0.4 ‐ Local road not assessed by LACE ‐ ‐ 0.0 0.2 Design peak flow assumes future development without OSD14600 Mersey Road C14.60 ‐ ‐ 2.1 ‐ Local road not assessed by LACE ‐ ‐ 0.0 0.9 Design peak flow assumes future development without OSD

* design flows allow for 10% increase of rainfall due to climate change and for catchments less than 10ha increased flows for impervious development without OSD

Catchment Reference (from LACE)

Design 100yr flow (m3/s)Design Road

Chainage (DRC)

Catchment Areas (ha)Comment on differences in catchment areas

(existing conditions)Comment on catchment areas (design conditions)

New Culvert ID (SKM)



Appendix D Hydraulic results for transverse drainage design

Existing Structure100 year ARI capacity with no

overflows (Yes / No)New Structure


US Invert

DS Invert

Length (m)

Grade (%)

Cross Catchment Overflow RL

Control Level On Road *

Existing ‐ no blockage

Design ‐ no blockage

Design ‐ 50% blockage

The Northern Road 1080 X1 4 span 40m long bridge Yes Duplicate existing bridge ‐ 73.5 72.0 72.0 72.01170 X2 2 x 3000 x 1500 RCBC Yes 2 x 3000 x 1500 RCBC C1.17 67.2 66.9 64.2 0.5 ‐ 73.5 72.0 72.0 72.01760 X3 1 x 900 x 600 RCBC No Remove existing culvert2160 X4 1 x 750 RCP No 4 x 1050 RCP C2.16 93.0 92.3 48.8 1.5 94.6 95.2 94.2 93.7 94.42430 X5 2 x 750 RCP No 1 x 2400 x 900 RCBC C2.45 90.4 89.2 51.2 2.5 ‐ 92.8 92.8 91.3 92.32650 X6 2 x 1500 x 600 RCBC No 3 x 1800 x 1200 RCBC C2.65 90.6 90.3 65.9 0.5 92.8 93.3 93.2 91.8 92.82680 X7 1 x 600 x 300 RCBC No Remove existing culvert3100 X9 1 x 600 RCP No 4 x 1050 RCP C3.10 92.5 91.5 59.3 1.6 94.0 96.2 93.6 93.2 93.93230 X10 3 x 675 RCP No Design by others3650 X12 3 x 1500 x 900 RCBC Yes Design by others4520 X13 3 x 600 RCP No 3 x 2100 x 900 RCBC C4.52 100.2 99.9 58.0 0.5 101.3 102.1 101.2 100.7 101.24650 X14 1 x 1050 RCP No 3 x 1800 x 900 RCBC C4.65 99.6 99.2 64.1 0.5 101.3 101.7 101.0 100.3 100.94870 X15 1 x 1050 RCP No 3 x 2100 x750 RCBC C4.90 101.2 100.1 63.2 1.7 102.7 103.4 102.2 101.9 102.65200 X16 2 x 525 RCP No 1 x 450 RCP C5.20 104.2 103.9 25.3 1.3 105.4 105.3 105.3 104.5 104.95350A X17 ‐ ‐ 3 x 1050 RCP C5.35A 104.0 103.7 25.0 1.2 107.2 106.9 105.2 104.9 106.05350B X17 2 x 450 RCP No 3 x 1050 RCP C5.35B 103.3 103.0 39.8 0.8 105.4 105.5 104.7 104.2 105.35600 X18 1 x 450 RCP No Remove existing culvert5820 X19 1 x 450 RCP Yes Remove existing culvert6400 X21 1 x 1800 x 900 RCBC No 5 x 1200 RCP C6.40 94.7 94.4 55.8 0.5 96.6 98.0 96.3 95.6 96.66650 X22 1 x 450 RCP No 2 x 450 RCP C6.65 94.0 93.7 22.3 1.5 ‐ 95.5 95.3 94.5 95.07440 X23 1 x 450 RCP No Remove existing culvert7750 X24 1 x 450 RCP No 2 x 750 RCP C7.75 82.0 81.4 58.3 1.0 83.5 84.0 83.6 82.5 83.18900 X25 3 x 3000 x 3000 RCBC No 8 x 2400 x 2100 RCBC C8.95 65.7 65.4 53.8 0.6 ‐ 69.3 68.8 67.9 68.69000 X26 4 x 600 RCP No 25 x 1800 x 900 RCBC C9.00 67.3 67.0 53.6 0.5 ‐ 69.9 68.8 67.9 68.69720 X27 1 x 2100 x 600 RCBC No 3 x 2400 x 900 RCBC C9.75 72.6 72.0 62.6 1.0 75.3 74.9 73.6 73.3 74.39870 X28 3 x 375 RCP No 4 x 2100 x 600 RCBC C9.87 73.9 73.4 54.9 0.9 75.3 76.1 74.3 74.3 74.910270 X29 1 x 375 RCP No Remove existing culvert10610 X30 3 x 1800 x 900 RCBC No 5 x 2100 x 1500 RCBC C10.61 69.8 69.5 52.8 0.6 ‐ 73.2 71.3 71.2 72.411220 X33 1 x 375 RCP Yes Remove existing culvert11370 X34 1 x 375 RCP No 3 x 600 RCP C11.37 86.6 86.0 54.2 1.0 ‐ 88.6 87.5 87.0 87.512120 X36 1 x 450 RCP ‐ Remove existing culvert12280 X37 2 span bridge Yes Duplicate existing bridge ‐ 72.7 71.5 71.4 ‐12610 X39 1 x 900 RCP No 3 x 900 RCP C12.61 75.6 74.5 56.5 2.0 76.8 77.6 75.2 75.2 76.112620A X40 1 x 525 RCP ‐ Remove existing culvert12620B X41 1 x 525 RCP ‐ Remove existing culvert12950 X42 2 x 1350 RCP No 3 x 1800 RCP C12.95 76.4 76.0 69.6 0.5 79.6 81.4 78.6 77.7 79.213250 X43 2 x 525 RCP No 5 x 825 RCP C13.25 87.8 86.3 54.0 2.7 89.0 89.7 88.5 88.3 88.913900 X45 1 x 4200 x 600 RCBC Yes 7 x 1800 x 600 RCBC C13.90 88.4 86.8 62.0 2.6 ‐ 90.8 88.9 88.9 89.314200 X47 2 x 525 RCP No 2 x 900 RCP C14.20 84.2 84.0 54.5 0.5 87.2 87.6 87.0 85.7 87.514340 X48 2 x 750 RCP No 3 x 1500 x 600 RCBC C14.34 85.8 85.5 54.7 0.5 87.2 88.1 87.0 86.4 87.014800 X49 1 x 525 RCP No Remove existing culvert

Local Roads1390 Hillside Drive ‐ ‐ 2 x 900 RCP C1.39 74.4 73.2 60.5 2.0 ‐ 76.4 ‐ 75.2 76.12680 X7 (Cobbity Road West) 1 x 600 x 300 RCBC No Remove existing culvert2970 X8 (Cobbity Road East) 1 x 750 x 350 RCBC No 2 x 600 RCP C2.95 93.5 93.4 39.1 0.5 ‐ 95.0 94.3 94.1 94.93580 X11 (Oran Park Link Road 1) 1 x 375 RCP ‐ Design by others4950 Oran Park Link Road 2 ‐ ‐ 3 x 1500 x 750 RCBC C4.95 102.9 101.9 56.7 1.8 ‐ 104.7 ‐ 103.6 104.26070 X20 (Marylands Link Road 1) 1 x 450 RCP No 1 x 600 RCP C6.07 105.3 105.0 56.4 0.5 ‐ 107.8 106.5 105.8 106.46100 Marylands Link Road 1 ‐ ‐ 4 x 1200 RCP C6.10 100.5 99.9 45.3 1.3 ‐ 102.7 102.6 101.4 102.47250 Marylands Link Road 2 ‐ ‐ 4 x 2400 x 1500 RCBC C7.25 81.6 81.3 41.1 0.6 ‐ 84.0 84.3 82.7 83.79300 Lowes Creek Link Road ‐ ‐ 5 x 750 RCP C9.30 70.8 70.5 57.4 0.5 ‐ 72.4 ‐ 71.5 72.310380 Belmore Road ‐ ‐ 3 x 600 RCP C10.38 81.5 80.4 26.2 4.5 84.9 83.9 ‐ 82.2 83.310390 Belmore Road ‐ ‐ 2 x 750 RCP C10.39 78.5 77.6 43.6 2.1 ‐ 80.1 ‐ 79.1 80.010800 X31 (Robinson Road) 1 x 375 RCP No 5 x 750 RCP C10.80 73.0 72.8 44.7 0.5 ‐ 74.7 74.6 73.7 74.610970 X32 (Loftus Road) 1 x 450 RCP No 3 x 600 RCP C10.97 80.2 79.7 28.3 1.8 ‐ 81.7 ‐ 80.7 81.312050 X35 (Thames Road) 1 x 375 RCP No 3 x 450 RCP C12.05 72.2 72.0 30.3 0.5 ‐ 73.4 73.6 72.5 72.812350 X38 (Solway Road) 1 x 750 RCP No 4 x 900 RCP C12.35 70.7 70.6 23.5 0.6 ‐ 72.4 72.2 71.2 71.812680 Dart Road ‐ ‐ 2 x 750 RCP C12.68 77.3 77.2 33.2 0.5 ‐ 80.7 ‐ 78.0 78.813780 Proposed Derwent Road ‐ ‐ 4 x 750 RCP C13.76 92.0 90.5 52.6 2.8 ‐ 93.6 ‐ 92.5 93.013800 Proposed Derwent Road ‐ ‐ 4 x 750 RCP C13.88 88.9 88.7 36.5 0.5 ‐ 90.5 ‐ 89.5 90.113920 X46 (Avon Road) 1 x 450 RCP Yes 2 x 525 RCP C13.92 88.8 88.6 22.4 0.5 ‐ 90.8 89.1 89.0 89.314520 Severn Road ‐ ‐ 1 x 600 RCP C14.52 84.9 84.5 22.6 1.8 ‐ 86.3 ‐ 85.3 85.714600 Mersey Road ‐ ‐ 3 x 750 RCP C14.60 85.0 84.3 35.8 2.1 ‐ 87.1 ‐ 85.5 86.0

* Minimum road level is kerb invert at road sag

Control Level ‐ Design 100 yr ARI Upstream Water Levels Design Road

Chainage (DRC)Catchment Reference (from

LACE)

Existing Cross Drainage Concept Design



Appendix E Design of outlet protection works

Design Road Chainage (DRC)


100 year ARI Outlet Velocity (m/s)

Froude Number

Outlet ProtectionOverall

Length (m)End Width

(m)

1170 C1.17 3.6 1.1 Rock Apron 6 101390 C1.39 3.6 2.2 Type A Energy Dissipater 9 82160 C2.16 3.1 1.9 Type A Energy Dissipater 8 102430 C2.45 4.5 2.5 Type A Energy Dissipater 9 92650 C2.65 1.4 0.4 Rock Apron 5 92970 C2.95 1.8 1.0 Rock Apron 3 43100 C3.10 3.2 2.1 Type A Energy Dissipater 9 103230 C3.24 ‐ ‐ Design by others3650 C3.65 ‐ ‐ Design by others4520 C4.52 2.1 1.2 Rock Apron 4 94650 C4.65 2.3 1.2 Rock Apron 4 84870 C4.90 3.6 2.2 Type A Energy Dissipater 16 104950 C4.95 3.4 2.1 Type A Energy Dissipater 13 95200 C5.20 1.9 1.6 Type A Energy Dissipater 5 25350A C5.35A 3.0 1.6 Type A Energy Dissipater 7 75350B C5.35B 3.0 1.6 Type A Energy Dissipater 7 76070 C6.07 1.8 1.0 Rock Apron 3 36100 C6.10 3.3 1.8 Type A Energy Dissipater 12 116400 C6.40 2.4 1.1 Rock Apron 3 136650 C6.65 2.1 1.7 Type A Energy Dissipater 3 37250 C7.25 3.2 0.4 Rock Apron 6 147750 C7.75 2.2 1.6 Type A Energy Dissipater 5 58900 C8.95 1.7 0.4 Rock Apron 9 259000 C9.00 1.4 0.4 Rock Apron 4 489300 C9.30 2.0 1.0 Rock Apron 3 99720 C9.75 2.9 1.8 Type A Energy Dissipater 14 129870 C9.87 2.0 1.6 Type A Energy Dissipater 9 1210380 C10.38 4.0 2.9 Type A Energy Dissipater 8 510390 C10.39 3.2 2.2 Type A Energy Dissipater 8 510610 C10.61 3.3 1.2 Rock Apron 6 1510800 C10.80 2.0 1.0 Rock Apron 3 910970 C10.97 2.6 2.0 Type A Energy Dissipater 6 511370 C11.37 2.0 1.5 Type A Energy Dissipater 3 512050 C12.05 1.3 1.0 Rock Apron 2 412350 C12.35 1.9 1.2 Rock Apron 4 812610 C12.61 3.5 2.2 Type A Energy Dissipater 9 912680 C12.68 1.9 1.0 Rock Apron 3 512950 C12.95 3.1 1.2 Rock Apron 9 1413250 C13.25 3.3 2.6 Type A Energy Dissipater 8 913780 C13.76 3.2 2.6 Type A Energy Dissipater 6 813800 C13.88 1.9 1.0 Rock Apron 3 713900 C13.90 3.3 2.6 Type A Energy Dissipater 11 1713920 C13.92 1.3 1.1 Rock Apron 3 214200 C14.20 2.1 0.6 Rock Apron 4 514340 C14.34 2.1 1.2 Rock Apron 3 714520 C14.52 2.4 2.0 Type A Energy Dissipater 5 314600 C14.60 2.8 2.3 Type A Energy Dissipater 6 6



Appendix F Assessment of peak flows

PEAK FLOW RATE ASSESSMENT‐ SECTION 1

10YR 20YR 100YR 10YR 20YR 100YR 10YR 20YR 100YR 10YR 20YR 100YRC1.17 Existing Culvert Size: 2 x 3000 x 1500 RCBC

The existing culvert is located about 85m north of the Narellan Creek Bridge. It discharges into an existing watercourse that joins Narellan Creek approximately 150m downstream of the existing culvert outlet. The nearest existing dwelling adjacent Narellan Creek is about 550m downstream of the culvert.

4.233 5.47 9.385 1.323 1.413 1.663 Proposed Culvert Size: 2 x 3000 x 1500 RCBC

The proposed culvert is at the same location as the existing culvert and will discharge into the existing watercourse.

4.698 5.975 9.762 1.358 1.448 1.703 Minor increase in peak flow and velocity will have minimal impact on peak flood levels and velocity in the downstream watercourse.

Culvert location and inlet/outlet discharge points consistent with LACE.

C1.39 Existing Culvert Size: none

Catchment runoff captured by small open drain to the west of an existing access track. The open drain flows south towards the outlet of the existing culvert at chainage 1170.

0.478 0.579 0.994 1.083 1.133 1.256 Proposed Culvert Size: 2 x 900 dia. RCP

Culvert discharges to the watercourse at the outlet of C1.17. Channel from the outlet of this culvert to the oult of C1.17 has designed for the 100 year ARI peak flow to avoid adverse impact to the adjoining property.

0.992 1.206 1.898 1.836 1.955 2.212 Increase in peak flow and velocity has been mitigated by designing downstream channel to the 100 yr peak flow and velocity.


C2.16 Existing Culvert Size: 750 dia RCP

The existing culvert discharges into a natural watercourse. Flow in the downstream channel is governed by the existing culvert capacity and upstream diversion to adjacent culvert. An existing farm dam is located on the downstream watercourse approximately 80m from the existing culvert outlet. There are no existing dwellings adjacent the watercourse at risk of flooding.


The proposed culvert is located at the same location as the existing and will discharge into the same existing watercourse.

1.863 2.255 3.413 1.202 1.261 1.395 Increase in peak flow and velocity as a result of the upgraded road and culvert, however no existing dwellings at risk.


C2.45 Existing Culvert Size: 2 x 750 dia RCP

The existing culvert discharges into a natural watercourse. Flow in the downstream watercourse is influenced by upstream overflows received from adjacent culverts to the south and north. There are no existing farm dams or dwellings at risk of flooding in the immediate vicinity of the culvert.

4.771 6.784 12.562 0.727 0.806 0.96 Proposed Culvert Size: 2400 x 900 RCBC

The proposed culvert is located immediately adjacent the existing adn will discharge into the existing watercourse. The invert levels match existing ground surface levels so no channel works will be required.

1.933 2.475 3.987 0.549 0.594 0.688 Reduction in peak flow and velocity in the downstream channel due to the increased capacity of adjacent culverts.


C2.65 Existing Culvert Size: 2 x 1500 x 600 RCBC

The existing culvert discharges into a natural watercourse. Flow in the downstream channel is governed by the existing culvert capacity and upstream diversion to adjacent culvert. There are now existing farm dams or dwellings at risk of flooding in the immediate vicinity of the culvert.


The proposed culvert is at the same location as the existing culvert but with additional skew to match the downstream watercourse. The downstream invert is about 700mm below the natural ground surface. Downstream channel works are required to realign the existing watercourse due to encroachment from the widened road embankment. Approximately 70m of creek realignment is proposed.

4.752 6.058 9.963 1.067 1.145 1.31 Significant Increase in peak flow and velocity at the outlet of this culvert as a result of the upgraded road and culvert, however the peak flow in the water course within the private property will be the combined effect of runoff from C2.65 and C2.45 and will not be signficant. There are no exisitng dwelling adjacent to the water course, therefore, not impacted by the upgrade.


C2.95 Existing Culvert Size: 750 x 300 RCBC

Existing culvert located under a local road that discharges into a table drain adjacent the existing road within the road corridor. The table drain runs to the inlet of an existing culvert under TNR at chainage 3100.

0.293 0.374 0.607 0.491 0.526 0.596 Proposed Culvert Size: 2 x 600 dia RCP

The proposed culvert is located approx 12m east of the existing as the proposed road widening will encroach on the location of the existing culvert and downstream table drain. The downstream invert of the proposed culvert is about 1.4m below the natural surface level. A new trapezoidal channel is proposed to carry flow from the outlet of C2.95 to the inlet of C3.10.

0.381 0.459 0.69 0.459 0.486 0.549 Small increase in peak flow and velocity in the downstream channel. Channel has been located within the road corridor and sized for the 100 yr peak flow, thereby mitigating any potential flood impact to adjacent property.

LACE did not provide any culvert at this location due to lack of road design data and suggested that culvert is required at this location which should be sized to cater for future development upstream of the catchment.


The existing culvert discharges into a natural drainage line that joins a natural watercourse 190m downstream of the culvert outlet. There is an existing farm dam approx 100m from the culvert outlet. Flow in the downstream channel is governed by the existing culvert capacity, as overflows discharge to the adjacent culvert at chainage 3,240. The nearest existing dwelling is about 340m from the culvert outlet.


The proposed culvert is at the same location as the existing, however skewed to match the natrual drainage line depression. The downstream invert matches the natural ground surface level. No downstream channel works are proposed.


Also, It should be noted that there will be no impact on down stream flows as the flows from culverts C3.24 and C3.10 combine 160m downstream as in the existing situation with C3.24 having reduction in peak flows.



The existing culvert discharges into a natural watercourse. Flow in the downstream channel is governed by the existing culvert capacity and upstream diversion to the adjacent culvert at chainage 4,650. A catchment external to TNR also contributes runoff to the channel immediately downstream. There is a series of existing farm dams on the watercourse starting about 95m from the culvert outlet.


The proposed culvert is located adjacent the existing and skewed to match the upstream and downstream low points. The downstream invert is 0.8m below the natural ground surface. Downtream channel proposed to transition to natural surface level.


Also, It should be noted that there will be no significant impact on down stream flows as the flows from culverts C4.52and C4.65 combine at the dam within the private property with C4.65 having reduction in peak flows.


CULVERT EXISTING DRAINAGE SITUATION PROPOSED DRAINAGE DIFFERENCE BETWEEN LACE AND

SKM DESIGNFLOW VELOCITY ‐ EXISTING FLOW VELOCITY ‐ PROPOSED

DOWNSTREAM IMPACTPEAK FLOW RATES ‐ EXISTING PEAK FLOW RATES ‐ PROPOSED


10YR 20YR 100YR 10YR 20YR 100YR 10YR 20YR 100YR 10YR 20YR 100YRCULVERT EXISTING DRAINAGE SITUATION PROPOSED DRAINAGE

DIFFERENCE BETWEEN LACE AND SKM DESIGN

FLOW VELOCITY ‐ EXISTING FLOW VELOCITY ‐ PROPOSEDDOWNSTREAM IMPACT

PEAK FLOW RATES ‐ EXISTING PEAK FLOW RATES ‐ PROPOSED


The existing culvert discharges into a natural watercourse. Flow in the downstream watercourse is influenced by upstream overflows received from adjacent culverts to the south and north. There are a series of existing farms dams on the downstream watercourse starting about 65m from the culvert outlet. There is also an existing structure 120m north east of the culvert outlet.


The proposed culvert is located 25m north of the existing culvert. The downtream invert is 0.3m below the natural ground surface level. Downstream channel proposed to transition to natrual surface level.

2.628 3.374 5.541 0.563 0.599 0.673 Reduction in peak flow and velocity in the downstream channel due to the increased capacity of the adjacent culverts.



The existing culvert discharges into a natural watercourse. Flow in the downstream channel is governed by the existing culvert capacity and upstream diversion to the adjacent culvert at chainage 4,650. There is a series of existing farm dams on the watercourse starting about 190m from the culvert outlet. There is also an existing structure 90m north east of the culvert outlet that is adjacent the downstream channel.


The proposed culvert is at the same location as the existing and discharges to the same downstream watercourse. The downstream invert matches the natural ground surface level and the culvert outlet discharges to the existing water course/depression.

3.278 4.148 6.523 1.073 1.141 1.209 Increase in peak flow and velocity due to upstream catchment diversion and increased pavement drainage catchment. The 100r ARI peak flood level in the downstream channel is estimated to increase about 80mm. The increased flood level would remain below the ground level at the existing structure by about 100mm so would not cause inundation of the structure.

LACE design provides downstream channel of the culvert along the toe of the raod batter in Oran Park Link Rod 2 the culvert is skewed to allow for this.

SKM design consists of aligning the channel straight across the TNR and discharge to the exising depression.


The existing channel is a natural watercourse that leads to the inlet of the existing culvert at chainage 4,900.


The proposed culvert is located under the Oran Park Link Road 2. The outlet of the proposed culvert is 60m from the inlet of C4.90. The downtstream invert is 0.3m below the natural ground surface level. A downstream channel located within the road boundary is proposed to carry concentrated flow from the outlet of C4.95 to the inlet of C4.90.

2.311 2.972 4.769 0.97 1.065 1.265 Increase in peak flow and velocity due to diversion of upstream catchment and increased capacity of downstream culvert. Downstream channel has been designed for the 100yr peak flow and velocity.



The existing culvert discharges into a natural drainage line that joins a natural watercourse 180m from the culvert outlet. Flow in the downstream channel during larger events is controlled by the culvert capacity as overflows will travel north to the adjacent existing culvert at chainage 5,350. There are no existing farm dams or adjacent dwellings along the reach of the downstream receiving channel.

0.636 0.816 1.319 0.957 1.029 0.977 Proposed Culvert Size: 450 dia RCP

The proposed culvert is at the same location as the existing and will discharge into the same receiving channel. The downstream invert is at the natural ground surface level. No downstream channel works required.

0.095 0.12 0.189 0.518 0.566 0.651 Reduction in peak flow and velocity due to diversion of upstream catchment.



The existing culvert discharges into an existing downstream watercourse. The existing culvert and downstream watercourse receive some minor overflows from adjacent upstream catchments during larger events. There are no existing farm dams or adjacent properties along the reach of the downstream watercourse.


The proposed culvert will be located next to the existing culvert and will discharge into the same receiving watercourse. The downstream invert closely matches the natural ground surface level. Downstream channel provided to transition from the new culvert outlet to the alignment of the existing watercourse.

1.844 2.232 3.332 1.079 1.104 0.749 Minor increase in peak flow and velocity due to upstream catchment diversion at the outlet of C5.35.However, combined effect of runoff through C5.35 and C5.20 would be that peak flow within the water course in the property would not be significant. No existing dwellings at risk.

LACE design provides downstream channel of the culvert along the toe of the road batter in Oran Park Link Rod 3 the culvert is skewed to allow for this.

SKM design consists of aligning the channel straight across the TNR and discharge to the exising water course.

P5.60 Existing Culvert Size: 450 dia RCP

The exisitng culvert discharges into the upper reach of an existing watercourse. Flow in the downstream channel during larger events is controlled by the culvert capacity as overflows will travel south to the adjacent existing culvert at chainage 5,350. There is an existing farm dam on the downstream watercourse 330m from the culvert outlet.

0.253 0.323 0.517 0.399 0.419 0.461 Proposed Culvert Size: 600 dia RCP

The proposed pavement drainage outlet is about 20m norht of the existing culvert and will discharge into the same receiving watercourse. No downstream channel works will be required.

0.171 0.212 0.33 0.381 0.391 0.419 Minor reduction due to diversion of upstream catchment. No adverse impact to downstream.

LACE advised that no cross drainage is required at this location.

P5.82 Existing Culvert Size: 450 dia RCP

The existing culvert discharges east into the upper reach of an existing watercourse. Flow in the downstream channel during larger events would be controlled by the culvert capacity as overflows will travel north along TNR towards the outlet of the existing culvert at chainage 6,070.

0.124 0.16 0.262 0.655 0.697 0.784 Proposed 450 dia RCP pavement drainage outlet

The proposed pavement drainage outlet will discharge into the same receiving watercourse. A length of channel from the pavement drainage outlet will direct flow to the receiving watercourse.

0.105 0.136 0.222 0.622 0.671 0.753 Minor reduction in peak flows as a result of TNR upgrade. No adverse impact to downstream property.

LACE did not provide pavement drainage outlet at this location.


The existing culvert is located at chainage 6,070 and discharges west under TNR.

0 0 0.027 0 0 0.453 Proposed Culvert Size: 600 dia RCP

The proposed culvert is located under the local road and discharges north along TNR towards the outlet of C6.40. The culvert downstream invert is about 1.8m below the natural surface level. A downstream channel is proposed that extends adjacent TNR for 220m and discharges to an existing table drain on the eastern side of the existing TNR.

0.237 0.287 0.431 0.43 0.453 0.509 Increase in peak flow and velocity due to diversion of catchment. Downstream channel proposed within the road boundary and has been designed for the 100yr peak flow and velocity to discharge to outlet of culvert C6.40.







C6.10 Existing Culvert Size: assumed no culvert under the access

The exisitng watercourse is crossed by a property access. The size of the culvert under the access is unknown. The downstream watercourse discharges into an existing farm dam about 50m from the access road. Spill from the farm dam then travels to the inlet of an existing culvert under TNR at chainage 6,400.


The proposed culvert is located at the existing watercourse. The culvert downstream invert is approx 1.2m below natural ground level. A downstream channel is required to transition to the natural ground surface level and discharge into the existing farm dam.

2.668 3.458 6.022 0.575 0.633 0.569 Minor increase in downstream peak flow and velocity. No existing dwellings at risk.

Culvert location and inlet/outlet discharge points consistent with LACE. However, SKM design consists of straight culvert across the road due to constructon issue, whreas, LACE culvert is skewed to align with the downstream water course.

C6.40 Existing Culvert Size: 1800 x 900 RCBC

The existing culvert discharges into a downstream natural watercourse. Flow in the downsream watercourse is controlled by the culvert capacity as overflow travels north towards the inlet of the culvert at chainage 6,650. There is an existing farm dam about 75m from the culvert outlet, but no existing dwellings.

3.055 3.355 4.702 0.456 0.471 0.522 Proposed Culvert Size: 5 x 1200 RCP

The proposed culvert is at the same location as the existing culvert and discharges into the same watercourse. The culvert downstream invert matches the natural ground level. No downstream channel works will be required.

3.666 4.79 8.267 0.486 0.534 0.628 Increase in peak flow and velocity due to increased capacity of the culvert. No existing dwellings at risk, therefore, no downstream channel works to contain the increased peak flow in 100 year ARI has been considered. The increase in the 100yr flow downstream will cause a 50mm increase in the 100yr flow depth over the existing dam wall (increasing from 0.11m to 0.16m). This is considered acceptable and no works to the existing dam wall are proposed.

Downstream of the existing dam, the peak flow rate will not increase signficantly due to runoff from C6.65 arriving downstream of the dam with reduced peak flow rate.

Culvert location and outlet discharge points are consistent with LACE. However, the inlet arrangement adopted by SKM is different from LACE . SKM have considered the existing dam and channel from spill way of the dam considering how inflow would get into the culvert rather than schematic open drains along toe of batter shown in LACE design.


The exisitng culvert discharges into a receiving drainage channel that enters a natural watercourse 190m from the culvert outlet. Existing downstream channel flows are impacted by overflows from the existing culvert at chainage 6,400. There are no existing farm dams or dwellings adjacent the downstream channel reach at risk of flooding.


The proposed culvert is at the same location as the existing culvert and will discharge into the same receiving channel. The culvert downstream invert is about 0.3m below the natural surface level. Downstream channel works are proposed to transition to the natural ground level.

0.219 0.278 0.439 0.685 0.74 0.848 Reduction due to diversion of upstream catchment and increased capacity of adjacent culvert. No adverse impact to the downstream property.

LAC E did not provide culvert at this location. SKM have provided the culvert to drain the proposed TNR median. The proposed culvert outlet discharges to the existing discharge point.


The existing natural watercourse is crossed by an existing property access, which forms the wall of an existing farm dam. Catchment runoff would enter the downstream channel by spilling over the access. There are no existing farm dams or dwellings adjacent the downstream reach at risk of flooding.


The proposed culvert is located at the existing watercourse. The culvert downstream invert is about 0.7m below the natural ground surface level. Downstream channel works are required to transition to the natural ground level.

8.661 11.205 18.744 0.632 0.684 0.715 Negligible increase in peak flow and velocity. No adverse impact to downstream property.

LACE did not provide any culvert at this location due to lack of road design data in Marylands Link Road 2. SKM has provided this culvert as the proposed Maryland Link Road 2 crosses the existing water course at this location.

P7.30 Existing twin hydraulic structures about 90m apart under property access crossing tributary of Lowes Creek.

The existing watercourse is a tributary of Lowes Creek that is crossed by an existing property access. There is another access track about 320m downstream followed by a major water storage dam. There are no existing dwellings adjacent the watercourse along this reach.

17.84 23.054 37.608 0.544 0.577 0.606 Pavement drainage via an open channel on the northern side of Marylands Link Road 2.

The proposed pavement drainage will discharge into the watercourse on the downstream (northern) side of the existing access track structures. The additional pavement drainage catchment and a reduction in the access roads upstream catchment causes a small net increase in the total catchment area draining to this point.

18.017 23.284 37.982 0.545 0.578 0.606 Negligible increase in downstream peak flow and velocity at the point of discharge and no existing dwellings at risk.

Marylands Link Road 2 pavement drainage catchment and discharge point not considered in LACE assessment.


The existing culvert discharges into a downstream natural drainage channel. The drainage line discharges to an existing natural watercourse and farm dam 270m from the culvert outlet. There are no existing dwellings at risk of flooding between the culvert outlet and farm dam.


The proposed culvert is at the same location as the existing culvert and will discharge into the same receiving drainage channel. The culvert downstream invert matches the natural ground surface level. No downstream channel works required.

0.758 0.912 1.549 0.423 0.443 0.49 Minor increase in peak flow and velocity due to increased pavement drainage catchment. No existing dwellings at risk. Downstream water course is a wide natural depression currently caters for the existing culvert runoff. Channel work to cater for increase in peak flow is not required.

LACE did not provide any culvert at this location. SKM has provided this culvert as at the location of the existing culvert.

Notes:1 Flow rates calculated at downstream road boundary and is calculated by PRM method.2 Flow depth and velocities have been calculated from SKM's in‐house software 'CDMD' and calculated at downstream road boundary.3 Above design and calculation are based on survey information available to the concept design stage and may change subject to detailed survey.d Existing dam location is approximate and is based on aerial photo.5 Exisitng water course location is approximate and is taken from 'Hydroline' layer in NSW Department of Land GIS map and also from survey information at concept design stage.6 Climate change factor has been applied to both existing and design situations.7 Downstream channel is designed for 100 year ARI with minimum freeboard not less than the existing at the road boundary.


10YR 20YR 100YR 10YR 20YR 100YR 10YR 20YR 100YR 10YR 20YR 100YRC8.95 Existing Culvert Size: 3x3300x3000 RCBC

The existing culvert discharges into water course ‐ Lowes Creek.

Proposed Culvert Size: 8x2400x2100 RCBC

Proposed culvert is located approx 50m north of the existing culvert. Refer to design report for details on

flows and downstream impact and flooding for this location


C9.05 Existing Culvert size : 4x600 dia Proposed culvert size: 25x1800x900RCBC

Proposed culvert is located at the location of the exisitng culvert.

Refer to design report for details on flows and downstream impact and flooding for this location


C9.30 Existing Culvert Size: N/A

There is no culvert in the present condition at this location. Runoff is captured by a channel running along the side of the road.

N/A N/A N/A N/A N/A Proposed Culvert Size: 5x750 dia RCP

The proposed culvert is under the new Lowes Creek Link Road. This culvert discharges into the proposed trapezoidal channel running along the toe of the batter on the western side of TNR. This channel then discharges into the culvert C9.05. The existing dam will require filling or adjustments to allow for the construction of this channel.

There are no existing houses in close proximity to this culvert.

0.172 0.207 0.31 1.731 1.817 2.005 Culvert down stream channel has been design for 100 year ARI to avoid adverse impact to adjoining property and discharges to inlet of culvert C9.05.


C9.75 Exisitng Culvert Size: 2100x600 RCBC

The existing culvert is located at approximate chainage 9725 which discharges to existing natural watercourse. The culvert receives overflow from the culvert immediately north at chainage 9870. This water course runs through the private property fronting TNR and discharges into the existing dam within the property. The existing house on the property is located approximately 50m SE of the culvert downstream headwall. There are a number of existing dams which the water course passes through further downstream of this dam.

Based on the available survey information, the 100yr flow is contained within the watercourse and accordingly, the existing house is flood free.

3.611 4.723 7.727 2.294 2.375 2.502 Proposed Culvert Size: 3x2400x900 RCBC

The proposed culvert is located at the same location as existing. However, it has been skewed to discharge into the existing water course.

Tailout channel work is required due to the fact that the proposed culvert outlet invert is approximately 0.8 m below the exisitng ground level. Tail out channel has been designed for 100 year ARI and flow depth not more than the exisitng .The channel works will be required to the proposed road boundary. Easement is not required.The flowrate has been calculated and the flow is contained within the proposed tail out channel. Downstream of the tail out channel, the flow will be contained within the existing watercourse.

3 3.828 6.331 2.205 2.414 2.882 Design peak flow rate is less than existing as no overflows will be received from culvert C9.87. Flow velocities also do not increase significantly, therefore there will be no adverse impacts in relation to flooding and scour.

However, channel work may be required to extend to the exisitng dam in the detail design stage subject to detail survey.

The upgrade will cause a small 3% increase in the combined peak 100yr flow from culverts C9.75 and C9.87. This impact will diminish downstream of TNR as additional catchment areas enter the watercourse.

LACE suggested a stright culvert across TNR at this location instead of skewed one proposed by SKM. SKM design also considers inlet channel to the culvert intaking runoff from the exisitng dam after modification to its spillway.

C9.87 Existing Culvert Size: 3x375 dia The existing culvert is located at approximate chainage 9870 and discharges into a channel going through the property on the eastern side of TNR and eventually into the existing dam. Flow in the downstream channel in controlled by the capacity of the existing culvert as overflow travels south to the culvert at chainage 9725. There is no existing watercourse line downstream of this culvert and the discharge from this culvert appears to flood the driveway of the property. However, this cannot be confirmed due to the lack of detailed survey.

The house on th property is located approximately 60m East of the downstream the culvert headwall and it is likely that the exist houses and other structures might be impacted by the culvert outflows.


The proposed culvert is approximaely 10m north of the existing culvert. It discharges into a channel that goes around the house in the existing property and eventually into the existing dam which would have minimal impact to the frontage of the property. Easement is required for this channel.

Another option of connecting this channel to the tail out channel of C9.75 approximately 110m south which discharges into the existing water course line was also assessed. However, this would require the channel to be constructed in front of the house which may not be acceptable to the property owner. A culvert of the same size as the proposed culvert under TNR would also be required under the driveway and these works would have significant impact on the property. Therefore, this option has not been implemented. However, this could be considered at detailed design stage after the negotiation with the property owner.

1.572 2.02 3.287 1.507 1.66 1.999 Flows downstream will approximately double mainly due to the new culverts increased capacity. The proposed downstream channel through the property has been designed for 100 year ARI ensuring that flow is contained within the channel and therefore will have no flooding impacts to the property. The design velocity is less than the existing and as such will not have any scour issues.

The upgrade will cause a small 3% increase in the combined peak 100yr flow from culverts C9.75 and C9.87. This impact will diminish downstream of TNR as additional catchment areas enter the watercourse.

LACE also suggested the culvert at the location suggested by SKM. However, downstream channel for the culvert has been shown to run along the toe of the road batter and discharge to outlet of the culvert C9.75.

P10.00 The existing drainage element is a table drain adjacent Carrignton Road that drains in an easterly direction. The table drain captures runoff from properties to the north and the existing Carrington Road pavement.

0.795 1.03 1.706 N/A N/A N/A The proposed upgrade of TNR and the Carrington Road tie in works will require a new table drain adjacent Carrington Road. The new table drain will connect to the existing drainage system. There will be a small increase in the catchment area draining to the table drain as a result of the upgrade.

0.8 1.033 1.725 N/A N/A N/A There will be a minor 1% increase in the design peak flows at the proposed discharge point. This would have minimal impact on flooding to existing downstream properties.

Discharge point was not included in the LACE assessment.

CULVERT EXISTING DRAINAGE SITUATION PROPOSED DRAINAGE DIFFERENCE BETWEEN LACE AND

SKM DESIGNFLOW VELOCITY ‐ EXISTING FLOW VELOCITY ‐ PROPOSED

DOWNSTREAM IMPACTPEAK FLOW RATES ‐ EXISTING PEAK FLOW RATES ‐ PROPOSED






C10.61 Existing Culvert Size: 2x1800x900 RCBC

The existing culvert is located at approximate chainage 10575 and discharges into the existing water course 20m downstream. This watercourse runs along a slightly vegetated area. Due to the lack of detailed survey in this area, it cannot be determined if the area downstream is flooded.

House on the adjacent property is approximately 80m east of the downstream headwall.


The proposed culvert is approximately 20m west of the existing culvert. Tail out channel works is required as the downstream end of the culvert is approximately 0.7m below the ground. The tail out channel extends to the existing dam 80m north of the downstream HW which eventually discharges to the exsiting water course 20m downstream of the dam. An easement is required to extend the proposed channel to the existing dam.

12.812 16.531 27.432 2.625 2.846 3.286 There will not be increase in the peak flow rates.The propopsed down stream channel has been designed ensuring that the flood level is less than the existing for 100yr ARI. However, this is based on current survey information and needs to be confirmed at detailed design stage when detailed survey information is available.

LACE provided the culvert skewed to the road alignment and matched the oultet to the exising outlet and did not require downstream channel works. SKM design provides culvert at approx 30m north of the existing culvert and is aligned straight under the TN requiring significant down stream channel works.

C10.39 Exisitng Culvert Size: N/A

Under the existing conditions, there is no need for a culvert. Runoff is captured in the channel running along the southern side of TNR as well as the dam located at Ch 10575. Both the channel and dam discharge into the culvert at Ch 10600.

N/A N/A N/A N/A N/A N/A Proposed Culvert Size: 2x750 dia RCP

The proposed culvert is under Belmore Road west of TNR. This new culvert discharges into an open drain on the north of Belmore Road running along the toe of batter of TNR. This channel eventually discharges into C10.61. There are no exsiting houses in close proximity to this culvert.

0.634 0.766 1.155 2.695 2.833 3.144 The channel downstream of the culvert has been designed for 100 year ARI and does not impact adversly on the adjoining property.


C10.38 Existing Culvert Size: Information not available from the current survey

it appears that there is an exisitng culvert located under Belmore Road at this location. It discharges into the the existing watercourse immediately downstream. There are no existing houses in close proximity to this culvert.

N/A N/A N/A N/A N/A N/A Proposed Culvert Size: 3x600 RCP

The proposed culvert is located appoximately 10m west of the existing culvert. Tail out channel works is required for this culvert to direct flows to the existing water course.

There are no properties in close proximity to this culvert.

0.718 0.873 1.31 3.264 3.445 3.751 The culvert discharges to the existing natural water course which is of sufficent capacity to cater for the flows.


C10.80 Existing Culvert Size: 375 dia RCP, 450 dia RCP

The existing culvert is located at Robinson Road on the east of TNR. This culvert discharges into a well formed open channel which connects to the existing water course line at Ch 10600. Assessment of this channel shows that 100yr flow from this culvert is contained within it.

There are no properties in close proximity to the downstream end of this culvert.

1.051 1.353 2.242 2.378 2.378 2.483 Proposed Culvert Size: 5x750 dia RCP

The proposed culvert is located approximately 20m north east of the existing. A tail out channel is required for this culvert as the downstream invert is 1m below existing ground level. This tail out channel connects to a propopsed trapezoidal open channel which eventually connects to the existing water course at Ch 10600.

There are no existing houses in close proximity to the downstream end of this culvert.

1.513 1.826 2.734 1.66 1.744 1.943 The culvert downstream channel has been sized for 100 year ARI to ensure that there will be no adverse impact on the adjoining property.


C10.97 Existing Culvert Size: Information not available

The existing culvert is located at Loftus Road west of TNR. This culvert discharges to a channel which eventually discharges to the culvert at Ch 10600.

Assessment of the tail out channel downstream shows that it overtops in the 100yr event and flows through the property and eventually into the dam at Ch 10750.

0.412 0.53 0.885 N/A N/A N/A Proposed Culvert Size: 3x600 dia RCP

The proposed culvert is approximately 20m downstream of the existing. The downstream invert of the culvert is around 0.65m below the exsiting ground. The tail out channel diverts flow into culvert C10.61 and eventually to the exsiting water course.

There are a number of properties downstream of this culvert, the closest being approximately 25m from the downstream HW and around 5m from the edge of the downstream trapezoidal channel.

0.497 0.608 0.906 2.413 2.508 2.77 There is minor increase in peak flow rates. Assessment of existing condition shows the current channel is insufficient to carry flow from the culvert for 100 yr ARI. The proposed channel has been assessed for its capacity and the 100year flow is contained within it and therefore poses no risk of flooding the property.


C11.37 Existing Culvert Size: 2x375 RCP

The outlet for the existing culvert is located Ch 11375 and discharges to a channel located approximately 5m from the private property which then flows into the existing dam. Based on available survey information, the 100yr flow is contained within the channel and the property remains flood free.

0.324 0.415 0.678 2.283 2.313 2.341 Proposed Culvert Size: 3x600 RCP

The proposed culvert is located appoximately 10m south of the existing. The downstream headwall is 10m from the exsiting property.

The culvert will discharge into the existing drainage line and dam. Flow from this dam then follows the natural ground to discharge into the existing watercourse approximately 140m south of this dam.

0.549 0.667 1.003 1.716 1.821 2.031 There wil be an increase in peak flow rates and flood level which will be accomodated in the existing channel and will not impact on the existing property.



The existing culvert runs under Thames Road. This culvert discharges into an open channel which runs along the toe of road batter and eventually Thompsons Creek at Ch 12275. 100yr ARI flow is contained within the channel.

Exisitng dwelling in the property is approximately 60m west from the downstream headwall of the culvert.


The proposed culvert is located approximately 15m west of the existing. This culvert discharges into a proposed trapezoidal channel which eventually discharges in to Thompsons Creek at Ch 12275.

Existing property is approximately 40m west of the downstream headwall of the culvert. From the trapezoidal channel, the existing property at Ch 12125 is approximately 30m.

0.188 0.228 0.249 1.062 1.119 1.269 No significant changes in peak flow rates. Proposed down stream channel has been sized such that the flow is contained within the channel and therefore will have no flooding impacts to the property.








The existing culvert runs under Solway Road near the intersection with TNR. This culvert is skewed and discharges into a well formed open channel running along the toe of the batter and eventually into Thompsons Creek at Ch 12275. 100yr flow is contained within the channel.

The existing house on adjoing proprety downstream of the culvert is approximately 50m south of the downstream HW.


The proposed culvert is approximately 20m south of the existing. A tail out channel is required as the invert level of this culvert is approximately 1m below existing ground. This tail out channel discharges into Thompsons Creek at Ch 12275.

The existing house on adjoining property is approximately 10m from the downstream HW and the tail out channel is 7m. The downstream channel runs through the frontage of the property and but does not impact adversly in relation to flooding..

1.064 1.284 1.922 1.623 1.709 1.911 There has been minor increase in peak flow rates. The propopsed down stream channel has been designed such that the 100yr flow is contained within the channel and will have no flooding impacts to the property.Existing access to the property is from Solway Road, therefore, property access is not impacted by the works.



The existing culvert is located at Ch 12600. It discharges into a channel that flows through the downstream property. The house at this private property is located approximately 35m north east of the downstream HW. Pavement drainage from the roundabout also discharges into this channel which finally discharges into the existing dam. No survey information available in relation to drainage infrastructure downstream of the dam under Lea Road.

Preliminary assessment of this channel with the available survey information for the 100yr flow indicates that it has insufficient capacity and therefore floods the property. However, this can only be confirmed with detailed survey.


The proposed culvert is located approximately 25m north east from the existing. The downstream invert level is 0.2m below existing ground. This culvert discharges into the proposed tailout channel which eventually discharges into the existing dam which is 80m downstream of the outlet HW. An easement for this channel has been proposed.

Exisitng house on the property is approximately 60m north east of the outlet headwall and 45m from the channel.

1.413 1.717 2.572 2.118 2.232 2.479 Significant increase in peak flow rates has occured due to additinal pavement drainage catchments . Downstream channel throgh the private property has been designed to ensure that the flow is contained within the channel and therefore will have no flooding impacts to the property.

However, no assessment of drainage downstream of the existing dam has been carried out due to lack of detailed survey information and it is believed that this would be carried out as part of the detailed design.


C12.68 Existing Culvert Size: None

There is no culvert at this location under existing condition. Runoff is captured in the dam at Ch 12650 which discharges into the culvert at Ch 12600.


The proposed culvert is the proposed relocated section of Dart Road. The tail out channel for this culvert discharges into the trapezoidal channel leading into culvert C12.61 and eventually into exisitng dam at Ch 12575 on the northern side of TNR. Existing house on the property next to this channle is approximately 10m from the edge of the tail out channel.

1.207 1.491 2.333 1.644 1.733 1.925 The propopsed down stream channel has been designed such that the flow is contained within the channel and therefore will have no flooding impacts to the property.


C12.95 Existing Culvert Size: 2x1375 dia RCP

The existing culvert tail out channel discharges into a dam located approximately 25m downstream of the outlet headwall. The dam eventually discharges into the existing water course approximately 30m north.

There is a house/shed on the existing property approximately 60m north east of the tail out channel.


The proposed culvert is at the same location as existing. Tail out channel is required for this culvert as there is an obstruction in the flow path around 20m downstream of the headwall. The proposed tail out channel discharges into the existing water course.

5.615 7.209 11.945 2.294 2.462 2.809 No Significant increase or decrease in peak flow rates. No adverse impact to the downstream property is envisaged..


C13.25 Existing Culvert Size: 2x0.525 dia RCP

The existing culvert discharges into a dam approximately 30m downstream of the outlet headwall. This dam then discharges into the existing water course.

There are two properties with existing houses on either side of the channel. Dwelling on property on the south east is approximately 85m and on the south west is approximately 80m away.

Based on the available survey, 100 year flow contained within the tail out channel and the water course.


The proposed culvert is at the same location as the exisitng. However, the proposed culvert is slightly skewed. The downstream IL of the culvert is approximately 0.5m below existing ground and therefore, a tail out channel is required. This channel discharges into the existing dam 20 downstream of the headwall which eventually discharges into the existing water course.

Assessment of flow through the proposed tail out channel and the water course has been carried out and it is found that the there will be no adverse impacts to the property.

Inlet channel work is required due to the requirement to relocate the spillway of the dam.

1.422 1.72 2.597 3.563 2.973 3.349 Significant increase in peak flow rate has occurred. However, an assessment of the propopsed down stream channel and water course shows that the flow is contained within the channel/water course and there will be no flooding impacts to the property.

The 100yr flood level over the downstream dam spillway will increase about 40mm due to the increased flows (from RL 85.7 to RL 85.74). The existing dwelling 30m south of the dam is at a RL of 88.0m and will therfore not be affected.

Culvert location and inlet/outlet discharge points consistent with LACE, however, the proposed culvert is straight compared to skew indicated in LACE design.

C13.76 Existing Culvert Size:Details of exisitng culvert not available

It appears that there is a culvert under the property access which outlets into a channel and eventually into the dam at Ch 13850. This dam discharges into the culvert at Ch 13900.

There is a dwelling within the adjoining property approximately 40m north of the existing dam.


The proposed culvert is located on the southern side of Derwent Road and is skewed. Downstream IL of this culvert is approximately 0.2m below existing ground. The tail out channel discharges into the the existing dam at Ch 13850 and eventually into proposed culvert C13.90.

0.773 0.939 1.41 2.128 2.253 2.531 The proposed downstream channel is within the road boundary and sized such that the flow does not impact adversly on the adjoining property.







C13.88 Existing Culvert Size: N/A N/A N/A N/A N/A N/A N/A Proposed Culvert Size: 4x750 dia RCP

The proposed culvert is located on the northern side of the relocated Derwent Road. The downstream IL is approximately 0.85m below existing ground. The tailout channel discharges into the existing water course, no easement is proposed.

There is a property approximately 75m north west of the downstream HW.

1.29 1.568 2.346 1.602 1.685 1.868 There will be increase in peak flow rate, however, the down stream channel and water course are of sufficient capacity and that there will be no adverse flooding impacts to the property.


C13.90 Existing Culvert Size: 4200x600 RCBC

The existing culvert discharges to the existing natural water course that runs through private properties. Houses/sheds on the existing property could have been affected by flow in the water course. However, this could not be confirmed due to the lack to detailed survey.


The proposed culvert is located at the same location as the existing but with skew. The culvert outlet is directed towards the existing water course. Tailout channel is required and designed with sufficient capacity so as not to flood the adjoining property.

3.721 4.761 7.833 0.822 0.873 0.989 Minor increase in peak flow rates. No adverse impacts envisaged.



Existing culvert is located at Avon Road and dischargses into a channel that goes around the dam and discharges into the culvert at Ch 13875.


The proposed culvert is located approximately 15m west of the existing. It discharges into a proposed tail out channel within the road boundary which eventually discharges into C13.90. The existing dam will require adjustment/filling to allow construction of this tailout channel.

0.159 0.194 0.29 1.143 1.229 1.377 Significant ncrease in peak flow rates occur , however, no dwelling/property would be adversly impacted.



The existing culvert discharges into the dam approximately 130m downstream of the headwall. This dam forms part of the existing water course line.

There is a house on the existing property approximately 75m north west of the downstream HW and another house approximatley 60m east of the downstream HW on the next adjoining property.

Assessment of the current ground conditions shows that the houses are flooded unde the 100 year ARI.


The proposed culvert is located at the same location as the existing but is slightly skewed. The discharges to the existing dam approximately 100m downstream of the outlet HW through the tail out channel going through the property at 1520 The Northern Road, Bringelly. This channel runs along the western fence of the property and has been sized for 100 year capacity to ensure that there is no adverse flooding impact. Drainage easement will be required on the private property.

1.939 2.34 3.686 1.736 1.928 2.196 Significant increase in peak flow rates has occurred due to flow diversion from adjacent culvert C14.34. However, the downstream channel has been designed with a capacity not to cause any adverse impact to downstream flood..



The existing culvert is located at approximately Ch 14325 and discharges into the existing watercourse which flows past through the exisitng property on the nothern side of TNR to the existing dam located approximately 180m north of the downstream HW.

There is a property with a house and what appears to be a shed in the flow path. Assessment of the survey shows that the 100yr flow is not contained within the channel and floods the property.


The proposed culvert is approximately 10m north west of the existing. This culvert discharges into the existing water course. There is an existing house and other structuress that are in close proximity to the water course.

1.67 2.159 3.516 1.991 2.06 2.116 There wil be a minor increase in peak flow rates and flood level. This will be accomodated in the existing watercourse.

Culvert location and inlet/outlet discharge points consistent with LACE. However, LACE have proposed an easement for downstream channel on only one property that would require 90 degree bend to the channel before discharge to the existing dam.


There is no culvert at the present at Severn Road. Runoff is carried east along this local road and discharged into the existing water course at approximate Ch 14225 which flows past the existing property at 30 Severn Road.

N/A N/A N/A N/A N/A N/A Proposed Culvert Size: 600 dia RCP

Mersey Road and Severn Road junction has been relocated approximately 70m north of the existing junction. The proposed culvert is located under Severn Road and discharges into existing dam located 25m downstream.

0.112 0.137 0.267 2.08 2.204 2.427 The downstream tail out channel has been sized to ensure that therefore will be no flooding impacts to the adjoining property property.

No culvert proposed at this location in LACE design.SKM design required a culvert due to proposed intersection configuration at this location.


There is no culvert at the present under Mersey Road at this location. Runoff is carried east past the existing property at 10 Severn Road into the dam. This dam then dischanges into the existing water course at approximate Ch 14425.


This culvert discharges into a tail out channel which leads to an exisitng dam approximately 40m downstream of the proposed HW. The dam then discharges into the existing water crossing at approximate Ch 14225. There is a house in the existing property 10m downstream of the HW and the tail out channel has been modelled to avoid it. However, it should be noted that this property is within the project boundary.

0.483 0.591 0.881 2.239 2.378 2.683 Pre and post developed catchment seems to be similar at this location therefore it is envisaged that there will not be signficant increase in peak flow rates. The downstream channel has been sized to ensure that there is no adverse flooding impact on the adjoining property.


Notes:1 Flow rates calculated at downstream road boundary and is calculated by PRM method.2 Flow depth and velocities have been calculated from SKM's in‐house software 'CDMD' and calculated at downstream road boundary.3 Above design and calculation are based on survey information available to the concept design stage and may change subject to detailed survey.4 Existing dam location is approximate and is based on aerial photo.5 Exisitng water course location is approximate and is taken from 'Hydroline' layer in NSW Department of Land GIS map and also from survey information at concept design stage.6 Climate change factor has been applied to both existing and design situations.7 Downstream channel is designed for 100 year ARI with minimum freeboard not less than the existing at the road boundary.



Appendix G Aquaplaning checks

AQUAPLANING CHECKS- SECTION 1 (4-LANE DESIGN)Location Allow Length of Flow Path Rainfall

Depth Flow Path Slope Intensity Txt 0.30 mm Txt 0.40 mm Txt 0.50 mm Txt 0.60 mm Txt 0.90 mm Txt 1.20 mmmm (m) (%) (mm/hr) (mm) (mm) (mm) (mm) (mm) (mm)

580 NB 4 44 3.40 50.00 2.46 2.45 2.42 2.38 2.21 2.01600 SB 4 56 3.48 50.00 2.73 2.73 2.70 2.67 2.52 2.331380 NB 4 38.5 3.78 50.00 2.19 2.17 2.13 2.09 1.91 1.701380 SB 4 35.9 4.31 50.00 1.99 1.96 1.92 1.87 1.68 1.461390 WB 4 31.8 1.69 50.00 2.91 2.92 2.90 2.87 2.73 2.541420 SB 4 58.4 3.81 50.00 2.67 2.67 2.64 2.61 2.45 2.261600 SB 4 103.7 5.57 50.00 2.94 2.94 2.93 2.90 2.76 2.572000 SB 4 50 1.64 50.00 3.66 3.69 3.69 3.67 3.57 3.412660 WB 4 41.9 1.93 50.00 3.12 3.13 3.12 3.10 2.96 2.792680 WB 4 51.8 1.43 50.00 3.96 3.99 4.00 3.99 3.90 3.763500 SB 4 44.5 1.65 50.00 3.45 3.47 3.47 3.45 3.33 3.173700 NB 4 57.3 2.26 50.00 3.37 3.39 3.38 3.36 3.24 3.074920 WB 4 92.5 2.98 50.00 3.71 3.74 3.74 3.73 3.63 3.474940 EB 4 94.5 3.79 50.00 3.36 3.38 3.37 3.35 3.23 3.064960 EB 4 74.1 4.72 50.00 2.71 2.70 2.68 2.65 2.49 2.305100 NB 4 39.5 1.13 50.00 3.89 3.92 3.93 3.92 3.83 3.685440 EB 4 52.5 3.80 50.00 2.54 2.53 2.50 2.46 2.30 2.115840 SB 4 52.1 2.07 50.00 3.35 3.37 3.36 3.34 3.22 3.056060 WB 4 82 4.29 50.00 2.97 2.97 2.96 2.93 2.79 2.616050 WB 4 48.9 3.98 50.00 2.40 2.39 2.36 2.32 2.15 1.956050 EB 4 48.1 2.11 50.00 3.20 3.22 3.21 3.18 3.05 2.886060 NB 4 75.1 4.07 50.00 2.92 2.92 2.91 2.87 2.73 2.556300 SB 4 76.4 3.57 50.00 3.13 3.14 3.12 3.10 2.97 2.796300 NB 4 60 2.22 50.00 3.47 3.49 3.49 3.47 3.36 3.196800 NB 4 44.6 1.43 50.00 3.69 3.72 3.72 3.71 3.60 3.456840 SB 4 36.7 0.92 50.00 4.12 4.17 4.18 4.17 4.03 3.957130 SB w 66.5 2.63 50.00 3.37 3.39 3.38 3.36 3.24 3.077200 SB 4 41.4 4.27 50.00 2.14 2.12 2.08 2.03 1.85 1.647220 EB 4 85.4 3.27 50.00 3.43 3.45 3.44 3.42 3.31 3.147240 EB 4 51.4 3.78 50.00 2.52 2.51 2.48 2.44 2.28 2.087240 WB 4 58.2 3.82 50.00 2.66 2.66 2.63 2.60 2.44 2.257260 NB 4 62 2.46 50.00 3.36 3.38 3.37 3.35 3.23 3.077640 SB 4 20.2 0.64 50.00 3.68 3.71 3.71 3.70 3.60 3.447920 SB 4 43.9 1.36 50.00 3.75 3.78 3.78 3.77 3.67 3.517600NB 4 44.9 1.22 50.00 3.98 4.02 4.03 4.02 3.93 3.797280NB 4 35.7 1.72 50.00 3.06 3.07 3.05 3.02 2.89 2.712880SB 4 45.9 1.50 50.00 3.66 3.68 3.69 3.67 3.57 3.41

Flow Depth, d (mm). Texas Method

Max Flow Depth (mm)



180 NB 4 82.6 3.43 50.00 3.30 3.32 3.31 3.29 3.17 3.00570 WB 4 16.8 3.51 50.00 1.50 1.46 1.40 1.34 1.13 0.89580 NB 4 34.4 2.97 50.00 2.33 2.31 2.28 2.23 2.06 1.86590 WB 4 17.3 1.58 50.00 2.25 2.23 2.20 2.15 1.98 1.77580 WB 4 19.6 0.90 50.00 3.11 3.12 3.10 3.08 2.94 2.77600 NB 4 38 3.24 50.00 2.34 2.33 2.29 2.25 2.08 1.88600 SB 4 29.4 3.62 50.00 1.96 1.93 1.89 1.84 1.65 1.43620 SB 4 51.4 3.04 50.00 2.79 2.79 2.77 2.74 2.59 2.401380 NB 4 59.8 2.04 50.00 3.60 3.63 3.63 3.61 3.51 3.351380 SB 4 42.3 4.19 50.00 2.18 2.16 2.13 2.08 1.90 1.691390 WB 4 24.3 1.85 50.00 2.46 2.45 2.42 2.38 2.21 2.011400 WB 4 33.4 2.13 50.00 2.68 2.68 2.65 2.62 2.46 2.271420 SB 4 63.4 3.92 50.00 2.74 2.74 2.71 2.68 2.53 2.341600 SB 4 121 5.45 50.00 3.20 3.21 3.20 3.17 3.04 2.872000 SB 4 55.5 1.47 50.00 4.04 4.08 4.09 4.08 4.00 3.852660 NB 4 42.8 1.74 50.00 3.31 3.33 3.32 3.30 3.18 3.012670 NB 4 46.1 1.50 50.00 3.67 3.69 3.70 3.68 3.58 3.422700 NB 4 42 1.79 50.00 3.24 3.25 3.24 3.22 3.09 2.922880 SB 4 51.3 1.33 50.00 4.07 4.11 4.12 4.11 4.03 3.882960 SB 4 27.9 2.73 50.00 2.19 2.17 2.13 2.08 1.91 1.702970 SB 4 29.1 2.69 50.00 2.25 2.23 2.19 2.15 1.97 1.773500 SB 4 56.9 1.43 50.00 3.92 3.95 3.96 3.95 3.86 3.713680 NB 4 66.4 2.09 50.00 3.74 3.77 3.77 3.76 3.66 3.514920 SB 4 64.6 3.51 50.00 2.91 2.91 2.89 2.86 2.72 2.544920 WB 4 29.7 2.82 50.00 2.22 2.20 2.16 2.12 1.94 1.734940 EB 4 92.3 3.74 50.00 3.35 3.36 3.36 3.33 3.21 3.054940 WB 4 85.5 3.05 50.00 3.54 3.57 3.56 3.55 3.44 3.284960 WB 4 20.6 1.70 50.00 2.36 2.35 2.32 2.28 2.11 1.904960 EB 4 67 4.70 50.00 2.58 2.58 2.55 2.51 2.35 2.165090 NB 4 49.3 1.45 50.00 3.84 3.88 3.88 3.87 3.77 3.635170 NB 4 19.9 1.23 50.00 2.71 2.70 2.68 2.65 2.49 2.305440 SB 4 64.6 3.70 50.00 2.84 2.84 2.82 2.79 2.64 2.465830 SB 4 64.4 2.23 50.00 3.58 3.60 3.60 3.58 3.47 3.316050 WB 4 48.5 3.86 50.00 2.43 2.41 2.38 2.34 2.18 1.986050 NB 4 81.3 4.29 50.00 2.96 2.96 2.94 2.91 2.77 2.596050 EB 4 42.6 2.09 50.00 3.04 3.05 3.03 3.00 2.87 2.696060 NB 4 76.6 4.12 50.00 2.93 2.93 2.92 2.89 2.75 2.566080 EB 4 24.1 3.05 50.00 1.93 1.90 1.86 1.80 1.61 1.396280 SB 4 87.5 3.41 50.00 3.40 3.42 3.42 3.40 3.28 3.116300 NB 4 71.2 2.28 50.00 3.72 3.74 3.75 3.73 3.63 3.486780 SB 4 18.8 1.18 50.00 2.68 2.68 2.65 2.62 2.46 2.276800 NB 4 51.1 1.50 50.00 3.85 3.88 3.89 3.88 3.78 3.636840 SB 4 39.5 1.37 50.00 3.56 3.58 3.58 3.57 3.46 3.307140 SB 4 71.9 2.25 50.00 3.75 3.78 3.78 3.77 3.67 3.517220 WB 4 54.2 3.16 50.00 2.81 2.81 2.79 2.76 2.61 2.427220 EB 4 83.6 3.23 50.00 3.41 3.43 3.43 3.41 3.29 3.127240 SB 4 56.6 2.56 50.00 3.16 3.17 3.16 3.13 3.00 2.837240 WB 4 43.5 4.03 50.00 2.26 2.24 2.20 2.16 1.98 1.787270 NB 4 27.5 2.37 50.00 2.32 2.30 2.27 2.23 2.06 1.857570 SB 4 14.7 0.62 50.00 3.21 3.22 3.21 3.19 3.06 2.897610 NB 4 41.5 1.24 50.00 3.81 3.84 3.85 3.83 3.74 3.597640 SB 4 ‐0.5 ‐0.24 50.00 3.58 3.60 3.60 3.58 3.47 3.317650 SB 4 14.3 1.64 50.00 2.01 1.99 1.95 1.89 1.71 1.497660 NB 4 6.5 0.53 50.00 2.34 2.33 2.29 2.25 2.08 1.887920 SB 4 43.4 1.21 50.00 3.93 3.96 3.97 3.96 3.87 3.72


Max Flow Depth (mm)



8080 WB 4 56 3.55 50.00 2.70 2.70 2.68 2.64 2.49 2.308100 NB 4 56.4 3.93 50.00 2.59 2.58 2.55 2.52 2.36 2.168080 SB 4 74.4 3.94 50.00 2.95 2.95 2.94 2.91 2.77 2.588980 NB 4 43.5 1.34 50.00 3.76 3.79 3.79 3.78 3.68 3.539260 EB 4 101.8 3.07 50.00 3.83 3.86 3.87 3.86 3.76 3.619280 EB 4 79.5 3.12 50.00 3.39 3.41 3.40 3.38 3.26 3.109400 NB 4 51.5 3.29 50.00 2.69 2.69 2.66 2.63 2.48 2.2810000 EB 4 35.8 3.48 50.00 2.20 2.18 2.14 2.10 1.92 1.7110020 NB 4 67.5 2.58 50.00 3.42 3.44 3.44 3.42 3.30 3.1310360 NB 4 79.2 3.65 50.00 3.15 3.16 3.15 3.12 2.99 2.8210380 EB 4 59.2 4.98 50.00 2.37 2.35 2.32 2.28 2.11 1.9110460 NB 4 86.8 3.54 50.00 3.33 3.35 3.34 3.32 3.20 3.0310800 SB 4 32.4 2.64 50.00 2.39 2.37 2.34 2.30 2.13 1.9310980 NB 4 41.9 5.14 50.00 1.97 1.94 1.90 1.85 1.66 1.4511400 SB 4 41.9 1.25 50.00 3.81 3.84 3.85 3.83 3.74 3.5911480 WB 4 121.1 4.17 50.00 3.61 3.64 3.64 3.62 3.52 3.3611500 WB 4 117.2 4.22 50.00 3.54 3.56 3.56 3.54 3.43 3.2711840 SB 4 63.2 2.90 50.00 3.15 3.16 3.14 3.12 2.99 2.8112020 NB 4 28.7 2.63 50.00 2.26 2.24 2.20 2.16 1.98 1.7812360 NB 4 31.3 4.30 50.00 1.86 1.83 1.78 1.73 1.54 1.3112360 SB 4 57.3 5.86 50.00 2.16 2.14 2.10 2.05 1.87 1.6612680 SB 4 44.8 2.74 50.00 2.74 2.74 2.72 2.69 2.53 2.3512680 NB 4 57.3 2.12 50.00 3.47 3.49 3.49 3.47 3.35 3.1912700 EB 4 39.3 3.74 50.00 2.22 2.21 2.17 2.12 1.95 1.7412700 WB 4 28.9 2.59 50.00 2.28 2.27 2.23 2.19 2.01 1.8112710 WB 4 27.6 1.25 50.00 3.13 3.14 3.13 3.10 2.97 2.8012720 EB 4 70.5 3.23 50.00 3.15 3.16 3.15 3.12 2.99 2.8212720 NB 4 43.6 2.64 50.00 2.76 2.75 2.73 2.70 2.55 2.3612740 SB 4 68.5 2.27 50.00 3.65 3.68 3.68 3.66 3.56 3.4013180 SB 4 73.9 4.89 50.00 2.66 2.65 2.63 2.59 2.44 2.2513460 NB 4 46.8 1.75 50.00 3.44 3.46 3.46 3.44 3.33 3.1613720 NB 4 55.9 4.03 50.00 2.55 2.54 2.51 2.47 2.31 2.1213760 EB 4 55 3.23 50.00 2.80 2.80 2.78 2.75 2.60 2.4113760 NB 4 42.9 3.81 50.00 2.30 2.28 2.25 2.21 2.03 1.8313940 NB 4 31.1 2.69 50.00 2.32 2.31 2.27 2.23 2.06 1.8514200 NB 4 52.3 2.08 50.00 3.35 3.37 3.36 3.34 3.22 3.0514500 EB 4 28.3 1.75 50.00 2.72 2.71 2.69 2.65 2.50 2.3114520 EB 4 34.4 2.76 50.00 2.41 2.40 2.37 2.32 2.16 1.9614540 EB 4 39.7 2.48 50.00 2.71 2.71 2.68 2.65 2.50 2.3114540 NB 4 40.6 2.90 50.00 2.55 2.54 2.51 2.47 2.31 2.1214560 EB 4 33.7 3.68 50.00 2.08 2.05 2.02 1.97 1.78 1.5714960 NB 4 71.8 5.62 50.00 2.46 2.45 2.42 2.38 2.21 2.0115040 NB 4 50.6 2.89 50.00 2.84 2.84 2.82 2.78 2.64 2.45


Max Flow Depth (mm)



8070 SB 4 39.1 4.43 50.00 2.05 2.02 1.98 1.93 1.75 1.538080 WB 4 65.7 3.41 50.00 2.97 2.98 2.96 2.93 2.79 2.618080 EB 4 76.5 3.90 50.00 3.00 3.01 2.99 2.96 2.82 2.648100 EB 4 53.2 3.88 50.00 2.53 2.52 2.50 2.46 2.30 2.108100 WB 4 54.5 3.99 50.00 2.53 2.52 2.49 2.45 2.29 2.099000 NB 4 44.5 1.17 50.00 4.03 4.07 4.08 4.08 3.99 3.859250 WB 4 25 1.56 50.00 2.70 2.70 2.68 2.64 2.49 2.309270 EB 4 90 3.16 50.00 3.57 3.59 3.59 3.58 3.47 3.319290 EB 4 95.5 3.07 50.00 3.72 3.75 3.75 3.74 3.63 3.489420 NB 4 58.8 1.57 50.00 4.02 4.06 4.07 4.06 3.97 3.8310000 SB 4 40.8 3.03 50.00 2.50 2.49 2.46 2.43 2.26 2.0610360 NB 4 71.2 3.30 50.00 3.14 3.15 3.14 3.11 2.98 2.8010360 EB 4 65.9 4.95 50.00 2.50 2.49 2.46 2.42 2.26 2.0610390 EB 4 59.6 4.99 50.00 2.38 2.36 2.33 2.29 2.12 1.9210400 NB 4 79.1 3.61 50.00 3.16 3.17 3.16 3.14 3.01 2.8310500 NB 4 99.7 3.41 50.00 3.62 3.64 3.64 3.63 3.52 3.3610800 SB 4 36.9 2.70 50.00 2.52 2.51 2.48 2.44 2.28 2.0811000 NB 4 47.4 4.79 50.00 2.17 2.14 2.11 2.06 1.88 1.6711340 SB 4 19.8 1.01 50.00 2.95 2.96 2.94 2.91 2.77 2.5911400 SB 4 47.3 1.63 50.00 3.57 3.60 3.60 3.58 3.47 3.3111500 WB 4 117.3 4.20 50.00 3.55 3.57 3.57 3.55 3.44 3.2811510 NB 4 121.2 4.20 50.00 3.60 3.63 3.63 3.61 3.50 3.3411860 SB 4 78.1 2.80 50.00 3.53 3.55 3.55 3.53 3.42 3.2612000 NB 4 36.9 2.46 50.00 2.63 2.62 2.60 2.56 2.41 2.2112340 NB 4 31 4.22 50.00 1.87 1.84 1.79 1.74 1.54 1.3212360 SB 4 59.7 5.44 50.00 2.28 2.26 2.23 2.19 2.01 1.8112350 NB 4 28.8 4.92 50.00 1.67 1.63 1.58 1.52 1.32 1.0912680 SB 4 48.8 2.92 50.00 2.77 2.77 2.75 2.72 2.57 2.3812680 NB 4 49.5 2.06 50.00 3.28 3.29 3.29 3.26 3.14 2.9712700 NB 4 27.5 1.25 50.00 3.13 3.14 3.13 3.10 2.97 2.7912700 SB 4 36.7 2.20 50.00 2.76 2.76 2.74 2.70 2.55 2.3712700 EB 4 13 0.80 50.00 2.70 2.70 2.68 2.64 2.49 2.3012720 NB 4 48.2 2.52 50.00 2.95 2.96 2.94 2.91 2.77 2.5912740 EB 4 38.7 3.79 50.00 2.19 2.17 2.14 2.09 1.91 1.7012740 SB 4 56.5 3.61 50.00 2.69 2.69 2.67 2.63 2.48 2.2912780 SB 4 68.7 2.31 50.00 3.63 3.65 3.66 3.64 3.53 3.3813200 SB 4 78.7 2.79 50.00 3.55 3.57 3.57 3.56 3.44 3.2813460 NB 4 60.4 1.71 50.00 3.91 3.95 3.96 3.95 3.86 3.7113740 EB 4 58 3.02 50.00 2.96 2.97 2.95 2.92 2.78 2.6013760 NB 4 54.4 4.07 50.00 2.50 2.49 2.46 2.42 2.26 2.0613760 EB 4 36.7 3.60 50.00 2.19 2.17 2.13 2.09 1.91 1.7013780 NB 4 50.4 3.82 50.00 2.48 2.47 2.45 2.40 2.24 2.0413800 NB 4 49.9 3.77 50.00 2.49 2.48 2.45 2.41 2.24 2.0513930 NB 4 34.4 2.81 50.00 2.39 2.37 2.34 2.30 2.13 1.9313920 WB 4 18.9 4.51 50.00 1.40 1.36 1.30 1.24 1.02 0.7813930 WB 4 9.5 5.56 50.00 0.86 0.80 0.73 0.65 0.41 0.1514140 NB 4 63.3 1.86 50.00 3.86 3.89 3.90 3.89 3.79 3.6414520 EB 4 38.5 2.71 50.00 2.56 2.56 2.53 2.49 2.33 2.1314540 EB 4 39.6 2.32 50.00 2.79 2.79 2.77 2.74 2.59 2.4014540 NB 4 39.1 2.99 50.00 2.47 2.46 2.43 2.39 2.22 2.0214550 NB 4 40.1 2.97 50.00 2.50 2.49 2.46 2.43 2.26 2.0614560 EB 4 17.6 3.53 50.00 1.53 1.49 1.44 1.37 1.16 0.9314550 EB 4 32.6 3.65 50.00 2.05 2.03 1.99 1.94 1.75 1.54


Max Flow Depth (mm)



Appendix H Soil test results

Scone Research Centre, PO Box 283 Scone 2337, 709 Gundy Road Scone 2337 Ph: 02 6545 1666, Fax: 02 6545 2520

SOIL TEST REPORT Page 1 of 2

Scone Research Centre REPORT NO: SCO11/346R1 REPORT TO: J Tidswell Network Geotechnics Pty Ltd Unit 12, 9-15 Gundah Road Mt Kuring-Gai NSW 2080 REPORT ON: Three soil samples NB11363 PRELIMINARY RESULTS ISSUED: Not issued REPORT STATUS: Final DATE REPORTED: 21 October 2011 METHODS: Information on test procedures can be obtained from Scone Research Centre TESTING CARRIED OUT ON SAMPLE AS RECEIVED THIS DOCUMENT MAY NOT BE REPRODUCED EXCEPT IN FULL

SR Young (Laboratory Manager)

SOIL

CO

NSE

RV

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(%)

C6A

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P8A

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silt

f san

d c

sand

G

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%

1 G

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4 T

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0.5m

17

12

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12

0.

57

67

2 G

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0.5m

41

15

37

6

1 0.

66

48

3 G

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0.9

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21

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65

64

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Experienced people protecting your resources

709 Gundy Road, Scone NSW 2337

PO Box 283, Scone NSW 2337 P: 02 6545 1666 F: 02 6545 2520 M: 0408 446 132

J Tidswell Network Geotechnics Pty Ltd Unit 12, 9-15 Gundah Road Mt Kuring-Gai NSW 2080

21 October 2011 SCO11/346 Dear J Tidswell

Analysis of three soil samples – soil erodibility factor

The Soil Conservation Service has analysed three soil samples (Soil test report SCO11/346R1) for particle size analysis-mechanical dispersion (clay, silt, fine sand, coarse sand and gravel) and organic carbon (OC) to determine the soil erodibility (K) factor (Rosewell 1993). The surface soil structure was assumed to be medium granular and the profile permeability was assumed to be slow to moderate.

Lab No Sample Id K factor Rating

1 G14224 TP38 0.5m 0.028 Moderate

2 G14174 TP75 0.5m 0.029 Moderate

3 G14226 TP104 0.9m 0.049 High

This interpretation was based on the soil samples being representative, and literature guidelines. If you have any queries, please contact me on (02) 6545 1666. Yours faithfully

SR Young References

Rosewell CJ (1993) Soiloss – A program to assist in the selection of management practices to reduce erosion. Department of Conservation and Land Management.


709 Gundy Road, Scone NSW 2337 PO Box 283, Scone NSW 2337

P: 02 6545 1666 F: 02 6545 2520 M: 0408 446 132

Josh Tidswell

Network Geotechnics

Unit 12

9-15 Gundah Road

Mt Kuring-gai NSW 2080

7 November 2011 SCO11/368

Dear Josh Tidswell

Analysis of two soil samples – NB11363

The Soil Conservation Service has analysed two soil samples (Soil test report

SCO11/368R1) for particle size analysis-mechanical dispersion (clay, silt, fine sand, coarse

sand and gravel) and organic carbon (OC) to determine the soil erodibility (K) factor

(Rosewell 1993). The surface soil structure was assumed to be medium granular and the

profile permeability was assumed to be slow to moderate.


1 G14212 0.030 Moderate

2 G14227 0.053 High

This interpretation was based on the soil samples being representative, and literature

guidelines. If you have any queries, please contact me on (02) 6545 1666.

Yours faithfully

SR Young

References

Rosewell CJ (1993) Soiloss – A program to assist in the selection of management practices

to reduce erosion. Department of Conservation and Land Management.

Scone Research Centre, PO Box 283 Scone 2337, 709 Gundy Road Scone 2337

Ph: 02 6545 1666, Fax: 02 6545 2520

SOIL TEST REPORT

Page 1 of 2

Scone Research Centre

REPORT NO: SCO11/368R1

REPORT TO: Josh Tidswell

Network Geotechnics Pty Ltd

Unit 12

9-15 Gundah Road


REPORT ON: Two soil samples

Job No: NB11363

PRELIMINARY RESULTS

ISSUED: Not issued

REPORT STATUS: Final

DATE REPORTED: 7 November 2011

METHODS: Information on test procedures can be obtained from Scone

Research Centre

TESTING CARRIED OUT ON SAMPLE AS RECEIVED

THIS DOCUMENT MAY NOT BE REPRODUCED EXCEPT IN FULL

SR Young

(Laboratory Manager)

SOIL CONSERVATION SERVICE

Scone Research Service Centre

Page 2 of 2

Report No: SCO11/368R1

Client Reference: Josh Tidswell

Network Geotechnics

Unit 12

9-15 Gundah Road


Lab No Method P7C/2 Particle Size Analysis – mech dis (%) P8A/2 C6A/2

Sample Id clay silt f sand c sand gravel D% OC (%)

1 G14212 44 34 11 11 0 47 0.21

2 G14227 28 49 17 3 3 61 0.22

END OF TEST REPORT


709 Gundy Road, Scone NSW 2337

PO Box 283, Scone NSW 2337 P: 02 6545 1666 F: 02 6545 2520 M: 0408 446 132

Jacob Lloyd SGS Australia Pty Ltd 15 / 33 Maddox St Alexandria NSW 2015

28 October 2011 SCO11/345 Dear Jacob Lloyd

Analysis of one soil sample – PO: 211335

The Soil Conservation Service has analysed one soil sample (TP25 0.5m) for particle size analysis-mechanical dispersion (clay, silt, fine sand, coarse sand and gravel) and organic carbon (OC) to determine the soil erodibility factor (K factor) (as described by Rosewell 1993). The surface soil structure was assumed to be medium granular and the profile permeability was assumed to be slow to moderate.


1 TP25 0.5m 0.030 Moderate

This interpretation was based on the soil sample being representative, and literature guidelines. If you have any queries, please contact me on (02) 6545 1666. Yours faithfully

SR Young References

Rosewell CJ (1993) Soiloss – A program to assist in the selection of management practices to reduce erosion. Department of Conservation and Land Management.

Scone Research Centre, PO Box 283 Scone 2337, 709 Gundy Road Scone 2337 Ph: 02 6545 1666, Fax: 02 6545 2520

SOIL TEST REPORT Page 1 of 2

Scone Research Centre REPORT NO: SCO11/345R1 REPORT TO: Jacob Lloyd SGS Australia Pty Ltd 15 / 33 Maddox St Alexandria NSW 2015 REPORT ON: One soil sample PO: 211335 PRELIMINARY RESULTS ISSUED: Not issued REPORT STATUS: Final DATE REPORTED: 28 October 2011 METHODS: Information on test procedures can be obtained from Scone Research Centre TESTING CARRIED OUT ON SAMPLE AS RECEIVED THIS DOCUMENT MAY NOT BE REPRODUCED EXCEPT IN FULL

SR Young (Laboratory Manager)

SOIL

CO

NSE

RV

AT

ION

SE

RV

ICE

Sc

one

Res

earc

h Se

rvic

e C

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Sa

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ay

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f san

d c

sand

gr

avel

O

C (%

)

1 TP

25 0

.5m

37

29

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5

11

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EN

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TEST CERTIFICATE

CLIENT:

PROJECT:

LABNO.

69484

Sampled By:

Job Number:

Date Tested:

Comments:

Approved Signatory: Date:

Northern Road Upgrade

Sinclair Knight MerzPO Box 164 St Leonards NSW 1590

PERCENT DISPERSION OF A SOIL

Dispersing AgentDispersing AgentSOURCE SAMPLE DESCRIPTION (%)DISPERSION

PERCENT% Passing

without0.005mm

% Passing 0.005mm

with

57TP 103

SAMPLE

92621.30m

SILTY CLAY:brown, medium plasticity, trace

of fine to coarse sand, trace of fine gravel.

NOTES TO TESTINGTest Procedure: AS1289 3.8.2 Determination of the percent dispersion of a soil

Client

Chris Lloyd

116-133

3.11.11

03.11.11

This document is issued in accordance with NATA’s accreditation requirements

Accreditation No. 1452

SGS Australia Pty LtdUnit 15, 33 Maddox Street (PO Box 6432)Alexandria NSW 2015Australia

This document is issued by the Company subject to its General Conditions of Service (www.sgs.com/terms_and_conditions.htm). Attention is drawn to the limitations of liability, indemnification and jurisdictional issues established therein.

This document is to be treated as an original within the meaning of UCP 600. Any holder of this document is advised that information contained hereon reflects the Company's findings at the time of its intervention only and within the limits of client's

instructions, if any. The company's sole responsibility it to its client and this document does not exonerate parties to a transaction from exercising all their rights and obligations under the transaction documents. Any unauthorized alteration, forgery or

falsification of the content or appearance of this document is unlawful and offenders may be prosecuted to the fullest extent of the law.

ABN 44 000 964 278ph: +61 (0)2 8594 0481fax: +61 (0)2 8594 0499

PF-(AU)-[IND(MTE)]-(GEN)-RPT-619.VER1.09.02.2011 – Page 1 of 1

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