Waitaha Hydro Scheme Terrestrial Flora Description and Assessment … 15 - WHS... · Waitaha Hydro Scheme Terrestrial Flora Description and Assessment of Effects Prepared By: TACCRA

Waitaha Hydro Scheme

Terrestrial Flora Description

and

Assessment of Effects

Prepared By: TACCRA Ltd.

Date: 31 December 2013

1

Disclaimer

This paper has been prepared at the request of and for the purposes of the client (Westpower

Ltd.) only. Neither TACCRA Ltd. nor any of its shareholders/employees accept any

responsibility on any grounds whatsoever, including liability in negligence or for the manner

in which information contained herein is subsequently used, to any other person or party.

D. J. Derks

For:

TACCRA Ltd.

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Table of Contents

Executive Summary ........................................................................................................................ 5

1.0 Introduction ............................................................................................................................. 13 2.0 Location of Works ................................................................................................................... 15

2.1 Headworks and Associated Works/Structures = Area 1 ..................................................... 15 2.2 Access Road, Powerhouse and Associated Works/Structures = Area 2 ............................. 15

3.0 Vegetation Description and Assessment Method – Area 1 ..................................................... 16

3.1 Vegetation Type Descriptions for Area 1 ........................................................................... 16 4.0 Vegetation Effects In Area 1 ................................................................................................... 26

4.1 Weir ..................................................................................................................................... 28 4.2 Intake Channel ..................................................................................................................... 28 4.3 Intake Structure and Intake Portal ....................................................................................... 29

4.4 Tunnel Portal Entrance ........................................................................................................ 30 4.5 Intake Access Road from Tunnel Portal Entrance to Intake Structures .............................. 30

4.6 Road to Contractors’ Facilities Area ................................................................................... 31

4.7 Contractors’ Facilities Area ................................................................................................ 32 4.8 Flushing Tunnel Outlet ........................................................................................................ 33

5.0 Other Observations Relating to Vegetation – Area 1 .............................................................. 33 6.0 Vegetation Description and Assessment Method - Area 2 ..................................................... 34

6.1 Vegetation Type Descriptions for Area 2 ........................................................................... 34 7.0 Vegetation Effects in Area 2 ................................................................................................... 48

7.1 Tunnel Portal Exit and Construction Apron ........................................................................ 49 7.2 Access Road and Transmission Line .................................................................................. 50 7.3 Waterway Training and Flood Protection – Alpha Creek ................................................... 52

7.4 Powerhouse and Switchyard ............................................................................................... 53 7.5 Powerhouse to Tunnel Portal Exit Access Road and Penstock ........................................... 54

7.6 Tailrace ................................................................................................................................ 54

7.7 Stopbank Protection for Powerhouse, Switchyard, Tailrace, Penstock and Access Road .. 55

8.0 Other Observations Relating to Vegetation – Area 2 .............................................................. 56 9.0 Significance and Natural Values Assessment ......................................................................... 57

9.1 Area 1 and Area 2 Vegetation Type(s) – Significance and Natural Heritage Value

Assessment ................................................................................................................................ 63

9.2 Summary of Vegetation Significance and Natural Heritage Value .................................... 72 10.0 Recommended Monitoring, Mitigation and Remediation ..................................................... 75

10.1 Area 1 - Monitoring/Mitigation/Remediation: .................................................................. 75

10.2 Area 2 - Monitoring/Mitigation/Remediation: .................................................................. 76 11.0 Summary/Conclusions .......................................................................................................... 77

11.1 Area 1 - Headworks and Associated Structures ................................................................ 77 11.2 Area 2 - Tunnel Portal Exit, Access Road/Transmission Line, Stream Training,

Powerhouse, Switchyard, Penstock, Tailrace and Stopbank Facilities ..................................... 80 Acknowledgements ....................................................................................................................... 83

References ..................................................................................................................................... 83 List of Appendices ........................................................................................................................ 84

Appendix A Map 1: Project Area General Location. ................................................................ 85

Appendix A Diagram 1: Headworks Infrastructure Concept. ................................................... 87 Appendix A Map 2: Infrastructure Locations and Vegetation Type Delineations – Area 1. .... 89 Appendix A Map 3: Infrastructure Locations and Vegetation Type Delineations – Area 2. .... 91 Appendix A Map 4: Wilberg Ecological District and Waitaha Catchment With LCDB Land

Cover Types. ............................................................................................................................. 93

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Appendix A Map 5: Base Area Delineation on Topographic Mapping. ................................... 95

Appendix A Map 6: Base Area LCDB Land Cover Types. ...................................................... 97 Appendix B: Species List with Maori and Common Names .................................................... 99

List of Figures

Figure 1 - Example of Vegetation Types 1/1 & 1/3: ..................................................................... 17

Figure 2 - Example of Vegetation Types 1/1 & 1/2: ..................................................................... 18 Figure 3 - Example of Vegetation Types 1/1 & 1/3: ..................................................................... 20 Figure 4 - Example of Vegetation Types 1/1 & 1/3: ..................................................................... 21 Figure 5 - Example of Vegetation Type 1/3: ................................................................................. 21 Figure 6 - Example of Vegetation Type 1/3: ................................................................................. 22

Figure 7 - Example of Vegetation Types 1/1 & 1/3: ..................................................................... 22

Figure 8 - Example of Vegetation Type 1/3 Shrub Component Cover in Morgan Gorge: ........... 23 Figure 9 - Example of Vegetation Type 1/3: ................................................................................. 23

Figure 10 - Example of Vegetation Type 1/4: ............................................................................... 25 Figure 11 - Example of Vegetation Type 1/4: ............................................................................... 25 Figure 12 - Example of Vegetation Type 2/1: ............................................................................... 36

Figure 13 - Example of Vegetation Type 2/2: ............................................................................... 37 Figure 14 - Example of Vegetation Type 2/2: ............................................................................... 38 Figure 15 - Example of Vegetation Types 2/3 & 2/3A: ................................................................ 39

Figure 16 - Example of Vegetation Type 2/3B: ............................................................................ 40 Figure 17 - Example of Vegetation Type 2/4: ............................................................................... 41

Figure 18 - Example of Vegetation Types 2/5 & 2/6: ................................................................... 43 Figure 19 - Example of Vegetation Types 2/5 & 2/6: ................................................................... 44 Figure 20 - Example of Vegetation Type 2/6: ............................................................................... 45

Figure 21 - Example of Vegetation Type 2/7: ............................................................................... 46

Figure 22 - Example of Vegetation Type 2/8: ............................................................................... 47 Figure 23 - Example of Vegetation Type 2/9: ............................................................................... 48

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List of Tables

Table 1: Weir Construction Distances and Potentially Affected Areas Within Vegetation Type.28 Table 2: Intake Channel Potentially Affected Areas Within Vegetation Type. ............................ 29 Table 3: Intake Structure and Intake Portal Potentially Affected Areas Within Vegetation Types.

....................................................................................................................................................... 30

Table 4: Tunnel Portal Entrance Potentially Affected Areas Within Vegetation Types. ............. 30 Table 5: Tunnel Portal Entrance Apron, Intake Access Road and River Protection Potentially

Affected Areas Within Vegetation Types. .................................................................................... 31 Table 6: Road to Contractors’ Facilities Distances and Potentially Affected Areas Within

Vegetation Types. .......................................................................................................................... 32

Table 7: Contractors’ Facilities Potentially Affected Area Within Vegetation Type. .................. 32 Table 8: Flushing Tunnel Outlet Potentially Affected Areas Within Vegetation Types. ............. 33 Table 9: Tunnel Portal Exit and Construction Apron Potentially Affected Area Within

Vegetation Types. .......................................................................................................................... 49

Table 10: Access Road Distances and Potentially Affected Areas Within Vegetation Types. .... 51 Table 11: Waterway Training and Flood Protection Works (Alpha Creek) Distance and

Potentially Affected Area Within Vegetation Type. ..................................................................... 53

Table 12: Powerhouse, Switchyard and Hard-fill Zone Potentially Affected Area Within

Vegetation Type. ........................................................................................................................... 53

Table 13: Powerhouse to Tunnel Portal Exit Road and Penstock Distance and Potentially

Affected Areas Within Vegetation Type. ...................................................................................... 54

Table 14: Tailrace Distance and Potentially Affected Area Within Vegetation Type. ................. 55 Table 15: Stopbank Distance and Potentially Affected Area Within Vegetation Type. ............... 56 Table 16: Criteria Framework for Determining Significance and Natural Heritage Values for

Purposes of Section 6(c) of the Resource Management Act 1991 (RPS & WDP) and Natural

Heritage Values (CMS). ................................................................................................................ 58

Table 17: LCDB Land Cover Class and Analogous Vegetation Type Area Summaries and

Comparisons for Wilberg Ecological District, Waitaha Catchment and Base Area and the

Scheme’s Project Footprint. .......................................................................................................... 62 Table 18: Summary of Significant Indigenous Vegetation and High Natural Heritage Value

Assessment Criteria Applicable To Area 1 and Area 2 Vegetation. ............................................. 73

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Executive Summary

1. Potential Environmental Effects:

Westpower is proposing a run-of-river hydroelectric power scheme development in the Waitaha

River valley, the Waitaha Hydro Scheme (the Scheme). The land on which the predominant

amount of indigenous vegetation potentially affected by the Scheme occurs is part of the

Waitaha Forest conservation unit being Stewardship Land administered by the Department of

Conservation (DOC). Various types of indigenous vegetation cover are present across the entire

area. No significant historical anthropogenic modification has occurred at any site potentially

affected by the Scheme within the Waitaha Forest conservation unit.

The Scheme consists of two sets of components in two distinct areas (see Appendix A, Map 1)

that will affect vegetation in various ways. (N.B: the order of description here is not necessarily

the order of any construction activity):

Area 1: Headworks including construction and maintenance of:

a) Weir.

b) Water intake structures.

c) A tunnel portal entrance and short section of access road at the true-right upstream end of

Morgan Gorge, just below Kiwi Flat.

d) A short access road to a contractors’ facilities area and the area itself on a small alluvial

terrace on the true-right c. 250 metres upstream of Morgan Gorge entrance.

e) A flushing tunnel outlet in the Morgan Gorge.

A main tunnel will provide access from the lower Waitaha Valley to the various

headworks facilities. It will contain flushing basin structures and a penstock. Construction

and operation of these underground components will not affect vegetation.

Area 2: Powerhouse and access road works including construction and maintenance of:

a) A heavy transport access road with power transmission line parallel, from the true left

side of Macgregor Creek in the lower valley to the site of powerhouse construction, with

roading extending on from the powerhouse to the tunnel portal exit site. N.B: Vegetation

description and effects assessment given in this report only pertain to that part of the

access road and transmission line shown on Appendix A, Map 3. The rest of the access

road and transmission line are expected to pass over private farmland and possibly other

Crown land and legal road. Vegetation effects, if any, on these areas will depend on

location of infrastructure. This is not finalised by Westpower at the time of preparation of

this report.

b) A section of access road from the powerhouse to the tunnel portal exit.

c) A tunnel portal exit on the true-right of the Waitaha River, c. 1.5 km in straight line

distance below the nearest part of the area of headworks infrastructure (and tunneling

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excavation itself, while not affecting vegetation, will require some area e.g. for access,

equipment and spoil handling/transfer).

d) Powerhouse and switchyard.

e) Penstock to convey water from the tunnel portal exit to the powerhouse.

f) Tailrace to carry water from the powerhouse back to the river.

g) Stopbank river protection for powerhouse, switchyard, a portion of access road and

penstock facilities.

h) Waterway training and flood protection at Alpha Creek (to protect the access road and

tailrace).

Two streams that are shown on the NZTopo50 1:50,000 map of the area but are unnamed have

been assigned in-house names by Westpower for descriptive purposes. These are:

1. Granite Creek = the first unnamed stream shown on map sheet NZTopo50-BW17 south

of Macgregor Creek.

2. Alpha Creek = the second stream shown on map sheet NZTopo50-BW17 south of

Macgregor Creek.

Vegetation clearance or disturbance during construction activities within the Scheme’s project

footprint (the area affected by construction), and the permanent removal of vegetation in the

lesser area of the Scheme’s operational footprint (areas permanently occupied by Scheme

components), are the principal environmental effect on indigenous vegetation.

The following table provides a summary of the areas of vegetation potentially affected by the

Scheme. It is important to note that areas given as construction, permanent and riparian

(construction) are not additive. The construction area is the expected maximum area potentially

affected by each Scheme component and the construction total is an indication of the Scheme’s

project footprint as it pertains to vegetation effect. Areas given as permanent and riparian areas

are sub-areas for purposes of describing amount of vegetation clearance associated with a given

Scheme component. In the case of permanent areas these indicate the operational footprint of

each Scheme component and for the Scheme in total. Riparian areas are given because activities

affecting indigenous vegetation in riparian margins will require consideration for regional and

district planning provision purposes.

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Areas of Vegetation Potentially Affected by Scheme Components and in Total:

Scheme Component(s) Construction

(ha)

Permanent

(ha)

Riparian

(Construction,

ha)

Area 1: Headworks and Associated

Infrastructure Item(s)

Weir. 0.0050 0.0010 0.0

Intake Channel. 0.0325 0.0163 0.0

Intake Structure and Intake Portal. 0.0478 0.0278 0.0294

Tunnel Portal Entrance. 0.0187 0.0187 0.0

Tunnel Portal Entrance Apron, Intake Access

Road and River Protection at Road Toe.

0.1370 0.0790 0.0410

Road to Contractors’ Facilities Area. 0.1040 0.0 0.0300

Contractors’ Facilities Area. 0.2200 0.0 0.0

Flushing Tunnel Outlet. 0.0100 0.0100 0.0100

Area 1 Sub-totals 0.5750 0.1528 0.1104

Area 1 Sub-totals Rounded Up 0.58 0.16 0.12

Area 2: Infrastructure Item(s)

Tunnel Portal Exit and Construction Apron. 0.2480 0.1800 0.0

Access Road and Transmission Line Parallel. 2.5470 2.4198 0.0450

Waterway Training and Flood Protection at

Alpha Creek.

0.3375 0.1688 0.1750

Powerhouse, Switchyard and Hard-fill Area. 0.3150 0.3150 0.0

Powerhouse to Tunnel Portal Exit Access Road

and Penstock.

0.1275 0.1275 0.0

Tailrace. 0.2000 0.2000 0.0250*

Stopbank as River Protection for Powerhouse,

Switchyard, Tailrace, Penstock and Access

Road.

0.1755 0.1169 0.1755

Area 2 Sub-totals 3.9505 3.5280 0.4205

Area 2 Sub-totals Rounded Up 3.96 3.53 0.43

Scheme Totals 4.5255 3.6808 0.5309

Scheme Totals Rounded Up 4.53 3.69 0.54 Note: Areas given as rounded sub-totals and totals in the above table are rounded up to two decimal places in every

case so as to avoid dropping any area as could occur if using conventional rounding of figures less than five.

Note: Areas do not include non-vegetated zones affected by work components or parts thereof, e.g. where these are

on exposed bedrock or in active river bed and are unvegetated pre-project. All are indicative based on

November 2013 Scheme plans supplied by Westpower and may vary from those given above depending on final

design, survey and siting.

Note: Riparian areas are for streams >3metres wide where provisions of the Proposed Regional Land and Water

Plan (WCRC, 2013) and the Westland District Plan (WDC, 2002) prescribe 10 metre riparian margin widths.

Streams 1 – 3 meters wide occur in or near various areas of activity and provisions of the Proposed Regional Land

and Water Plan (WCRC, 2013) prescribe 10 metre wide riparian margins for these if slope is >12o and 5 metre

wide riparian margins otherwise. This requirement will add some (expected to be relatively minor) area to the

estimates given above, however the detailed field survey and mapping of small stream location was not a component

of work undertaken as the basis of this report. The number and exact location of streams 1 - 3 metres wide that are

potentially affected will need to be determined for regional planning provision purposes, although it is not

considered that potential effects on vegetation will be any greater than already assessed and considered.

Note: Tailrace riparian area potentially affected as marked * is an estimate based on an oblique angle crossing of

the Waitaha River true-right 10 metre riparian zone by the 20 metre wide tailrace – actual affected area may vary

depending on final angle of traverse of the tailrace through the riparian margin, however any variation in affected

area carrying vegetation is expected to be minimal.

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2. Assessments Undertaken:

Fieldwork was undertaken in the periods 22/8/12 – 23/8/12 and 12/9/12 – 13/9/12 with a

subsequent visit on 30/9/13. It covered land administered by DOC within and surrounding the

Scheme project footprint. Areas covered are shown in Appendix A, Maps 1, 2 and 3. It involved

walkthrough as terrain permitted, but where possible by transect across the run of land. Use of

any predefined sampling system (random or systematic) on all areas was deemed impractical due

primarily to difficulty of terrain particularly about the headworks sites. Representative areas

were covered based on interpretation of cover type from aerial photography and field

observation.

This report:

Describes the main vegetation types present, and those potentially affected by the

Scheme.

Assesses uniqueness of the potentially affected vegetation types and whether any areas

have high natural heritage value in terms of the West Coast Conservation Management

Strategy 2010 – 2020 (DOC 2010).

Provides an assessment of significance of indigenous vegetation against criteria and

guidelines in the West Coast Regional Policy Statement (WCRC, 2000) and the Westland

District Plan (WDC, 2002).

Describes the potential effects, including residual effects, of the Scheme on indigenous

terrestrial vegetation.

Recommends monitoring and mitigation/site rehabilitation.

3. Results of Assessments:

Vegetation within Area 1, Area 2 and their surrounds would be considered as having high natural

heritage values under the West Coast Conservation Management Strategy 2010 – 2020 (DOC,

2010) criteria of intactness and viability. It is considered significant indigenous vegetation under

provisions of the Westland District Plan (WDC, 2002) on the basis of two criteria - intactness

and size of area, and protected status.

The predominant vegetation types present in Area 1 are typical of streamside and side-slope

areas across a relatively wide altitudinal range (e.g. 100 – 500 m.a.s.l.) within forested Westland

catchments. The vegetation types present on the recent alluvial flat and terrace sequence in

Area 2 are also typical of forested Westland catchments. GIS analysis undertaken using the Land

Cover Database (LCDB) land cover classes matched to the indigenous forest type assemblages

(all Vegetation Types except Vegetation Type 1/4, a shrubland type in Area 1) potentially

affected by the Scheme shows these are present across 27,903 hectares of the Wilberg Ecological

District. This is 44% of its total indigenous vegetation cover. They are present across

4,334 hectares of the Waitaha Catchment. This is 36% of its total indigenous vegetation cover.

The vegetation type assemblages present are common and widely represented in both the

Wilberg Ecological District and the Waitaha catchment. The indigenous forest assemblages also

occur extensively in catchments of similar valleys throughout central Westland. Vegetation

9

Type 1/4, a small area of which is within the Scheme project footprint is analogous to the LCDB

Sub Alpine Shrubland land cover class. GIS analysis shows it occurs over 17,269 hectares in the

Wilberg Ecological District and therefore comprises 27% of its total indigenous vegetation

cover. It is present across 4,249 hectares of the Waitaha catchment and therefore comprises 35%

of its total indigenous vegetation cover. Like the indigenous forest vegetation of Area 1 and

Area 2, this shrubland vegetation is also common and widely represented, not only in the areas

noted above but in other valleys throughout central Westland.

No threatened plant species and no vegetation community uniqueness, attributes or species

associations/presence were identified within or surrounding the Scheme’s project footprint.

For streams >3 metres wide, provisions of the Proposed Regional Land and Water Plan (WCRC,

2013) and the Westland District Plan (WDC, 2002) prescribe 10 metre riparian margin widths.

Vegetation types present in riparian margins in Area 1 and Area 2 are not unique or

distinguished floristically from their counterparts not occupying a riparian strip. It is the arbitrary

riparian designation of fixed-width distance from stream bank, not vegetation, that distinguishes

these zones and that may have environmental planning restrictions that would not otherwise

apply.

For streams 1 – 3 metres wide, provisions of the Proposed Regional Land and Water Plan

(WCRC, 2013) prescribe 10 metre wide riparian margins if dominant slope angle is >12o and

5 metre riparian margins otherwise. This requirement will add some (expected to be relatively

minor) area to available estimates of affected riparian area, however the detailed field survey and

mapping of small stream location was not a component of work undertaken as the basis of this

report. The number and exact location of streams 1 - 3 metres wide that are potentially affected

will need to be determined for regional planning provision purposes, although it is not

considered that potential effects on vegetation will be any greater than already assessed and

considered.

The scale of proposed works within Area 1 is well within the spatial scale of natural disturbances

typical of this environment i.e., does not represent clearance of large areas in conjunction with a

change in land use and cover type. The nature of vegetation disturbance (removal) caused by the

proposed work would not be deemed inconsistent with natural disturbance events e.g. slips, at

this or similar sites. Construction involves clearance or at least some disturbance to

approximately 0.58 hectares of indigenous vegetation. This area, based on LCDB land cover

classes, is an extremely low proportion of the types present being:

0.15% of the c. 396 hectares of the similar indigenous forest vegetation

(385 hectares)/sub alpine shrubland (11 hectares) assemblages contained in the Base

Area, a zone below the 400 metre contour and on the true-right of the Waitaha River/true

left of Macgregor Creek carrying vegetation typical of that in the Scheme’s project

footprint, containing and surrounding the project footprint and considered its general

locale.

0.007% of the 8,583 hectares of their counterparts in the Waitaha catchment.

0.001% of the 45,172 hectares of their counterparts in the Wilberg Ecological District.

The headworks operational footprint is significantly less again, being 27% of the project

footprint for headworks. Following the construction phase, the activity becomes relatively

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benign, and appears to have low likelihood of requiring disturbance of vegetation at any of the

areas. Therefore, the proposed activity is not considered to have any long-term detrimental effect

on vegetation surrounding the various sites. Natural regeneration should occur across any areas

affected by construction (except those areas occupied by structural components).

Scheme effects on indigenous vegetation in Area 1 are considered negligible.

For the Scheme components in Area 2, scale of proposed works is well within the spatial scale of

natural features contributing to discontinuity in vegetation cover e.g:

a. The narrow linear footprint of the access road/transmission corridor, at 20 metres

maximum, is less than half the width of the Waitaha River bed at its narrowest in the

portion that the road parallels. (Note: for purposes of estimating vegetation clearance for

the road/transmission line an average of 15 metres has been used).

b. The alluvial flat area on which the proposed powerhouse, switchyard, access road to the

tunnel portal exit, tailrace and stopbank are located is of similar width to the Waitaha

River bed adjacent to it (and it is already predominantly open i.e. not carrying closed-

canopy vegetation cover).

Construction involves clearance or at least some disturbance to 3.96 hectares of indigenous

vegetation that, based on LCDB land cover classes, is an extremely low proportion of the types

present being:

1.0% of the c. 385 hectares of the similar indigenous forest vegetation assemblages

contained in the Base Area, a zone below the 400 metre contour and on the true-right of

the Waitaha River/true left of Macgregor Creek carrying vegetation typical of that in the

Scheme project footprint, containing and extending beyond the project footprint and

considered its general locale.

0.09% of the 4,334 hectares of their counterparts in the Waitaha catchment.

0.01% of the 27,903 hectares of their counterparts in the Wilberg Ecological District.

The same pertains for all Scheme components in Area 2 as for Area 1, where, following the

construction phase, the activity becomes relatively benign, and appears to have low likelihood of

requiring disturbance of vegetation. Therefore, the proposed activity is not considered to have

any long-term detrimental effect on vegetation surrounding the various sites. Natural

regeneration should occur across any areas affected by construction (except those areas occupied

by structural components).

Forming and maintaining an access road to the powerhouse and tunnel portal exit affects the

greatest area and range of vegetation. While no uniqueness in terms of overall vegetation type(s)

is attributable to the general area in which the proposed access routes to these facilities would be

located, defining a route that results in least damage to all vegetation, and especially large

hardwood trees taken as being 60+ cm diameter at breast height (dbh) and large podocarp trees

taken as being 30+ cm dbh is a priority. This should be achievable because large hardwood and

podocarp tree densities across the recent terrace landforms the access road would mainly traverse

are very low. Appropriate final route delineation and ground survey will be key activities in

achieving this.

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Scheme effects on indigenous vegetation in Area 2 are considered minor.

Overall, effects of the Scheme on vegetation (classified as significant indigenous vegetation

under the Westland District Plan (WDC, 2002) and on any contribution to high natural heritage

values under the West Coast Conservation Management Strategy 2010 – 2020 (DOC, 2010) are

likely to be minor. This is based on the small amount of clearance (approximately 4.53 hectares)

that will occur within the surrounding contiguous area and within the combined indigenous

forest and shrubland cover of the Base Area of c. 396 hectares, combined with measures to be

implemented wherever practicable that avoid affecting important habitat components e.g. large

forest trees.

4. Suggested Approach to Effects Identified:

Risk Reduction and Monitoring

Weed incursion is a risk wherever earthmoving machinery is transported from areas where

weeds have been present, and in particular where gravel, and to a lesser extent rock, is carted in

to an area. While broadleaved herbaceous weeds that have wind dispersed seed are present in

low densities in areas without closed-canopy forest cover e.g., in grassed clearings and on

streamside zones, brushweed species are not established in Area 1 or Area 2 apart from a very

small zone of Ulex europaeus in an area of grassed alluvial flat adjacent to Macgregor Creek on

its true-left side that is grazed by cattle.

Earthmoving machinery should be thoroughly washed down prior to entering any part of Area 1

or Area 2 so as to reduce the risk of weed seed transport.

Recommended monitoring for weed establishment, in particular for Ulex europaeus but also for

other woody species e.g. Leycesteria formosa, should be undertaken at least annually and be

ongoing for all areas where gravel/rock has been carted in for Scheme components that comprise

the operational footprint.

For the headworks contractors’ facilities area, the access road to this and for any portion of the

tunnel portal exit apron decommissioned after construction is finished, annual monitoring for

weed establishment for a minimum of five seasons is recommended.

Remediation

Monitoring results will identify if there is any requirement for weed control in respect of any

Scheme component and the most appropriate control method to employ if required. If weed

control is found necessary anywhere in the Scheme project footprint it needs to be done as soon

as practicable in the most effective season for best control results for the species concerned, and

in any case prior to plants attaining seeding maturity.

Mitigation

Scheme design and location ensures that only a very small total area of indigenous vegetation is

affected. Infrastructure location largely avoids areas that carry mature podocarp/hardwood forest

or higher densities of large hardwood trees in those types where podocarp presence is reduced.

The access road/transmission line, intake access road and access road to the contractors’

facilities area traverse a variety of vegetation types and together incorporate most of the Scheme

12

project footprint as it affects vegetation. While potential effects are minor, they can be further

reduced by defining access road/transmission line, intake access road and access road to the

contractors’ facilities area routes that, subject to engineering considerations, result in least

damage to all vegetation, and especially large (60+ cm dbh) hardwood trees and podocarp trees

(30+ cm dbh). A component of this work would be to enumerate and mark all large trees within a

fixed width of the road formation centerlines and use these data to make any practicable road

alignment adjustments to avoid as many of these large trees as possible.

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1.0 Introduction

Westpower is proposing a run-of-river hydroelectric power scheme development in the Waitaha

River valley, the Waitaha Hydro Scheme (the Scheme) and have commissioned this report

describing terrestrial flora as a component of project planning.

The land on which the predominant amount of indigenous vegetation potentially affected by the

Scheme occurs is within Reserve 1672 and Section 1, Survey Office Plan 12094. These

landholdings are part of the Waitaha Forest conservation unit being Stewardship Land

administered by the Department of Conservation (DOC). The proposed activity sites are within

the Wilberg Ecological District, the general area of proposed activities being predominantly on

the true-right side of the Waitaha River upstream from Macgregor Creek to the upper end of the

Morgan Gorge (Appendix A, Map 1).

The Scheme consists of two sets of components in two distinct areas that will affect vegetation in

various ways. (N.B: the order of description here is not necessarily the order of any construction

activity):

Area 1: Headworks including construction and maintenance of:

a) Weir.

b) Water intake structures.

c) A tunnel portal entrance and short section of access road at the true-right upstream

end of Morgan Gorge, just below Kiwi Flat.

d) A short access road to a contractors’ facilities area and the area itself on a small

alluvial terrace on the true-right c. 250 metres upstream of Morgan Gorge entrance.

e) A flushing tunnel outlet in the Morgan Gorge.

A main tunnel will provide access from the lower Waitaha Valley to the various

headworks facilities. It will contain flushing basin structures and a penstock.

Construction and operation of these underground components will not affect

vegetation.

Area 2: Powerhouse and access road works including construction and maintenance of:

a) A heavy transport access road with power transmission line parallel, from the true left

side of Macgregor Creek in the lower valley to the site of powerhouse construction,

with roading extending on from the powerhouse to the tunnel portal exit site. N.B:

Vegetation description and effects assessment given in this report only pertain to that

part of the access road and transmission line shown on Appendix A, Map 3. The rest

of the access road and transmission line are expected to pass over private farmland

and possibly other Crown land and legal road. Vegetation effects, if any, on these

areas will depend on location of infrastructure. This is not finalised by Westpower at

time of preparation of this report.

14

b) A section of access road from the powerhouse to the tunnel portal exit.

c) A tunnel portal exit on the true-right of the Waitaha River, c. 1.5 km in straight line

distance below the nearest part of the area of headworks infrastructure (and tunneling

excavation itself, while not affecting vegetation, will require some area e.g. for

access, equipment and spoil handling/transfer).

d) Powerhouse and switchyard.

e) Penstock to convey water from the tunnel portal exit to the powerhouse.

f) Tailrace to carry water from the powerhouse back to the river.

g) Stopbank river protection for powerhouse, switchyard, a portion of access road and

penstock facilities.

h) Waterway training and flood protection at Alpha Creek (to protect the access road

and tailrace).

Indigenous vegetation of various types and cover densities occurs across the entire project area,

except the active riverbed and tributary streambed zones. Exotic plant species occur, in particular

on open riverbed/floodplain surfaces however incidence is relatively low and no other significant

historical anthropogenic modification has occurred at any site. Cattle grazing of a river flat area

upstream of Macgregor Creek appears to be sporadic. Possums and deer appear to be present in

low numbers and their impact on vegetation is likewise low.

The purpose of this report is to assess the effects of the Scheme on indigenous terrestrial

vegetation. In doing so this report:

Describes the main vegetation types present in the area and those potentially affected by

the Scheme.

Assesses the significance or uniqueness of the potentially affected vegetation types.

Describes and assesses the potential effects of the Scheme on indigenous terrestrial

vegetation.

Proposes mitigation and rehabilitation.

Describes predicted residual effect of the Scheme, overall, on vegetation.

This report presents the findings of a field assessment of vegetation undertaken in the periods

22/8/12 – 23/8/12 and 12/9/12 – 13/9/12 with a subsequent visit on 30/9/13. Fieldwork covered

land administered by DOC surrounding the proposed project footprint (construction and

operational areas combined) and the operational footprint i.e., permanent site occupancy once

construction is completed. It did not extend outside the Waitaha Forest conservation unit.

Vegetation type descriptions and species noted are based on visual assessment.

15

2.0 Location of Works

Construction activities are differentiated in two main areas in different parts of the lower

Waitaha Valley. For purposes of vegetation description and assessment these areas are hereafter

designated Area 1 (headworks) and Area 2 (including powerhouse and associated infrastructure,

access road and transmission line, and tunnel portal exit) as shown on Appendix A, Map 1, being

approximately 1.5 kilometres apart in straight line distance between closest proposed works

points.

Two streams that are shown on the NZTopo50 1:50,000 topographic mapping of the area but are

unnamed have been assigned in-house names by Westpower Ltd. to facilitate description of

Scheme components and their location. These are:

1. Granite Creek = the first unnamed stream shown on map sheet NZTopo50-BW17 south

of Macgregor Creek.

2. Alpha Creek = the second stream shown on map sheet NZTopo50-BW17 south of

Macgregor Creek.

N.B: The locations and distances given in Sections 2.1 and 2.2 are based on information

provided by Westpower as of November 2013 for capturing relevant data and forming vegetation

type descriptions for the various areas, however exact sites of construction of any of the

proposed works may vary slightly in terms of grid references and infrastructure distances given

in this report.

2.1 Headworks and Associated Works/Structures = Area 1

This is the area of proposed weir, water intake and associated structures, tunnel portal entrance,

access roading, contractors’ facilities area and flushing tunnel outlet (Appendix A, Map 1, Map 2

& Diagram 1) at the upstream end section of Morgan Gorge with the majority of construction

activity concentrated at c. NZTM E1415825; N5222160 at altitude of c. 240 m.a.s.l. Associated

with headworks construction is the proposed contractor’s facilities area on the nearest flat zone

of sufficient size on the same side of the river at c. NZTM E1416125; N5222050.

Tunneling will not impact on vegetation except in relation to tunnel entry portals and any

associated apron placement as noted above.

2.2 Access Road, Powerhouse and Associated Works/Structures = Area 2

This is the area for a tunnel portal exit and tunneling excavation, and for heavy transport access

road, power transmission line, powerhouse, switchyard, penstock, tailrace and stopbank

infrastructure (Appendix A, Map 1 & Map 3).

It extends from Macgregor Creek along the true-right side of the Waitaha River to c. 0.75 km

below Morgan Gorge.

16

3.0 Vegetation Description and Assessment Method – Area 1

Different vegetation types were identified to describe the principal variations present within

Area 1, and their extent. The types identified and described are sometimes quite clearly

demarcated by topographical change e.g. by a terrace dropover where a clear type change occurs

between higher and lower terraces, or between a recent alluvial flat and a forested margin.

However, this is not always the case and it is common to have varying degrees of intergradation

where topographical change is gradual and types merge. Also, the vegetation types were

determined by the main species within cover tiers (e.g. emergent, canopy, understory/shrub,

groundcover). It was not intended that the survey provide a complete catalogue of every species

present within a given type.

Vegetation assessment and description within the area and within vegetation types was on the

basis of observation by walkthrough, as terrain permitted, but where possible by transect across

the run of land. Use of any predefined sampling system (random or systematic) on all areas was

deemed impractical due primarily to difficulty of terrain particularly about the headworks sites.

Representative areas were covered based on interpretation of cover type from aerial photography

and field observation, with final delineation on the basis of checks and/or changes observed

during traverse. The result is a segregation of Area 1 into four vegetation types for descriptive

purposes. These are coded 1/1, 1/2, 1/3 and 1/4 (see Appendix A, Map 2).

3.1 Vegetation Type Descriptions for Area 1

Key landforms in Area 1 include hill foot slopes, terraces and terrace faces associated with these

and an area of relatively recent alluvial terrace. The principal forest types present here can be

broadly grouped as kamahi forest and seral forest using the classification described by James et

al., (1973), and as lowland forest and seral low forest under the classifications described by

Wardle, (1977, 1979 and 1991).

Note: Seral vegetation communities occur on sites prone to disturbance e.g. unstable gullies,

steep faces and on recent alluvial surfaces or waterway banks. Seral forest vegetation is typically

a mix of broadleaved indigenous hardwood tree species in a regeneration phase, along with

broadleaved indigenous shrub species and tree ferns.

Type 1/1 – Forest Margin/Riparian Mixed Ground Cover and Shrub Hardwood:

This type is a mixed moss/herb/fern/monocot and shrub hardwood low cover occurring in a

narrow strip (typically 3 – 6 metres wide) from the exposed gravel/sand/rock of the active river

bed to intergrade with the shrub margin of Vegetation Type 1/3 on the true left of the Waitaha

River and in a similar situation between active riverbed and margin of Vegetation Type 1/2 on

the true-right side. The majority is inundated at time of highest river flows.

Components of this cover type also occupy the bedrock surfaces of the Morgan Gorge between

the upper level of permanently scoured-clean rock and the lower margin of the Vegetation Type

1/3 shrub component that covers the Morgan Gorge sides. Seedlings of forest tree species e.g.

Metrosideros umbellata, Weinmannia racemosa, Podocarpus hallii, Dacrydium cupressinum and

Prumnopitys ferruginea occur occasionally in this type on the lower levels of Morgan Gorge

17

sides however the latter three podocarps do not appear on the river bank margins upstream of the

gorge.

Cover height range within Vegetation Type 1/1 is from ground surface to c. 1.5 metres at the

margins of this type where it intergrades with the other forest type shrub tiers. Species

comprising the higher cover include the shrubs Coriaria arborea, Coprosma rugosa, Hebe

salicifolia, Carpodetus serratus, Carmichaelia arborea, Olearia arborescens, Olearia ilicifolia

and Olearia avicenniifolia and monocots Phormium cookianum, Astelia fragrans and Cortaderia

richardii.

Ground cover species include mosses and thallose liverworts (Marchantia berteroana and

Monoclea forsteri), and Nertera depressa, Hydrocotyle moschata, Gingidia montana,

Hypochoeris radicata, Pratia angulata, Anisotome hastii, Acaena anserinifolia, Rubus parvus,

Raoulia tenuicaulis, Parahebe lyallii, Cirsium palustre, Cirsium arvense, Uncinia sp., Schoenus

pauciflorus, Poa spp., Agrostis dyeri, Festuca sp., Carex goyenii, Hierochloe novae-zelandiae,

Rytidosperma setifolium, and Blechnum sp. “black spot”. In damp zones under other cover or on

banks, Blechnum chambersii and Blechnum colensoi occur.

Figure 1 - Example of Vegetation Types 1/1 & 1/3:

Vegetation Type 1/1 occupies a narrow strip of c. 3 – 6 metres between the active Waitaha River

bed and the shrub hardwood margin of Vegetation Type 1/3 at the foot of the slope beyond the

river bank.

Type 1/2 - Regenerating Hardwood Shrub/Tree Mix With Low Podocarp Element:

This is an area of closed-canopy regenerating hardwood shrub and tree cover occupying a foot

slope face on the true-right of the Waitaha River extending upstream from the upper end of

Morgan Gorge for c. 150 metres. It extends c. 20 - 40 metres upslope to gradually intergrade

with Vegetation Type 1/3.

18

Canopy height is c. 6 - 8 metres with prevalent species being Griselinia littoralis (particularly

frequent), Weinmannia racemosa, Carpodetus serratus, Olearia ilicifolia, Olearia arborescens,

and Pseudowintera colorata. Occasional small (c. 30 cm diameter at breast height (dbh))

Podocarpus hallii stems are present in upper zones where an intergrade with Vegetation

Type 1/3 occurs.

Understory and shrub species include canopy species regeneration, Schefflera digitata,

Aristotelia serrata, Coprosma ciliata, Coprosma rhamnoides, Coprosma foetidisima, Coprosma

rotundifolia (in drier zones), Coprosma tayloriae, Coprosma colensoi, Myrsine divaricata,

Pseudopanax anomalus, occasional Quintinia acutifolia and scattered Prumnopitys ferruginea

and Podocarpus hallii seedlings. Cyathea smithii tree ferns occur throughout, while Dicksonia

squarrosa tree ferns are less prevalent. Carmichaelia arborea, Coriaria arborea and Hebe

salicifolia are present about margins.

Ground cover species are mosses including Hypopterygium novae-seelandiae, Mniodendron

dendroides, and Cyathophorum bulbosum, liverworts (Monoclea forsteri, Marchantia

berteroana and Schistochila sp.), Nertera vilosum, Nertera depressa, Viola filicaulis, Microlaena

avenacea, Uncinia uncinata, Astelia fragrans, Pneumatopteris pennigera, Asplenium bulbiferum,

Leptopteris superba, Blechnum sp. “black spot”, Blechnum fluviatile, Blechnum colensoi,

Metrosideros diffusa and scattered seedlings of canopy and shrub species.

Epiphytes include Asplenium flaccidum, Hymenophyllum spp., Trichomanes reniforme, and

Astelia fragrans.


Vegetation Type 1/2 occupies the foot slope face and upper terrace margins at the entry to

Morgan Gorge. Moss and herbaceous components of Vegetation Type 1/1 occur in a very narrow

strip on the large rocks between the active Waitaha River bed and the margin of Vegetation

Type 1/2.

19

Type 1/3 – Mature Podocarp/Hardwood Hill Forest:

This occurs on terraces, terrace faces and hill foot slope/side slope areas. The type is mature

podocarp/hardwood hill forest with the podocarp element more prevalent on terrace zones and in

particular along better-drained terrace edges, ridges and on higher-level slopes. In gully sides and

on faces, including the upper sides of Morgan Gorge, the podocarp element is reduced,

hardwoods forming the canopy.

Canopy emergents are principally Dacrydium cupressinum (dbh range typically 50 – 100+ cm),

and to lesser extent, Podocarpus hallii, Prumnopitys ferruginea and Metrosideros umbellata.

Libocedrus bidwillii trees typically 40 – 80 cm dbh, occur either as scattered individuals or in

small patches, in particular on the upper terrace surface on the true right of the Morgan Gorge,

and Podocarpus hallii trees appear more frequent here.

Canopy height is c. 16 – 22 metres in upper zones, reducing on lower faces and into Morgan

Gorge sides, where a hardwood canopy prevails and podocarps are absent or if present occur

rarely and are small. Weinmannia racemosa and Quintinia acutifolia are main canopy species

along with Metrosideros umbellata and occasional smaller stems of the emergent podocarp

species.

The understory/shrub tier includes canopy species regeneration and Pseudopanax crassifolius,

Pseudopanax colensoi, Pseudopanax anomalus, Pseudopanax simplex, Griselinia littoralis,

Carpodetus serratus, Pseudowintera colorata, Neomyrtus pedunculata, Phyllocladus alpinus,

Archeria traversii, Schefflera digitata, Coprosma lucida, Coprosma grandifolia, Coprosma

foetidissima, Coprosma rhamnoides, Coprosma tayloriae, Coprosma colensoi, Coprosma

linariifolia, and Coprosma ciliata. Ascarina lucida, Hedycarya arborea, Myrsine divaricata,

Coprosma rotundifolia and Neomyrtus pedunculata become more common in the shrub tier on

terraces and upper level slopes. Cyathea smithii and Dicksonia squarrosa tree ferns occur in

varying densities throughout.

Ground cover includes regeneration of canopy and understory species. Various mosses occur

(including Dendroligotrichum dendroides, Cyathophorum bulbosum, Hypopterygium novae-

seelandiae and Mniodendron dendroides) and liverworts are present (particularly Schistochila

spp.). Cover includes Lycopodium volubile, Nertera vilosum, Nertera depressa, Microlaena

avenacea, Uncinia spp., Astelia fragrans, Leptolepia novae-zelandiae, Lastreopsis hispida,

Pneumatopteris pennigera, Leptopteris superba, Blechnum chambersii, Blechnum sp. “black

spot”, Blechnum discolor, Phymatosorus diversifolius, Tmesipteris tannensis, Hymenophyllum

demissum, Hymenophyllum revolutum, Metrosideros diffusa, Luzuriaga parviflora, Poa colensoi,

Arthropodium candidum, Phormium cookianum and Gahnia sp. Patches of Histiopteris incisa

are present in open areas of gullies.

Climbers include Metrosideros diffusa, Metrosideros fulgens, and Rubus schmidelioides.

Epiphytes include Hymenophyllum revolutum, Hymenophyllum multifidum, Hymenophyllum

demissum, Phymatosorus diversifolius, Ctenopteris heterophylla, Asplenium flaccidum, Astelia

fragrans, Weinmannia racemosa and Quintinia acutifolia.

In zones above the scoured-clean bedrock in gorge areas, but prior to establishment of forest

shrub species as main cover, there is a zone of moss/liverwort and herbaceous and monocot

cover. This can vary in width from a few metres to ten metres or more. At least some parts of the

20

zone are affected by flooding at times of high river flow. Various moss species are common

along with liverworts (including Monoclea forsteri, Marchantia berteroana and Schistochila

sp.). Scattered seedlings of tree and shrub species occur e.g. Metrosideros umbellata, Hebe

salicifolia, Weinmannia racemosa, Coprosma rugosa, Carmichaelia arborea, Olearia

arborescens, Olearaia ilicifolia, and Olearia avicenniifolia. Otherwise, principal cover species

include Cortaderia richardii, Blechnum sp. “black spot”, Uncinia sp., Forstera tenella,

Parahebe lyallii, Agrostis dyeri, Hydrocotyle moschata, Geum leiospermum, Gunnera monoica,

Pratia angulata and Schoenus pauciflorus.


Vegetation Type 1/3 occupies terrace faces and upper terrace margins at the entry to Morgan

Gorge. Vegetation Type 1/1 extends in a strip between the active river bed and the margin of

Vegetation Type 1/3 on the hill face at left of the photograph.

21


Vegetation Type 1/3 on the terrace face at the true-left entry to Morgan Gorge. Vegetation Type

1/1 extends in a strip between the active river bed and the margin of Vegetation Type 1/3 at left

of the photograph and the moss/herb/monocot component rises around the bedrock of the gorge

entrance to occupy a margin c. 6 metres wide at the actual gorge entry.

Figure 5 - Example of Vegetation Type 1/3:

Vegetation Type 1/3 on the terrace edge and mid to upper face at the true-right entry to Morgan

Gorge – possible site of the tunnel portal entrance is approximately middle of photograph.

22


Vegetation Type 1/3 on the terrace edge and mid to upper face on the true-right of the Waitaha

River upstream of Morgan Gorge in the zone to be traversed by access roading to the

contractors’ facilities area and from the tunnel portal entrance to headworks weir/intake

infrastructure.


Example of Vegetation Type 1/1 grading to Vegetation Type 1/3 hardwood shrub component

cover on the true-left wall at the entrance to Morgan Gorge.

23

Figure 8 - Example of Vegetation Type 1/3 Shrub Component Cover in Morgan Gorge:

Vegetation Type 1/3 hardwood shrub cover on faces of Morgan Gorge. This grades uphill to

higher-stature hardwood canopy forest cover, with a minor podocarp element.


Vegetation Type 1/3 on lower hill foot slopes above the northern margin of Kiwi Flat (note that

this is not part of the proposed headworks area – it is included as an illustration of the stature and

composition of this type of hardwood footslope forest cover with very low to no incidence of

large podocarp emergents).

24

Type 1/4 - Shrub Hardwood, Successional:

This occurs on a relatively recent alluvial terrace extending from the active stream bed of the

Waitaha River true-right, north to the hill footslope margin, the terrace surface being c. 6 –

8 metres above the bed of the river and not showing signs of flood inundation. The type is dense,

closed-canopy hardwood shrub cover, typical canopy height being c. 3 – 5 metres.

Predominant canopy species include Olearia ilicifolia, Pseudopanax anomalus, Coprosma

ciliata, Coprosma tayloriae, Coprosma sp., Coprosma colensoi, Carmichaelia arborea and

Myrsine divaricata. Other canopy hardwoods of less frequent occurrence are Griselinia littoralis

(and very occasionally as an emergent), Pennantia corymbosa, Pseudowintera colorata and

Hebe salicifolia.

A dense understory tier includes all of the canopy species, with increased presence of

Pseudowintera colorata. Carpodetus serratus and Coprosma rotundifolia are understory

components.

Common ground cover species are the moss Hypopterygium novae-seelandiae, the thallose

liverworts Monoclea forsteri and Marchantia berteroana, ferns (Blechnum fluviatile,

Polystichum vestitum, Leptopteris superba, Blechnum colensoi and occasional young Cyathea

smithii tree ferns), the monocots Microlaena avenacea and Uncinia uncinata and the

broadleaved herbs Cardamine debilis and Epilobium pedunculare.

A frequent climber is Rubus schmidelioides.

Epiphytes are the ferns Ctenopteris heterophylla, Asplenium flaccidum, Grammitis magellanica,

Hymenophyllum demissum and Hymenophyllum revolutum. Mosses, in particular Weymouthia

mollis, are common.

25


Typical stature and composition of Vegetation Type 1/4 as seen along the edge of the alluvial

terrace above the active bed of the Waitaha River, northern margin of Kiwi Flat.


Typical stature and species composition of Vegetation Type 1/4.

26

4.0 Vegetation Effects In Area 1

The potential effects of each infrastructure component of the Scheme within Area 1 are

described below as to the size of affected area within each Vegetation Type, within riparian

margins if applicable, and in total.

All distance and area figures given in Tables 1 - 8 are indicative. The November 2013 Scheme

plans supplied by Westpower were used for the purpose of this assessment of effects. They may

be subject to variation depending on final location, access and construction requirements.

Areas given as construction, permanent and riparian (construction) in Tables 1 – 8 are not

additive. The construction area is the expected maximum area potentially affected by each

Scheme component and the construction total is an indication of the Scheme’s project footprint

as it pertains to vegetation effect. Areas given as permanent and riparian areas are sub-areas for

purposes of describing amount of vegetation clearance associated with a given Scheme

component. In the case of permanent areas these indicate the operational footprint of each

Scheme component and for the Scheme in total.

Where riparian areas are given in Tables 1 – 8 these are for streams >3metres wide where

provisions of the Proposed Regional Land and Water Plan (WCRC, 2013) and the Westland

District Plan (WDC, 2002) prescribe 10 metre riparian margin widths. Riparian areas are given

because activities affecting indigenous vegetation in riparian margins will require consideration

for regional and district planning provision purposes.

N.B. Streams 1 – 3 metres wide occur near the various areas of possible activity in Area 1 and

provisions of the Proposed Regional Land and Water Plan (WCRC, 2013) prescribe 10 metre

wide riparian margins for streams of this size if dominant slope angle is >12o and 5 metre wide

riparian margins otherwise. This requirement may add some area to the riparian area estimates

given, however the detailed field survey and mapping of small stream location was not a

component of work undertaken. The number and exact location of streams 1 – 3 metres wide that

are potentially affected will need to be determined for regional planning provision purposes,

although it is not considered that potential effects on vegetation will be any greater than already

assessed and considered.

An arbitrarily defined Base Area, being a zone encompassing Area 1 and Area 2, plus an

additional area representative of the vegetation types they exhibit is considered the Scheme’s

general locale. This Base Area is delineated by the 400 metre contour from the true-left margin

of Macgregor Creek at NZTM E1417875 N5225100 through to the Waitaha River true-right

margin in the Waitaha Gorge at NZTM E1419938 N5222050, thence by the true-right margin of

the Waitaha River and the true-left forest/bed margin of Macgregor Creek, as mapped on

NZTopo50-BW17. Where necessary the delineation around the Kiwi Flat area has been adjusted

with reference to 2010 - 2012 aerial photography to account for minor river channel changes and

vegetation colonisation since topographic map compilation. The Base Area is shown on

Appendix A, Map 5 and Appendix A, Map 6. It encompasses a total area of c. 436.2 hectares

comprising primarily indigenous vegetation (396 hectares) broadly classified as lowland

forest/seral low forest (James et al., 1973; Wardle, 1979). These 396 hectares of lowland

forest/seral low forest are the basis for percentage calculations in computing scale of vegetation

effects of the Scheme components and in total.

27

In assessing the level of potential effects of clearance of indigenous vegetation associated with

the Scheme a range of potential effects was considered based on a commonly available

continuum/guideline1. The scale of effects adopted for these purposes was:

Nil Effect.

Less than Minor - Negligible Effect.

Minor Effect.

More than Minor Effect.

Significant Effect.

For classifying potential effect of activities on vegetation in Area 1 a conservative approach was

adopted based, at the lowest end of the scale, on observed disruption to vegetation (i.e. landslip,

erosion etc.) that occurs naturally within the Scheme locale. Accordingly, the following scale is

applied:

Negligible Effect:

The total area of any temporary effect(s) associated with Scheme components in Area 12

is no more than 0.5 ha or 1.0% (whichever is greater) of the total area of similar

vegetation type assemblages in the locale;

AND

The total area permanently affected by Scheme components in Area 12 is no more than

0.5% of the total area of similar vegetation type assemblages in the locale.

Minor Effect:

The total area of any temporary effect(s) associated with Scheme components in Area 12

is no more than 1.0 ha or 2.0% (whichever is greater) of the total area of similar

vegetation type assemblages in the locale;

AND

The total area permanently affected by Scheme components in Area 12 is no more than

1.0% of the total area of similar vegetation type assemblages in the locale.

No Scheme effects were identified as being greater than negligible or minor relating to

vegetation clearance in terms of this assessment.

1 Source: Quality Planning website (www.qualityplanning.org.nz).

2 For the purposes of assessment of effects under Section 7.0 of this report, Area 2 replaces Area 1 in this

description.

28

4.1 Weir

The effect of weir works on vegetation is negligible, given that construction activities and the

weir structure are principally located in the active bed of the river on already exposed bedrock

with minimal vegetative cover. The area of activity is not deemed to be in riparian margin as it is

in the bed of the river. Vegetation that is present is Type 1/1 (see Appendix A, Diagram 1 and

Map 2).

Assuming permanent site occupancy area of the weir is 20 m2 as shown in Diagram 1, and a

construction-affected area of four times that, total potentially affected areas (combined

construction and permanent site occupancy by structure) by vegetation type are shown in

Table 1. As a maximum, 50% is deemed to carry some vegetation, the remainder being un-

vegetated bedrock and active river channel and therefore not included in the Table 1 areas.

Natural regeneration of current vegetation cover could be expected to occur relatively soon after

cessation of construction activities on all but the permanently occupied area, as scale and type of

disturbance is similar to that occurring at or about the site by natural causes e.g. minor slips and

major flood events and existing vegetation has established following these disturbances.

A further possible effect on vegetation could be that caused by any re-grading of the riverbed

after weir construction, however investigations into possible sedimentation buildup/change

indicate effects of the weir in its proposed location are unlikely to be substantial (Hicks, 2013). If

any small areas of existing vegetation were to be covered over by sediment aggradation or cut

away as new river channel(s) form as a result of weir effect, this process appears likely to be

confined to a minor portion of lower Kiwi Flat. It would be expected to be short term and would

not be inconsistent with the fluvial processes by which the flat has formed and is maintained

(Hicks, 2013). Natural regeneration would be expected in a matter of years, and this should

exhibit the range of species currently present, as it would if it were a site of natural disturbance.

Table 1: Weir Construction Distances and Potentially Affected Areas Within Vegetation Type.

Vegetation

Type

Distance

(m)

Construction

(ha)

Permanent

(ha)

Placement Within

Riparian Margins:

Distance (m)

Placement Within

Riparian Margins:

Construction (ha)

1/1 True-right side of

Waitaha River = 5

0.0025 0.0005 0.0 0.0

1/1 True-left side of

Waitaha River = 5

0.0025 0.0005 0.0 0.0

Totals 10 m x 5 m wide 0.0050 0.0010 0.0 0.0

4.2 Intake Channel

Effect of the intake channel on vegetation is negligible, given that construction activities and the

intake channel are principally on already exposed bedrock or boulder covered areas with

minimal vegetative cover. The area of activity is not deemed to be in riparian margin as it is in

the bed of the river. Vegetation that is present is Type 1/1 (Appendix A, Diagram 1 and Map 2).

29

Assuming permanent site occupancy area of the channel is c. 9.5 metres wide

average x 34 metres (accommodating cut of bedrock) and a construction-affected area of that

again, total potentially affected area is c. 650 m2. Area (combined construction and permanent

site occupancy by structure) by vegetation type is shown in Table 2. As a maximum, 50% of the

affected area is deemed to carry some vegetation, the remainder being un-vegetated bedrock and

boulder area and therefore not included in the Table 2 area.

Table 2: Intake Channel Potentially Affected Areas Within Vegetation Type.

Vegetation

Type

Construction

(ha)

Permanent

(ha)

Placement Within Riparian Margins:

Construction (ha)

1/1 0.0325 0.0163 0.0

Totals 0.0325 0.0163 0.0

4.3 Intake Structure and Intake Portal

The bedrock walls at the entrance to, and within Morgan Gorge, are scoured clean of vegetation

by flood events up to c. 8 meters. Sparse vegetation cover that is present above the clear zone

contains liverwort/moss, herbaceous and monocot components of Vegetation Type 1/1 in a

narrow band of a few meters wide before merging to Vegetation Type 1/3 shrub cover in the

gorge and with Vegetation Type 1/2 about and upstream of the gorge entrance.

Assuming permanent site occupancy area of the intake structure is c. 13 metres long x 8 metres

wide and a construction-affected area of double that again, total potentially affected area is

c. 312 m2. This work is likely to be within Vegetation Type 1/1 and Vegetation Type 1/2 in an

affected area ratio of c. 1/3 and 2/3 respectively. It is assumed the intake portal excavation will

be 6 metres x 6 metres. To this is added an allowance for side margin vegetation clearance effect

of 4 metres (each side) and top margin effect of 6 metres, giving an estimated total of 168 m2 and

that this will be both construction area and remain permanently occupied, probably affecting

Vegetation Type 1/2 and Vegetation 1/3 in similar amounts. Potentially affected areas (combined

construction and permanent site occupancy by structure) by vegetation type are shown in

Table 3. Overall effect of proposed works is likely negligible.

Part of the affected area is contained within what could be considered true-right riparian margin

of the Waitaha River. Vegetation types present in this area are not unique or distinguished

floristically from their counterparts not occupying the riparian strip. It is the arbitrary riparian

designation in the Proposed Regional Land and Water Plan (WCRC, 2013) and Westland

District Plan (WDC, 2002) of fixed-width distance from stream bank, not vegetation, that

distinguishes this zone – vegetation present would not preclude the activity here. Vegetation

recovery on any disturbed area not occupied by structures is likely to occur naturally, and exhibit

the range of species currently present.

30

Table 3: Intake Structure and Intake Portal Potentially Affected Areas Within Vegetation Types.

Vegetation

Type

Construction

(ha)

Permanent

(ha)


Construction (ha)

1/1 Intake 0.0100 0.0040 0.0

1/2 Intake 0.0210 0.0070 True-right side of Waitaha River = 0.0210

1/2 Portal 0.0084 0.0084 True-right side of Waitaha River = 0.0084

1/3 Portal 0.0084 0.0084 0.0

Totals 0.0478 0.0278 0.0294

4.4 Tunnel Portal Entrance

The tunnel portal entrance and an apron area will likely be located in Vegetation Type 1/2 and

Vegetation Type 1/3 in approximately equal proportions. The indicative dimensions of the tunnel

are 5 metres x 5 metres giving 25 m2

cleared (although this may need to be adjusted to suit

construction plant requirements). To this is added an allowance for side margin vegetation

clearance effect of 6 metres each side and top margin effect of 6 metres, giving an estimated total

of 187 m2 or 0.0187 ha, and that this will be both construction area and remain permanently

occupied. Potentially affected area (combined construction and permanent site occupancy by

structure) by vegetation type are shown in Table 4. Tunnel portal entrance siting should be

possible to avoid works in any riparian margin. Overall effect of proposed works on vegetation is

considered negligible.

Table 4: Tunnel Portal Entrance Potentially Affected Areas Within Vegetation Types.

Vegetation

Type

Construction

(ha)

Permanent

(ha)


Construction (ha)

1/2 0.00935 0.00935 0.0

1/3 0.00935 0.00935 0.0

Totals 0.01870 0.01870 0.0

4.5 Intake Access Road from Tunnel Portal Entrance to Intake Structures

The tunnel portal entrance is likely to be located on a relatively steep terrace face section. There

will be a requirement for some area of apron to allow equipment entry/egress and as a lead-in to

the access road. Based on Westpower planning information as of November 2013, a c. 10 metre

diameter permanent apron area is necessary, giving c. 80 m2. This is likely to affect similar areas

of Vegetation Type 1/2 and Vegetation Type 1/3.

Initial concept information (Appendix A, Diagram 1) shows c. 100 metres of access road

extending from the tunnel portal entrance apron to the intake structure area is needed (this is

indicative, with final length and width subject to survey and depending on portal location and

attaining suitable grade). If a 4 metre carriageway and 1 metre water-tabling allowance is applied

the road will occupy 500 m2, predominantly affecting Vegetation Type 1/2 (est. 90%), the

remainder being Vegetation Type 1/3.

31

A further zone of river protection and road combined at the toe of the slope is estimated to

involve an area of c. 300 m2 (c. 20 metres long paralleling the river x 15 metres wide as indicated

by Appendix A, Diagram 1), of which 30% is likely un-vegetated gravel and rock/boulders in the

river bed, meaning c. 210 m2

of vegetated or partially vegetated area affected, being

predominantly Vegetation Type 1/2 (est. 75%), the remainder being Vegetation Type 1/1. The

estimated 210 m2

affected area is predominantly, if not all, within the true-right riparian margin



designation in the Proposed Regional Land and Water Plan (WCRC, 2013) and Westland

District Plan (WDC, 2002) of fixed-width distance from stream bank, not vegetation, that

distinguishes this zone – vegetation present would not preclude the activity.

Allowing an additional affected area for construction (batter slopes, cuttings, fill zones) of a

similar amount again as the 0.058 ha permanently occupied area of road and tunnel portal

entrance apron added to the permanently occupied area of road, tunnel portal entrance apron and

river protection area of c. 0.079 ha gives a total construction-affected area of c. 0.137 ha.

Potentially affected areas by vegetation type are shown in Table 5. At this scale, effect of

proposed works on vegetation is considered negligible, vegetation recovery on any disturbed

area not occupied by structures is likely to occur naturally, and exhibit the range of species

currently present.

Table 5: Tunnel Portal Entrance Apron, Intake Access Road and River Protection Potentially

Affected Areas Within Vegetation Types.

Vegetation

Type

Construction

(ha)

Permanent

(ha)


Construction (ha)

1/3 Tunnel Portal Entrance Apron 0.0080 0.0040 0.0

1/2 Tunnel Portal Entrance Apron 0.0080 0.0040 0.0

1/3 Intake Access Road 0.0100 0.0050 0.0

1/2 Intake Access Road 0.0900 0.0450 True-right side of Waitaha River

20 m x 10 m strip = 0.0200

1/2 Protection/Road 0.0158 0.0158 True-right side of Waitaha River 0.0158

1/1 Protection/Road 0.0052 0.0052 True-right side of Waitaha River 0.0052

Totals 0.1370 0.0790 0.0410

4.6 Road to Contractors’ Facilities Area

Access to a proposed contractors’ facilities area on an alluvial terrace upstream of the tunnel

portal entrance requires formation of c. 130 metres of road sufficient to allow machinery

traverse. The final dimensions and location of this road are to be confirmed, but for purposes of

this assessment an approximate location is as per Appendix A, Map 2 and it is assumed that

carriageway and watertabling dimensions would be similar to those given above for the intake

access road, with an additional width allowance for cut/fill disturbance of 3 metres, therefore this

section will affect c. 1,040 m2, predominantly of Vegetation Type 1/4 (est. 75%) the remainder

being Vegetation Type 1/2. It may be possible to position this road outside (north) of the

Waitaha River riparian margin, however available area is narrow and may not allow complete

riparian margin avoidance. For vegetation effect assessment purposes and contingency, it is

assumed that c. 60 meters of the road distance will be partially in riparian margin, affecting

32

a 5 metre wide zone i.e., 300 m2 of riparian margin predominantly within Vegetation Type 1/4.

Vegetation present in the riparian area is not unique or distinguished floristically from its

counterpart not occupying the riparian strip. It is the arbitrary riparian designation in the

Proposed Regional Land and Water Plan (WCRC, 2013) and Westland District Plan

(WDC, 2002) of fixed-width distance from stream bank, not vegetation, that distinguishes this

zone – vegetation present would not preclude the activity here.

Potentially affected areas by vegetation type are shown in Table 6. This section of road will not

be required post-construction of the headworks infrastructure. The area can be rehabilitated or

left to regenerate naturally (see Section 10.0 re recommended mitigation). At this scale, and

considering the temporary nature of the site occupancy, effect of proposed works on vegetation

is within the scale of natural disturbance events in this environment and considered negligible.

Table 6: Road to Contractors’ Facilities Distances and Potentially Affected Areas Within

Vegetation Types.

Vegetation

Type

Distance

(m)

Construction

(ha)

Permanent

(ha)


Construction (ha)

1/2 40 0.0260 0.0 0.0

1/4 90 0.0780 0.0 True-right side of Waitaha River

60 m x 5 m strip = 0.030

Totals 130 0.1040 0.0 0.030

4.7 Contractors’ Facilities Area

A contractors’ facilities area of c. 2,000 – 2,200 m2 is proposed, to be located in the most

practicable siting on the first available flat zone of sufficient area upstream of Morgan Gorge

(Appendix A, Map 2). Final dimensions and location may be subject to change from those

shown, which have been used as preliminary input for effects assessment. The area is all within

Vegetation Type 1/4 and site configuration and placement should be able to be adjusted so as to

avoid works in the Waitaha River riparian zone. Vegetation types present in this riparian area are

not unique or distinguished floristically from their counterparts not occupying the riparian strip.

It is the arbitrary riparian designation of fixed-width distance from stream bank set by provisions

of the Proposed Regional Land and Water Plan (WCRC, 2013) and the Westland District Plan

(WDC, 2002), not the vegetation, which distinguishes this zone – vegetation present would not

preclude the activity.

This facilities area will not be required post-construction. The area can be rehabilitated or left to

regenerate naturally (see Section 10.0 re recommended mitigation). Considering the temporary

nature of the site occupancy, effect of proposed works on vegetation is considered negligible.

Table 7: Contractors’ Facilities Potentially Affected Area Within Vegetation Type.

Vegetation

Type

Construction

(ha)

Permanent

(ha)


Construction (ha)

1/4 0.220 0.0 0.0

Total 0.220 0.0 0.0

33

4.8 Flushing Tunnel Outlet

Settling basin and penstock intake structures are to be contained in excavations associated with

tunneling. The only effect on vegetation from this Scheme component will be requirement for an

outlet for a flushing tunnel discharge from the true-right wall of the Morgan Gorge back into the

river (see Appendix A, Diagram 1). The location for this is not fixed at time of preparation of

this report however a key requirement is that it is above any flood level. It would be on the stable

rock wall of the gorge. Assuming a 4 metre x 4 metre adit cross section and an allowance for

side margin vegetation clearance effect of 2 metres each side and top margin effect of 6 metres

(depending on vegetation cover/stature and substrate stabilisation requirements and area extent),

gives 80 m2, plus allowing a 10 metre x 4 metre ‘drop zone’ from tunnel base to river gives

40 m2, half of which is estimated to be un-vegetated bedrock of the lower gorge wall. All of the

above areas are assumed to be permanently occupied or affected by the Scheme, giving an

estimated total of 100 m2 with at least some vegetation and that this will comprise a minor

amount of Vegetation Type 1/1, c. 20%, and otherwise will be within Vegetation Type 1/3.

Overall effect of proposed works on vegetation is considered negligible.

Part of the affected area is contained within what could be considered true-right riparian margin



designation of fixed-width distance from stream bank, set by provisions of the Proposed

Regional Land and Water Plan (WCRC, 2013) and the Westland District Plan (WDC, 2002), not

the vegetation, which distinguishes this zone – vegetation present would not preclude the activity

here.

Table 8: Flushing Tunnel Outlet Potentially Affected Areas Within Vegetation Types.

Vegetation

Type

Construction

(ha)

Permanent

(ha)


Construction (ha)

1/1 0.002 0.002 True-right side of Waitaha River 0.002

1/3 0.008 0.008 True-right side of Waitaha River 0.008

Total 0.010 0.010 0.010

5.0 Other Observations Relating to Vegetation – Area 1

Generally, the state of vegetation of all types described above, both within the areas of proposed

works and the wider area, appears healthy and stable with the exception of change due to

naturally caused events e.g. occasional slips, changes in river channel location and windfall

zones, these being random and relatively infrequent. While possums and deer are present,

browse effect on indigenous vegetation at all sites appears very low. Sign indicates low possum

numbers in particular on the northern footslopes bordering Kiwi Flat and in the terrace below

Morgan Gorge, with very limited effect on vegetation in the Scheme area. Likewise for deer,

sign is sporadic and concentrated on the grassed and sandy areas of flats. Grazing is evident on

grassed clearing/flat areas, but appears sporadic and at a low level – this will be seasonally

variable, highest in spring and summer – however even then would not be of significant

detriment to the majority of indigenous vegetation present given the low deer population density.

Once into areas of shrub/bush cover deer movements disperse, and vegetation appears little

affected. No goats or goat sign were observed in this part of the Scheme area.

34

Exotic herbaceous weed species adapted for wind dispersal of seed (e.g. Cirsium spp.) are

present in low concentrations outside of forest areas e.g. along river and stream margins. No

brushweed species were observed in this part of the Scheme area.

6.0 Vegetation Description and Assessment Method - Area 2

The same strategy for field work and vegetation type delineation and description was used in

Area 2 as for Area 1 and the same survey objectives, descriptive aims and provisos apply. Area 2

(see Appendix A, Map 3) as assessed is a strip c. 1,950 metres long, that varies between c. 180

and 320 metres wide, along the true-right of the Waitaha River upstream of the true-left side of

Macgregor Creek. This does not imply that all of this width will be affected by any works, the

width being chosen arbitrarily to coincide with landform change where possible, but mainly to

cover sufficient area to provide some flexibility in final location of any access road and other

infrastructure without the requirement to extend the surveyed area eastward later if it were found

too narrow in the first instance.

Terrain allowed transect walk-through and representative areas were covered based on

interpretation of cover type from aerial photography, with splitting of types into sub-types in

some cases on the basis of changes observed during traverse.

The Area 2 survey zone is larger and encompasses a greater range of landforms than does

Area 1, in particular a sequence of alluvial terraces increasing in surface age with increased

height in an eastward progression, from the relatively recent alluvial flats adjacent to the current

active Waitaha River bed that have no closed forest species cover, to the higher terrace and hill

footslopes that carry mature podocarp/hardwood hill forest. Steeper terrace faces and footslopes

within this area have likely been subject to effects of shifts on the Alpine Fault resulting in

periodic disturbance via slips and colluvium deposition and exhibit a hardwood predominant

forest cover with very low incidence or absence of large podocarp trees. The result is a

segregation of Area 2 into twelve vegetation types for descriptive purposes. These are coded 2/1,

2/2, 2/3 etc. (Appendix A, Map 3).

There is no evidence of major modification to Area 2 vegetation by human activity e.g. clearance

or logging.

6.1 Vegetation Type Descriptions for Area 2

Predominant landforms in Area 2 are a set of relatively recent, low alluvial outwash terraces,

terrace faces and tributary stream fans at altitude of c. 140 – 160 m.a.s.l.

The principal forest types present here can be broadly grouped as kamahi forest (mature and

establishing or regenerating) and seral forest using the classification described by James et al.,

(1973), and as lowland forest (mature and establishing or regenerating) under the classifications

described by Wardle, (1977, 1979 and 1991).

35

Type 2/1 – Regenerating Podocarp/Hardwood Forest (Stage 1):

This occurs on a narrow, low, recent terrace that runs east to a vertical or near vertical terrace

face at the foot of which varying amounts of debris accumulation from face slipping form a

slope. The vegetation type is podocarp/hardwood in an early regenerational phase with tree ferns

a significant canopy element. Canopy height is c. 5 – 7 metres average and no large podocarp or

hardwood trees are present. It is typical of that observed on relatively young, well drained

surfaces.

Canopy cover is principally Weinmannia racemosa, Carpodetus serratus, Quintinia acutifolia,

Melicytis ramiflorus and with the tree ferns Cyathea smithii and Dicksonia squarrosa.

Occasional Prumnopitys ferruginea stems are present and scattered Dacrydium cupressinum

pole-sized (<20 cm dbh) stems are emergent above the hardwood component. Ripogonum

scandens occurs in the canopy in places (and in lower tiers).

The shrub tier includes canopy species regeneration and Podocarpus hallii, Ascarina lucida,

Hedycarya arborea, Myrsine australis, and Coprosma grandifolia. Cyathea smithii and

Dicksonia squarrosa tree ferns are abundant. Along margins, Carmichaelia arborea, Coprosma

rugosa, Olearia avicenniifolia, Olearia ilicifolia and Olearia arborescens are present.

Ground cover under the closed canopy is primarily litter with various mosses (including

Cyathophorum bulbosum and Hypopterygium novae-seelandiae) and liverworts (particularly

Monoclea forsteri, Hymenophyton flabellatum, and Schistochila spp.). Other cover includes

Asplenium bulbiferum, Asplenium flaccidum, Lastreopsis hispida, Blechnum sp. “black spot”,

Blechnum discolor, Hymenophyllum demissum, Grammitis billardieri, Nertera vilosum,

Microlaena avenacea, Uncinia uncinata, Astelia fragrans, Metrosideros diffusa, and scattered

seedlings/young plants of canopy and shrub tiers. Histiopteris incisa is present about margins.

Climbers include Metrosideros diffusa and occasional Ripogonum scandens patches occur,

principally in the sub canopy.

Epiphytes include Asplenium flaccidum, Grammitis spp., Hymenophyllum spp., Trichomanes

venosum, Tmesipteris tannensis, Phymatosorus diversifolius, Astelia fragrans, Weinmannia

racemosa and Quintinia acutifolia.

Within Type 2/1 there are occasional semi-clearings on slopes at the foot of the terrace, a result

of slips from above. Canopy, shrub and ground cover species present in the closed-canopy areas

are represented, however additional species observed in these areas and not noted in closed-

canopy areas include the shrubs Pennantia corymbosa and Coprosma tayloriae and as ground

cover components, Polystichum vestitum, Pteridium esculentum, Acaena anserinifolia, Lotus

pedunculatus, Cortaderia richardii and other mixed grass and thistle species.

The terrace face is included in Type 2/1. Cover consists of a similar hardwood species

assemblage to that which comprises the terrace canopy and shrub tiers along with Hebe

salicifolia and Griselinia littoralis, and prevalent ground cover species include Blechnum spp.

ferns observed on the terrace and Astelia fragrans, along with mosses and liverworts.

36


Vegetation Type 2/1 stature and composition on the low terrace in the foreground and on the

terrace face and regenerating slip in the background.

37

Type 2/2 – Grass, Sparse Shrub and Tree Fern Combination (Early Successional):

This occurs on a relatively recent alluvial flat that has a flood channel around its eastern margin

that has carried water in recent flood events. This channel is predominantly vegetated and not an

active portion of the river. Cover is typically between 0.5 and 0.8 metres high. Very occasional

regeneration of forest trees in seedling stage is present e.g. Metrosideros umbellata and

Weinmannia racemosa. Shrub cover consists of scattered individual stems or as small clumps.

Common species are Coprosma rugosa, Coprosma propinqua, Coprosma elatirioides,

Coprosma rubra, Pennantia corymbosa, Carmichaelia arborea, Pseudopanax crassifolius,

Carpodetus serratus, Hedycarya arborea, Myrsine divaricata, Ascarina lucida, Dracophyllum

longifolium, Pseudopanax simplex and the tree ferns Cyathea smithii and Dicksonia squarrosa.

Monocots and other ground cover species on the main flat and flood channel include abundant

Cortaderia richardii and scattered Astelia fragrans, Phormium cookianum, Blechnum discolor,

Blechnum sp. “black spot”, Blechnum fluviatile, Blechnum penna-marina, Hypolepis

rufobarbata, Histiopteris incisa, Metrosideros diffusa and Acaena anserinifolia. Grasses

(Agrostis tenuis, Poa spp., Festuca sp., Trisetum tenellum, Anthoxanthum odoratum, Holcus

lanatus) and mosses are intermingled along with other broadleaved herbaceous plants including

Cirsium arvense, Cirsium palustre, Ranunculus repens, Lotus pedunculata, Hydrocotyle novae-

zelandiae, Celmisia coriacea, Stellaria media, Plantago lanceolata, Hypochoeris radicata, and

Gunnera monoica.

Species present as ground cover along the flat margin with the active riverbed in what is a flood-

inundation zone include Marchantia berteroana, Acaena anserinifolia, Nertera ciliata, Gunnera

monoica, Raoulia tenuicaulis, Parahebe lyallii and Rytidosperma setifolium.


Vegetation Type 2/2 composition and cover of the river flat flood channel.

38


Vegetation Type 2/2 composition and cover on the river flat.

Type 2/3 – Mature Podocarp/Hardwood Hill Forest:

This occurs on elevated terrace and hill foot slope/side slope areas. The type is mature

podocarp/hardwood hill forest with the podocarp element more prevalent on terrace zones and in

particular along better-drained terrace edges and ridges. In gully sides and on faces the podocarp

element is reduced or absent, hardwoods forming the canopy.

Canopy emergents are principally Dacrydium cupressinum (dbh range typically 70 – 110+ cm),

and to lesser extent, Prumnopitys ferruginea and Metrosideros umbellata. Canopy height is c. 16

– 22 metres, with Weinmannia racemosa and Quintinia acutifolia the main canopy species along

with smaller stems of the emergent podocarps.

The understory/shrub tier includes canopy species regeneration and Podocarpus hallii, Ascarina

lucida, Hedycarya arborea, Myrsine divaricata, Neomyrtus pedunculata, Pseudopanax

crassifolius, Griselinia littoralis, Pseudowintera colorata, Coprosma foetidissima, Coprosma

rhamnoides, Coprosma tayloriae, and Coprosma ciliata. Cyathea smithii and Dicksonia

squarrosa tree ferns are common.

Ground cover is primarily litter with various mosses (including Dawsonia superba,

Cyathophorum bulbosum, Hypopterygium novae-seelandiae and Mniodendron dendroides),

liverworts (particularly Schistochila spp.) and occasional patches of Lycopodium volubile. Other

cover includes Nertera vilosum, Nertera depressa, Nertera ciliata, Microlaena avenacea,

Arthropodium candidum, Uncinia sp., Astelia fragrans, Trichomanes reniforme, Lastreopsis

hispida, Sticherus cunninghamii, Blechnum sp. “black spot”, Blechnum discolor,

Hymenophyllum demissum, Hymenophyllum revolutum, Grammitis billardieri, Metrosideros

diffusa, and scattered seedlings/young plants of canopy and shrub tiers.

39

Climbers include Ripogonum scandens, Freycinetia baueriana subsp. banksii, Metrosideros

diffusa, Metrosideros fulgens, Metrosideros perforata and Rubus cissoides.

Epiphytes include Asplenium flaccidum, Grammitis spp., Hymenophyllum revolutum,

Hymenophyllum spp., Trichomanes venosum, Tmesipteris tannensis, Phymatosorus diversifolius,

Astelia fragrans, Weinmannia racemosa and Quintinia acutifolia.

Type 2/3A – Mature Hardwood Forest, Podocarp Element Reduced/Absent:

This is a variation of Type 2/3 occurring particularly on foot slope faces in the northern portion

of Area 2. The main difference is that the emergent podocarp element typical of Type 2/3 is

significantly reduced and absent in places, the canopy height is lower (est. 8 – 12 metres on

densest-cover faces) and has a higher proportion of Cyathea smithii and Dicksonia squarrosa

tree ferns and Ripogonum scandens and Freycinetia baueriana subsp. banksii thickets.

Figure 15 - Example of Vegetation Types 2/3 & 2/3A:

Typical composition and stature of Vegetation Type 2/3A on face terrain, grading into

Vegetation Type 2/3 in higher ridge areas.

Type 2/3B – Poorly Drained Lower Stature Hardwood Forest with Minor Presence of

Dacrycarpus dacrydioides:

This is a relatively small area on a slight terrace c. 3 metres high along its western margin. It is

adjacent to Macgregor Creek on its northern edge and at the same level, exhibiting poor drainage

and recent alluvial deposits from Macgregor Creek overflow. The vegetation here grades to

Vegetation Type 2/3A, however key differences are lower canopy height (c. 6 – 10 metres),

extremely dense thickets of Ripogonum scandens and Freycinetia baueriana subsp. banksii as

canopy cover in conjunction with hardwoods as per Vegetation Type 2/3A and a low incidence

of Dacrycarpus dacrydioides as saplings and pole sized stems and a single stem of tree size

40

estimated at c. 60 cm dbh. The few emergent Dacrydium cupressinum trees present show

advanced dieback, likely a result of sedimentation and impeded drainage due to the gravel and

silt deposition by Macgregor Creek.

Figure 16 - Example of Vegetation Type 2/3B:

Vegetation Type 2/3B occurs at middle-left of the picture adjacent to Macgregor Creek. The

relatively small area of this type is evident as naturally occurring dieback of hardwoods and

emergent Dacrydium cupressinum trees along the true-left creek margin.

Type 2/4 – Regenerating Podocarp/Hardwood Forest (Stage 2; Average Canopy Height >

Stage 1):

This occurs on two sets of recent terrace surfaces (slightly higher and older than that supporting

Vegetation Type 2/1 cover). One smaller area is between Macgregor Creek and Granite Creek –

this intergrades eastward with Type 2/3 and 2/3A. A larger area extends in a band from Granite

Creek south to about NZTM E5224240; N1415340 and east to the foot of a terrace face beyond

which it intergrades upslope with its Vegetation Type 2/4A sub-type in places and otherwise

Vegetation Type 2/3. Vegetation Type 2/4 is podocarp/hardwood forest in a regenerational phase

slightly more advanced than that of Vegetation Type 2/1. Canopy height is typically c. 6 – 10

metres with tree ferns a significant component in places. No large podocarp or hardwood trees

are present.

Canopy cover is principally Weinmannia racemosa and the tree ferns Cyathea smithii and

Dicksonia squarrosa. Other canopy hardwoods of less frequent occurrence are Quintinia

acutifolia, Carpodetus seratus, Griselinia littoralis, and Pennantia corymbosa. Occasional

Prumnopitys ferruginea and Dacrydium cupressinum pole-sized (< 20 cm dbh) stems are

emergent above the hardwood component, mainly along the western margin of this type.

Ripogonum scandens occurs in the canopy in places (and in lower tiers).

41

The shrub tier includes canopy species regeneration and tree ferns along with Pseudopanax

crassifolius, Pseudopanax colensoi, Ascarina lucida, Hedycarya arborea, Melicytus ramiflorus,

Coprosma rotundifolia, Coprosma ciliata, Coprosma tayloriae, and Pseudowintera colorata.

Along margins Coprosma species are prevalent, including those internal to the forest plus

Coprosma propinqua and Coprosma elatirioides.

Ground cover species include the mosses Cyathophorum bulbosum, Hypopterygium novae-

seelandiae and Mniodendron dendroides, liverworts (particularly Schistochila spp. and

occasional Monoclea forsteri), Blechnum sp. “black spot”, Blechnum discolor, Blechnum

fluviatile, Blechnum colensoi, Lastreopsis hispida, Asplenium bulbiferum, Asplenium polyodon,

Uncinia spp., Nertera vilosum, Nertera depressa, Microlaena avenacea and Metrosideros

diffusa.

Climbers include Ripogonum scandens, Rubus cissoides and Metrosideros diffusa.

Epiphytes include Dendrobium cunninghamii, Asplenium flaccidum, Grammitis spp.,

Hymenophyllum spp., Trichomanes venosum, Rumohra adiantiformis, Astelia fragrans,

Melicytus ramiflorus, Weinmannia racemosa and Quintinia acutifolia.


Typical Vegetation Type 2/4 composition and cover – i.e. the hardwood/tree fern regeneration

extending from the grassed flat margin back to the foot of the ridge in middle distance where it

grades into Vegetation Type 2/3.

42

Type 2/4A - Regenerating Podocarp/Hardwood Forest (Stage 3; Average Canopy Height >

Stage 2):

This is a variation of Vegetation Type 2/4 occurring on a slightly more elevated (3 – 4 metre

higher) terrace. The main difference is that canopy height is greater (est. 14 metres average) and

with Weinmannia racemosa trees of 60 – 100+ cm dbh scattered through as emergents between

18 and 24 metres tall.

Type 2/5 – Regenerating Podocarp/Hardwood Tree and Shrub Admixture With Occasional

Emergent Trees:

Occupying the northern c. 2/3 of a low outwash terrace/ex alluvial flat, this area of

podocarp/hardwood forest is in early stages of regeneration. While there are occasional small

clearings, the canopy is closed over the majority of the area and is c. 8 – 12 metres high,

however drops in height and thins with progression southward to become c. 6 – 7 metres as it

intergrades with Vegetation Type 2/6 and tree ferns become an increasing proportion of cover

here.

Scattered larger Weinmannia racemosa trees of 40 - 80 cm dbh, occasional small Dacrydium

cupressinum trees of c. 30 cm dbh, and very occasional Metrosideros umbellata trees (largest

observed was est. 90 cm dbh) occur as canopy emergents.

Predominant canopy species is Weinmannia racemosa, along with the tree ferns Cyathea smithii

and Dicksonia squarrosa. Carpodetus serratus, Griselinia littoralis, Pseudopanax crassifolius,

Dacrydium cupressinum and Prumnopitys ferruginea are less frequently occurring components.

Understory and shrub tier species include those of the canopy, and Pseudowintera colorata,

Hedycarya arborea, Melicytus ramiflorus, Ascarina lucida, Pennantia corymbosa, Quintinia

acutifolia, Pseudopanax colensoi, Coprosma rhamnoides, Coprosma rotundifolia, Coprosma

tayloriae and Coprosma sp. Very occasional Dacrycarpus dacrydioides saplings were observed.

Along margins, scattered Carmichaelia arborea and Coprosma propinqua are present.

Ground cover species include the mosses Cyathophorum bulbosum, Hypopterygium novae-

seelandiae and Mniodendron dendroides, liverworts (Schistochila spp. and occasional Monoclea

forsteri), occasional clusters of Polystichum vestitum, and Blechnum fluviatile, Lastreopsis

hispida, Nertera vilosum, Nertera depressa, Cardamine debilis, Stellaria media, Uncinia spp.,

Microlaena avenacea, Acaena anserinifolia and Metrosideros diffusa.

Climbers include sparse Ripogonum scandens, Rubus cissoides, Rubus schmidelioides and

Metrosideros diffusa.

Epiphytes observed were Asplenium flaccidum, Tmesipteris tannensis, Grammitis spp.,

Hymenophyllum spp., Trichomanes venosum, Rumohra adiantiformis, Asplenium flaccidum,

Melicytus ramiflorus, Weinmannia racemosa and Quintinia acutifolia.

43


Vegetation Type 2/5 composition and cover at the southern end of its area, grading into

Vegetation Type 2/6.

Type 2/6 – Regenerating Hardwood Tree/Shrub/Tree Fern Admixture with Grassed Clearings:

This type grades from Type 2/5 and occupies the southern c. 1/3 of the same low outwash

terrace/ex alluvial flat. Regeneration of hardwood forest tree and shrub species, tree ferns and

colonising shrub species occur as scattered individual stems or as small closed-cover stands

interspersed with variable-sized grassed clearings. A moderate amount of recent and old deer

sign (grazing and droppings) was evident in these clearings however there was very little sign of

browse on other vegetation (shrubs, trees etc.).

Predominant tree and shrub species are Griselinia littoralis, Weinmannia racemosa, Melicytis

ramiflorus, Pseudowintera colorata, Pseudopanax crassifolius, Pseudopanax simplex,

Carpodetus serratus, Hedycarya arborea, Myrsine divaricata, Ascarina lucida, Pennantia

corymbosa, Coprosma rugosa, Coprosma rubra, Coprosma elatirioides, Coprosma propinqua,

Coprosma tayloriae, and the tree ferns Cyathea smithii and Dicksonia squarrosa. Occasional

Podocarpus hallii saplings were observed.

Monocots and other ground cover species include regeneration of the tree and shrub species

along with Cortaderia richardii and scattered Astelia fragrans, Blechnum sp. “black spot”,

Blechnum fluviatile, Histiopteris incisa, Pteridium esculentum, Paesia scaberula, Polystichum

vestitum, Ctenopteris heterophylla, Metrosideros diffusa, Cardamine debilis, Acaena

anserinifolia and Stellaria media.

Climbers include Rubus cissoides, Rubus schmidelioides, Metrosideros diffusa and Metrosideros

perforata.

44

Epiphytes, mainly occurring on tree ferns, include Asplenium flaccidum, Tmesipteris tannensis,

Grammitis spp., Hymenophyllum spp., Trichomanes venosum, Rumohra adiantiformis, Astelia

fragrans, Melicytus ramiflorus, Weinmannia racemosa and Quintinia acutifolia.

Grasses and broadleaved herbaceous plants in clearings include Agrostis tenuis, Poa sp.,

Anthoxanthum odoratum, Holcus lanatus, Ranunculus repens, Lotus pedunculata, Taraxacum

officinale, Cirsium arvense, Cirsium palustre, Hypochoeris radicata, and Plantago lanceolata.

Species present as ground cover along the margin with the active riverbed in what is a flood-

inundation zone are as for Vegetation Type 2/2 but with increased presence of Cortaderia

richardii.


Emergent trees and the higher canopy of Vegetation Type 2/5 are shown in the background, with

typical Vegetation Type 2/6 composition and cover in the foreground.

45


Typical Vegetation Type 2/6 composition and cover – grassed clearings interspersed with shrub

hardwood and tree fern clusters.

Type 2/7 – Grassed Alluvial Flat with Sparse Colonising Hardwood Shrub Presence:

This type occurs on a relatively recent alluvial flat. Colonising shrub species occur as individuals

or small clusters interspersed throughout a predominantly grassed area. It differs from

Vegetation Types 2/2 and 2/6 in that it has a higher proportion of open grass sward cover.

Shrub and young tree species include Coprosma rugosa, Coprosma propinqua, Coprosma

areolata, Coprosma sp., Pennantia corymbosa, Carpodetus serratus, Aristotelia serrata, and

Myrsine divaricata.

Grasses and broadleaved herbaceous plants in main clear zones include Agrostis tenuis, Poa

spp., Anthoxanthum odoratum, Festuca sp., Holcus lanatus, Trisetum tenellum, Ranunculus

repens, Lotus pedunculata, Taraxacum officinale, Hypochoeris radicata, Trifolium repens,

Cirsium arvense, Cirsium palustre, Plantago lanceolata, Hydrocotyle novae-zelandiae and

Acaena anserinifolia.

Other ground cover species occurring singly or as patches are Paesia scaberula, Polystichum

vestitum, Blechnum sp. “black spot”, Blechnum discolor, Histiopteris incisa and Cortaderia

richardii.

Scattered Ulex europaeus plants have established about the northern margin near the outwash fan

of Macgregor Creek.

46


Typical Vegetation Type 2/7 composition and cover.

Type 2/8 – Tree Fern/Hardwood Shrub/Monocot with Low Incidence of Dacrycarpus

dacrydioides:

A restricted area on the immediate true-left of Macgregor Creek, this has been affected by

shingle and rock deposits at times of flooding. Cover varies from c. 3 – 4 metres high where it

grades to Vegetation Type 2/3B to the north and to Vegetation Type 2/4 to the south. Species

composition is similar to Vegetation Type 2/4 re hardwood shrubs and tree ferns. There is a more

open area closer to Macgregor Creek, where Dicksonia squarrosa and Cyathea smithii tree ferns

are prevalent, along with scattered Coprosma spp. and Rubus spp. and Metrosideros diffusa

clusters are common on supporting vegetation. Occasional Dacrycarpus dacrydioides seedlings

and saplings are present. Cortaderia richardii is frequent in the open and Acaena anserinifolia is

present on gravel areas.

47


Typical Vegetation Type 2/8 composition and cover is shown in the mid foreground.

Type 2/9 – Mixed Ground Cover/Shrub Hardwood Riparian:

This occupies narrow (10 – 20 metres wide) strips on either side of Alpha Creek, and is typical

of vegetation colonising relatively recent and/or disturbed rock and alluvial deposit surfaces in

forested valley catchments.

Hardwood tree regeneration is Weinmannia racemosa and Metrosideros umbellata. Shrub

species include Coriaria arborea, Hebe salicifolia, Carpodetus serratus, Aristotelia serratus,

Ascarina lucida, Fuchsia excorticata, Carmichaelia arborea, Coprosma spp., Olearia ilicifolia

and Olearia avicenniifolia.

Common ground cover species are mosses, lichens, Lycopodium volubile, Blechnum sp. “black

spot”, Blechnum penna-marina, Paesia scaberula, Lastreopsis hispida, Cortaderia richardii, and

scattered Lotus pedunculata, grasses, broadleaved herbs e.g. Hypochoeris radicata, Acaena

anserinifolia and Nertera depressa.

48


Typical Vegetation Type 2/9 composition and cover is shown in the foreground.

7.0 Vegetation Effects in Area 2

The potential effects of each infrastructure component of the Scheme within Area 2 are

described below as to the size of affected area within each Vegetation Type, within riparian

margins if applicable, and in total.

All distance and area figures given in Tables 9 - 15 are indicative. The November 2013 Scheme

plans supplied by Westpower were used for the purpose of this assessment of effects. They may

be subject to variation depending on final location, access and construction requirements.

Areas given as construction, permanent and riparian (construction) in Tables 9 – 15 are not

additive. The construction area is the expected maximum area potentially affected by each

Scheme component and the construction total is an indication of the Scheme’s project footprint

as it pertains to vegetation effect. Areas given as permanent and riparian areas are sub-areas for

purposes of describing amount of vegetation clearance associated with a given Scheme

component. In the case of permanent areas these indicate the operational footprint of each

Scheme component and for the Scheme in total.

Where riparian areas are given in Tables 9 – 15 these are for streams >3metres wide where

provisions of the Proposed Regional Land and Water Plan (WCRC, 2013) and the Westland

District Plan (WDC, 2002) prescribe 10 metre riparian margin widths. Riparian areas are given

because activities affecting indigenous vegetation in riparian margins will require consideration

for regional and district planning provision purposes. N.B. Streams 1 – 3 metres wide occur near

the various areas of possible activity in Area 2 and provisions of the Proposed Regional Land

and Water Plan (WCRC, 2013) prescribe 10 metre wide riparian margins for streams of this size

if dominant slope angle is >12o and 5 metre wide riparian margins otherwise. This requirement

49

may add some area to the riparian area estimates given, however the detailed field survey and

mapping of small stream location was not a component of work undertaken. The number and

exact location of streams 1 – 3 metres wide that are potentially affected will need to be

determined for regional planning provision purposes, although it is not considered that potential

effects on vegetation will be any greater than already assessed and considered.

The same criteria apply to Area 2 as for Area 1 (refer Section 4.0) in assessing scale of Scheme

effects on vegetation.

7.1 Tunnel Portal Exit and Construction Apron

The final site of the tunnel portal exit may be subject to change but for purposes of this

assessment it is taken to be at or about c. NZTM E1415324; N5223550, consistent with the

November 2013 Scheme plans. Removal of vegetation will be required across the east-west

width of the footslope at this site to access the foot of the main terrace riser, and for some

distance north and south of the tunnel portal area, to give machinery access and allow room for

construction, equipment, and spoil handling. Final area requirements are not defined on the

ground at time of this assessment. For purposes of vegetation assessment, an indicative affected

area is assumed to be c. 40 metres east-west and 50 metres north-south so as to give sufficient

room for construction activities and to accommodate the penstock and access way in this area

after tunnel construction is complete. In addition, vegetation on the vertical terrace face will be

removed for the actual tunnel portal and excavation. An estimate of area affected is based on an

8 metre wide x 7 metre high tunnel, with side margins of 8 metres each side for the height of the

terrace face (estimated as 20 metres) and top margin of 8 metres width, also to the top of the

terrace face. This gives a potentially affected area of c. 480 m2.

The larger tunnel portal exit dimensions of 8 metres x 7 metres are required as this is a single

portal as opposed to the separate portals (intake portal and tunnel portal entrance) in the

headworks area. Table 9 gives potentially affected areas by vegetation type.

It is unlikely that the full width of area required for construction purposes will need to remain

permanently cleared of vegetation and it is assumed that 33% of the area could regenerate or be

re-vegetated after cessation of construction (see Section 10.0 below, re recommended

mitigation). Vegetation effect is considered negligible.

Table 9: Tunnel Portal Exit and Construction Apron Potentially Affected Area Within

Vegetation Types.

Vegetation

Type

Construction

(ha)

Permanent

(ha)

Placement Within Riparian

Margins:

Construction (ha)

2/1 Tunnel Portal Exit 0.048 0.048 0.0

2/1 Tunnel Portal Exit Apron 0.100 0.066 0.0

2/2 Tunnel Portal Exit Apron 0.100 0.066 0.0

Totals 0.248 0.180 0.0

50

7.2 Access Road and Transmission Line

The proposed access road location is approximately as shown on Appendix A, Map 3. This

route was not defined on the ground at time of preparation of this report, so actual affected areas

within vegetation types cannot be confirmed however variation from figures given herein is

expected to be negligible (if any). A maximum expected width for the access road and

transmission line where these are adjacent is 20 metres. In the case of transmission line pole

location, this is intended to follow the road alignment wherever practicable and where straight-

line distances are reasonable but may depart from the road alignment (subject to topographical

suitability and large tree avoidance considerations) to reduce angles in the line. Where this

occurs, some small area of vegetation clearance would be required at individual pole sites that

are additional to the road width, however this will likely be concomitant with a reduction in

cleared zone width that accommodates only the road in such departure zones.

Therefore, for potentially affected area calculations it is assumed an average width of affected

area is 15 metres for road and transmission line combined, for the c. 1,698 metre route distance

as indicatively mapped (Appendix A, Map 3). The actual location of the road may be adjusted

subject to engineering considerations, to avoid large trees where possible, or to facilitate

alignment. N.B: a ‘corridor’ zone is shown (Appendix A, Map 3) in which that possible

adjustment of the maximum 20 metre wide access road/transmission line location may occur –

this ‘corridor’ zone does not delineate the final potentially affected area of formed road.

Given the above, the most likely vegetation types affected and areas of each are shown in

Table 10. Vegetation types present in riparian margins in this area are not necessarily unique or

distinguished floristically from their counterparts not occupying a riparian strip. It is the arbitrary

riparian designation of fixed-width distance (10 metres) from stream bank contained in the

Proposed Regional Land and Water Plan (WCRC, 2013) and Westland District Plan

(WDC, 2002), not vegetation, that distinguishes these zones – vegetation present would not


It is likely that the majority of area required for access road/transmission line construction

purposes will need to remain permanently cleared of vegetation (possibly 95% of the total

construction-affected area) to enable continued access and facility inspection and maintenance,

however total construction-affected area, at c. 2.547 hectares, is 0.6% of the Base Area

vegetation and considered negligible.

51

Table 10: Access Road Distances and Potentially Affected Areas Within Vegetation Types.

(Note: Table lists individual segments within vegetation type starting at Macgregor Creek and proceeding south (see Appendix A, Map 3)).

Vegetation

Type

Distance

(m)

Construction

(ha)

Permanent

(ha)

Crossings of Riparian Margins:

Distance (m)

Crossings of Riparian Margins:

Construction (ha)

2/8 132

0.1980 0.1881 0.0 0.0

2/3B 120 0.1800 0.1710 True-left side of Macgregor Creek

10.0

True-left side of Macgregor Creek

0.015

2/3A 144

0.2160 0.2052 0.0 0.0

2/3 54

0.0810 0.0770 0.0 0.0

2/9 48 0.0720 0.0684 Both sides of Granite Creek

20.0

Both sides of Granite Creek

0.030

2/3 108

0.1620 0.1539 0.0 0.0

2/4A 306

0.4590 0.4361 0.0 0.0

2/4 714 1.0710 1.0175 Both sides of Alpha Creek

(Distance accounted for under separate waterway

training/flood protection works at this site, see

Section 7.3, below, so not included again here)

Both sides of Alpha Creek

(Area accounted for under separate waterway

training/flood protection works at this site, see

Section 7.3, below, so not included again here)

2/3 36 0.0540

0.0513 0.0

0.0

2/1

36 0.0540 0.0513 0.0 0.0

Totals 1698 2.5470 2.4198 30.0 0.045

52

7.3 Waterway Training and Flood Protection – Alpha Creek

November 2013 Scheme plans provided by Westpower show the indicative area within which

flood protection works are proposed on a portion of Alpha Creek where the creek exits the

terrace/terrace face to the east where, until that point, it is in an incised/defined channel, but

after exiting the terrace can flow in a number of directions. It is proposed to control and train

any flow to a defined channel within the creek. Proposed works may include the development

of a single, defined channel (including stopbanks on one or two sides) of the lower portion of

Alpha Creek to train and divert flows, in particular flood flows, to a single flow path. The aim

of the works is to prevent large flood flows and associated alluvium affecting the tailrace

and/or access road and to contain the stream at the access road crossing point. The potentially

affected zone is shown on Appendix A, Map 3. It involves a c. 150 metre strip commencing c.

30 metres north of the current stream confluence with the Waitaha River and extending east in

a direct line up the stream outwash fan, with c. 135 metres of the total distance being

vegetated. Width of this potentially affected area is c. 25 metres giving a maximum area of

3,375 m2, all of which is within Vegetation Type 2/4.

This work will involve crossing a 25 metre x 10 m portion of riparian vegetation on the true-

right of the Waitaha River. Provisions of the Proposed Regional Land and Water Plan

(WCRC, 2013) and the Westland District Plan (WDC, 2002) prescribe 10 metre riparian

margin widths for streams >3 metres wide whether permanently flowing or not. These

provisions apply to Alpha Creek. The eastern-most c. 75 metres of the proposed flood

protection work zone is likely to involve the entire 10 meter wide riparian margin on each

side of Alpha Creek, and may involve slightly more depending on final route location relative

to the current stream channel(s). Vegetation types present in riparian margins in this area are

not necessarily unique or distinguished floristically from their counterparts not occupying a

riparian strip. It is the arbitrary riparian designation of fixed-width distance (10 metres) from

stream bank contained in the Proposed Regional Land and Water Plan (WCRC, 2013) and

Westland District Plan (WDC, 2002), not vegetation, that distinguishes these zones –

vegetation present would not preclude the activity.

The current stream course(s) run beneath closed canopy forest cover and it is expected that

regeneration of the range of indigenous species currently present would occur naturally and it

is possible that at least 50% of the construction-affected area could become revegetated. This

is likely to also apply to a similar portion of any riparian margin area affected by construction.

The scale of vegetation clearance involved in this Scheme component is within that of

naturally occurring disturbance events e.g. slips and stream channel changes in this locality

and environment. Evidence of these occurrences is the set of two different-aged but relatively

recent slips, one regenerating, the other fresh, in this same stream c. 400 metres upstream of

its confluence with the Waitaha River (see Appendix A, Map 3). Areas potentially affected by

this Scheme component are shown in Table 11. Vegetation effects are considered negligible.

53

Table 11: Waterway Training and Flood Protection Works (Alpha Creek) Distance and

Potentially Affected Area Within Vegetation Type.

Vegetation

Type

Distance

(m)

Construction

(ha)

Permanent

(ha)

Placement Within

Riparian Margins:

Distance (m)

Placement Within

Riparian Margins:

Construction (ha)

2/4 135 0.3375 0.1688 True-right side of Waitaha

River

10


2 x 75 m long parallel

strips =

75

True-right side of Waitaha

River

25 m x 10 m strip = 0.025


75 m x 2 x 10 m

strips =

0.150

Totals 135 0.3375 0.1688 85 0.175

7.4 Powerhouse and Switchyard

The final site of a powerhouse and associated switchyard may be subject to change but for

purposes of this assessment it is taken from the November 2013 Scheme plans supplied by

Westpower as at or about NZTM E1415320; N5223700. This infrastructure involves a

proposed building area of 30 metres x 15 metres that will be permanently occupied, giving a

total potentially affected area of 450 m2, and an associated switchyard area of 20 metres x 30

metres, that will also require permanent clearance of the 600 m2

site it occupies. There is also

a requirement for an area surrounding the powerhouse and switchyard for vehicle and other

access that will be hard-fill (graveled and possibly surfaced e.g. sealed) and remain

permanently cleared after construction. This will be about twice the area occupied by the

powerhouse and switchyard nominal dimensions combined i.e., will involve an additional c.

2,100 m2 of vegetation clearance (see Appendix A, Map 3). While construction is likely to

involve temporary clearance of additional vegetation about the building sites for e.g.

foundation excavation and equipment/materials storage, area potentially affected by this is

included in and assumed to become part of the permanent hard-fill area. Area potentially

affected by these Scheme components is given in Table 12. Vegetation effects are considered

negligible.

Table 12: Powerhouse, Switchyard and Hard-fill Zone Potentially Affected Area Within

Vegetation Type.

Vegetation

Type

Construction

(ha)

Permanent

(ha)


Construction (ha)

2/2 Powerhouse 0.045 0.045 0.0

2/2 Switchyard 0.060 0.060 0.0

2/2 Hard-fill Zone 0.210 0.210 0.0

Totals 0.315 0.315 0.0

54

7.5 Powerhouse to Tunnel Portal Exit Access Road and Penstock

In addition to the access road to the powerhouse location there is also a requirement for a

short section of access road from the powerhouse to the tunnel portal exit. For purposes of

this assessment this road section is assumed to extend from the southern margin of the hard-

fill area surrounding the powerhouse, along the alignment of the penstock and immediately

adjacent to it. Based on November 2013 Scheme plans supplied by Westpower, distance

traversed is c. 85 metres and an assumed width is c. 15 metres to allow the short section of

penstock required from the tunnel portal exit to the powerhouse to be run adjacent to this road

and within the 15 metre strip (see Appendix A, Map 3). Vegetation effects are considered

negligible.

Table 13: Powerhouse to Tunnel Portal Exit Road and Penstock Distance and Potentially

Affected Areas Within Vegetation Type.

Vegetation

Type

Distance

(m)

Construction

(ha)

Permanent

(ha)


Construction (ha)

2/2 85 0.1275 0.1275 0.0

Totals 85 0.1275 0.1275 0.0

7.6 Tailrace

Indicative tailrace location is shown on Appendix A, Map 3. An estimated width affected by

the tailrace and its construction is 20 metres3 and total distance measured from Appendix A,

Map 3 is c. 120 metres, of which c. 100 metres is through ground that is vegetated or partially

so, the remainder being in the gravel/rock zone of the Waitaha River bed. Potentially affected

area carrying vegetation is therefore c. 2,000 m2, all of which is expected to be permanently

cleared/occupied. A settling pond for interception of sediment during tunnel excavation and

powerhouse construction is proposed. Its planned dimensions are 20 metres wide x 30 metres

long, to be constructed in the tailrace zone and later subsumed by the tailrace, so that it does

not add to the affected area. The tailrace crosses the true-right riparian margin of the Waitaha

River at an oblique angle, affecting an estimated 250 m2 of this riparian zone, approximately

half of which is vegetated or partially vegetated, the remainder being bare rock and gravel at

the point where the main channel of Alpha Creek exits the forest as of November 2013.

Potentially affected areas by vegetation type are shown in Table 14. The tailrace will involve

crossing the riparian margin of the Waitaha River true-right however the scale and type of

disturbance to vegetation for this alone is well within the scale of disturbance that could occur

naturally by e.g. bank-cutting, slips or tributary course changes, all common occurrences in

this environment and climate. Vegetation types present in riparian margins in this area are not

necessarily unique or distinguished floristically from their counterparts not occupying a

riparian strip. It is the arbitrary riparian width designation in the Proposed Regional Land and

Water Plan (WCRC, 2013) and Westland District Plan (WDC, 2002) of 10 metre distance

3 Pers. Comm: S. Matheson, Westpower/Electronet, telephone conversation with J. Derks, 7/9/2012.

55

from a waterway bank, not vegetation, that distinguishes these zones – vegetation present

would not preclude the activity. Vegetation effects are considered negligible.

Table 14: Tailrace Distance and Potentially Affected Area Within Vegetation Type.

Vegetation

Type

Distance

(m)

Construction

(ha)

Permanent

(ha)


Construction (ha)

2/2 100 0.200 0.200 Waitaha River true-right 0.025*

Totals 100 0.200 0.200 0.025*

Note: Tailrace riparian area potentially affected as marked * is an estimate based on an oblique angle crossing

of the Waitaha River true-right 10 metre riparian zone by the 20 metre wide tailrace – actual affected area may

vary depending on final angle of traverse of the tailrace through the riparian margin, however any variation in

affected area carrying vegetation is expected to be minimal.

7.7 Stopbank Protection for Powerhouse, Switchyard, Tailrace, Penstock and Access Road

There is potential flood risk to the site of powerhouse, switchyard, tailrace, penstock and

portion of access road located on the alluvial flat. The predominant component of risk is via a

channel that is vegetated, but that shows signs of occasional water flow from the main river at

times of heavy flooding, that runs along the eastern margin of the flat. There may also be a

risk if the course of the river were to deviate from its current position and cut on the true-right

side.

Stopbank rock protection is specified in construction planning, with indicative stopbank

location shown on Appendix A, Map 3. The affected area estimate is based on an armour-

rocked stopbank with 12 metre basal width, commencing at the toe of the terrace near the

southern extremity of the alluvial flat, extending across the upstream end of the flood channel

and along the western flat margin to link with the hard fill zone surrounding the powerhouse

and switchyard, and finish at its northern end, a distance of c. 195 metres. Some portion (estimated to be 25% of total width) of the foot of this structure is likely to

occupy the bed of the Waitaha River, this zone being deemed un-vegetated for affected area

calculation. The remainder is deemed to be located in the Waitaha River true-right riparian

margin. Under these assumptions, total area potentially affected is 2,340 m2, of which

1,755 m2 is at least partially vegetated riparian margin. Potentially affected areas by

vegetation type are shown in Table 15.

Vegetation types present in riparian margins in this area are not necessarily unique or

distinguished floristically from their counterparts not occupying a riparian strip. It is the

arbitrary riparian width designation in the Proposed Regional Land and Water Plan

(WCRC, 2013) and Westland District Plan (WDC, 2002) of 10 metre distance from a

waterway bank, not vegetation, that distinguishes these zones – vegetation present would not


Magnitude of effect of this activity on vegetation is within the scale of disturbance that could

occur naturally by e.g. bank-cutting, slips or river course changes, all common occurrences in

this environment and climate. It is likely that a portion of the stopbank will support a

vegetation cover, in particular the river side, if flood events deposit silt between the stopbank

56

rocks. A conservative estimate of area that could be revegetated by either natural regeneration

or supplementary planting (see Section 10.2) is 33% of the total affected in construction.

Effect on vegetation is likely negligible.

Table 15: Stopbank Distance and Potentially Affected Area Within Vegetation Type.

Vegetation

Type

Distance

(m)

Construction

(ha)

Permanent

(ha)

Placement Within

Riparian Margins:

Distance (m)

Placement Within Riparian

Margins:

Construction (ha)

2/2 195 0.1755 0.1169 True-right side of

Waitaha River

195

True-right side of Waitaha

River

195 m x 9 m strip = 0.1755

Totals 195 0.1755 0.1169 195 0.1755

8.0 Other Observations Relating to Vegetation – Area 2

Generally, the state of vegetation of all types described above, both within the areas of

proposed works and the wider area, appears healthy and stable with the exception of change

due to naturally caused events e.g. occasional slips, changes in river channel location, and

windfall zones, these being random and relatively infrequent. While possums and deer are

present, browse effect on indigenous vegetation at all sites appears very low. Sign indicates

low possum numbers. The sign that is present tends to be concentrated about forest margins

bordering river flats and on the recent terraces and stream side faces with predominant

broadleaved hardwood shrub cover, however the possum numbers present are having a very

limited effect on vegetation in the Scheme project footprint and surrounding area.

Likewise for deer, sign is sporadic and concentrated on the grassed and sandy areas of flats.

Grazing is evident on grassed clearing/flat areas, but appears occasional and at a low level –

this will be seasonally variable, highest in spring and summer – however even then would not

be of significant detriment to the majority of indigenous vegetation present given the low deer

population density. Once into areas of shrub/bush cover, deer movements disperse and

vegetation appears little affected.

No goats or goat sign were observed in this part of the Scheme area on the true-right of the

Waitaha River above Macgregor Creek, however goats are present in moderate numbers on

the true-left, from below Douglas Creek up to Labyrinth Creek.

Cattle grazing appears to have been regular on the alluvial flat zone bordering the true-right of

the Waitaha River and true left of Macgregor Creek that carries Vegetation Type 2/7, with

sign of heavy grazing having occurred a few weeks prior to 2012 field work in this area. It has

not affected vegetation other than the grasses and broadleaved species present in this zone and

cattle do not appear to traverse further upriver on the true-right side.

Exotic herbaceous weed species adapted for wind dispersal of seed (e.g. Cirsium spp.) are

present in low concentrations outside of forest areas e.g. along river and stream margins and

in admixture with grasses on more open alluvial flat areas. Scattered Ulex europaeus plants

have established in low density in a restricted area of the alluvial flat zone bordering the true-

57

right of the Waitaha River and true-left of Macgregor Creek that carries Vegetation Type 2/7.

No other brushweed species were noted in any areas.

9.0 Significance and Natural Values Assessment

The West Coast Conservation Management Strategy 2010 – 2020 (DOC, 2010), developed

under provisions of the Conservation Act, 1987: “establishes objectives for the integrated

management of natural and historic resources … and is the key conservation management

tool which the Department uses to implement legal, policy and strategic direction”

(DOC, 2010, p. 3). The West Coast Conservation Management Strategy 2010 – 2020 Part 3,

Section 3.3.2.3 Prioritising Natural Heritage Work, Policy 1 specifies seven criteria to apply

in identifying what might constitute natural heritage and assessing its relative value.

The West Coast Regional Policy Statement (2000) - Policy 9.2 prescribes sixteen

criteria/guidelines to be considered in recognising and providing protection for areas of

indigenous vegetation, any one of which may determine whether an area is significant for

purposes of Section 6(c) of the Resource Management Act 1991 (RMA, 1991). The Westland

District Plan, Section 4.9 Natural Habitats and Ecosystems - Policy D (WDC, 2002)

prescribes eight criteria for use in defining areas of significant indigenous vegetation and

significant habitats of indigenous fauna for purposes of Section 6(c) of the Resource

Management Act 1991 (RMA, 1991) and states that all areas of significant indigenous

vegetation and habitats shall meet one or more of these.

Table 16 contains the criteria from the three different sources discussed above and aligns

these criteria where they vary in terminology but are deemed to have the same or similar

intent, and where a criterion from one source can apply more than once to a criterion or

criteria from other sources.

In Table 16 and or purposes of discussion of significance and natural values assessment the

following abbreviations are assigned:

RPS = West Coast Regional Policy Statement (2000).

WDP = Westland District Plan (2002).

CMS = West Coast Conservation Management Strategy 2010 – 2020.

The structure of some criteria encompasses wider habitat considerations, applicable to flora as

a component of habitat and to any fauna reliant on that habitat. Habitat significance and

natural heritage values as they apply to fauna are covered in detail by other surveys and

reporting re the Scheme (refer Buckingham, 2014 and Whittaker, 2013).

An assessment of the vegetation in Area 1 and Area 2 is made against each of the criteria

groupings that apply via discussion under headings based on the criteria in Table 16 that are

relevant to terrestrial flora.

58

Table 16: Criteria Framework4 for Determining Significance and Natural Heritage Values for Purposes of Section 6(c) of the Resource Management Act 1991 (RPS & WDP)

and Natural Heritage Values (CMS).

RPS

(Policy 9.2)

WDP

(Policy 4.9D)

CMS

(Policy 3.3.2.3(1)) a) The desirability for their protection by statute or covenant.

b) Protection status, including reserves created under the West Coast

Accord.

(iv) Protected Status.

The area has been set aside by New Zealand Statue or Covenant for protection and

preservation or is a recognised wilderness area.

c) The degree to which the area is representative of an association of

species or an ecosystem that is typical of the region.

(ii) Representativeness.

The area is one of the best examples of an association of species which is typical

of its ecological district.

Representativeness,

Diversity.

d) The likelihood of the area retaining its viability, quality and integrity of

processes over a long time period.

(i) Intactness and Size.

The area is unmodified by human activity, comprises a predominantly intact

indigenous system and is not affected in a major way by weed or pest species;

AND,

The area of indigenous vegetation has a predominant cover of 5 hectares or more.

Viability,

Intactness.

e) The presence or absence of an indigenous species or community of

indigenous species that is rare or threatened regionally or nationally.

(vi) Threat.

The area supports an indigenous species or community of species which is

threatened within the ecological district or threatened nationally.

Threatened Species

and Habitat.

f) The degree to which the area is distinctive in terms of indigenous species

that are unusual, endemic, or that reach a distribution limit in the region.

(iii) Distinctiveness.

The area has indigenous species or an association of indigenous species which is

unusual or rare in the ecological district, or endemic or reaches a distribution limit

in the ecological district. The area may be distinctive because of the influences of

factors such as altitude, water table, soil type or geothermal activity.

Diversity.

g) The extent to which the area has been modified from a natural state or

affected by weeds or pest species.


The area is unmodified by human activity, comprises a predominantly intact

indigenous system and is not affected in a major way by weed or pest species;

AND,

The area of indigenous vegetation has a predominant cover of 5 hectares or more.

Viability,

Intactness.

4 Framework adapted from model provided by M. Kennedy, West Coast Planning Ltd., Paroa.

59

Table 16: Criteria Framework for Determining Significance and Natural Heritage Values for Purposes of Section 6(c) of the Resource Management Act 1991 (RPS & WDP)

and Natural Heritage Values (CMS) Ctd.

RPS

(Policy 9.2)

WDP

(Policy 4.9D)

CMS

(Policy 3.3.2.3(1)) h) Its connection with other areas of significant indigenous vegetation or

significant habitats of indigenous fauna.

(v) Connectivity.

The area is connected to one or more other significant areas in a way (including

through ecological processes) which makes a major contribution to the overall

value or natural functioning of those areas.

Viability.

i) Its contribution to the avoidance or mitigation of natural hazards.

j) Its use or value on a local, regional or national scale for public access,

recreation, amenity and heritage purposes.

(viii) Scientific or Other Cultural Value.

The area is a type, locality or other scientific reference area, is listed as a

geopreservation site, or has a distinctive amenity value (e.g. it contributes to a

distinctive and outstanding landscape of the district, has other significant cultural

value or is of international importance).

Natural Landscape

Character.

k) The relationship of Poutini Ngai Tahu and their culture and traditions

with their ancestral lands, water, sites, waahi tapu, mahinga kai and other

taonga.

(viii) Scientific or Other Cultural Value.

The area is a type, locality or other scientific reference area, is listed as a

geopreservation site, or has a distinctive amenity value (e.g. it contributes to a

distinctive and outstanding landscape of the district, has other significant cultural

value or is of international importance).

Taonga Species and

Habitat.

l) The contribution of the area or habitat to maintenance and enhancement

of ecological and reproductive processes, water quality, water flow and

soil conservation.

(v) Connectivity.

The area is connected to one or more other significant areas in a way (including

through ecological processes) which makes a major contribution to the overall

value or natural functioning of those areas.

Diversity.

m) The relationship of the area or habitat to any water body included in a

water conservation order.

n) Whether they occur near wetlands and estuaries.

o) The importance to migratory species, including whitebait. (vii) Migratory Species.

An inter-tidal area or area of forest, wetland, lake, estuary or other natural habitat

that is important for migratory species or for breeding, feeding or other vulnerable

stages of indigenous species.

Diversity,

Taonga Species and

Habitat.

p) The relevance of ecological districts in relation to matters (c), (e) and (f).

60

For comparison of vegetation type occurrence/distribution in considering significance and

natural heritage values and to provide context between areas potentially affected by the

Scheme compared to the areas in the locale and further afield, a GIS analysis5 using Land

Cover Database (LCDB)6 land cover classes aligned as far as practicable to their counterpart

vegetation types as described above for the Scheme area, has been done at three levels:

1. For the Wilberg Ecological District (Appendix A, Map 4).

2. For the Waitaha catchment being all that area within the catchment south of the

NZTM North 5226000 line so as to exclude lowland cover types and areas not

relevant for purposes of this comparison (Appendix A, Map 4).

3. For the Base Area as previously defined in Section 4.0 and as shown on Appendix A,

Map 5 and Appendix A, Map 6, considered the Scheme’s locale.

While the different LCDB land cover classes are mapped for individual areas down to one

hectare, the land cover class descriptions are necessarily broad, with 33 land cover/land use

classes covering all land cover and land use (including urban/infrastucture and agricultural)

activities across New Zealand. The detailed field survey undertaken as a basis of this report

and the differentiation and mapping of vegetation cover gives a much finer stratification. To

enable comparison by area, Vegetation Types described for Area 1 and Area 2 are, where

necessary, amalgamated to fit with the most applicable LCDB land cover type, with results

given in Table 17.

Total land area within the Wilberg Ecological District is c. 84,113.8 hectares and within the

Waitaha catchment (as previously defined) is c. 15,998.8 hectares. Of these total areas,

62,937 hectares = 75% of the Wilberg Ecological District and 12,041 hectares = 75% of the

Waitaha catchment, carry indigenous vegetation of some type under the LCDB land cover

classes (i.e., the above areas exclude exotic forest, deciduous hardwoods, high producing

exotic grassland, lakes and ponds, permanent ice and snow and river land cover classes).

GIS analysis undertaken using the LCDB land cover classes matched to the indigenous forest

type assemblages (all Vegetation Types excluding Vegetation Type 1/4) potentially affected

by the Scheme shows these are present:

Across 27,903 hectares comprising 44% of the Wilberg Ecological District indigenous

vegetation cover.

Across 4,334 hectares comprising 36% of the Waitaha catchment indigenous

vegetation cover.

They are therefore common and widely represented in both Wilberg Ecological District and

the Waitaha catchment. The indigenous forest assemblages also occur extensively in

catchments of similar valleys throughout central Westland (James et al., 1973; Wardle, 1979).

5 GIS mapping and GIS area data procurement services supplied by Boffa Miskell Ltd., Christchurch. Data

analysis and summarisation by TACCRA Ltd. 6 Ref: www.lcdb.scinfo.org.nz - Land Cover Database v.3.0, 2012.

61

Vegetation Type 1/4, a small area of which is also potentially affected by the Scheme, is

analogous to the LCDB Sub Alpine Shrubland cover class. Under those criteria, GIS analysis

shows it is present:

Across 17,269 hectares comprising 27% of the Wilberg Ecological District indigenous

vegetation cover.

Across 4,249 hectares comprising 35% of the Waitaha catchment indigenous

vegetation cover.

As for the indigenous forest vegetation, this shrubland vegetation is also common and widely

represented, not only in the areas noted above but in other valleys throughout central

Westland (James et al., 1973; Wardle, 1979).

62

Table 17: LCDB Land Cover Class and Analogous Vegetation Type Area Summaries and Comparisons for Wilberg Ecological District, Waitaha

Catchment and Base Area and the Scheme’s Project Footprint.

LCDB Land Cover Class +

Corresponding Vegetation Type(s)*

Area in

Wilberg

Ecological

District

Area in

Waitaha

Catchment

Area

In

Base

Area

Area of Scheme

Project

Footprint in

LCDB Cover

Class/Vegetation

Type(s)

Area in Base

Area as % of

LCDB Cover

Class/Vegetation

Type(s) in

Wilberg

Ecological

District

Area of Scheme

Project

Footprint as %

of LCDB Cover

Class/Vegetation

Type(s) in

Wilberg

Ecological

District

Area of Scheme

Project

Footprint as %

of LCDB Cover

Class/Vegetation

Type(s) in

Waitaha

Catchment

Area of Scheme

Project

Footprint as %

of LCDB Cover

Class/Vegetation

Type(s) in Base

Area

Alpine Grass/Herbfield 2,994.50 509.06 0.00 0.00 0.00 0.00 0.00 0.00 Broadleaved Indigenous Hardwoods

*(2/4, 2/4A, 2/5 & 2/6)

379.13 126.82 29.97 1.8675 7.90 0.493 1.50 6.36

Deciduous Hardwoods 0.00 1.20 0.00 0.00 0.00 0.00 0.00 0.00

Exotic Forest 4.34 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Fernland 0.29 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Forest - Harvested 22.41 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Gorse and/or Broom

*(2/9)

137.19 63.69 12.14 0.0720 8.85 0.052 0.11 0.59

Gravel and Rock

*(2/7)

14,913.98 3,254.76 21.21 0.00 0.14 0.00 0.00 0.00

High Producing Exotic Grassland 310.32 62.53 0.00 0.00 0.00 0.00 0.00 0.00

Indigenous Forest

*(1/1, 1/2, 1/3, 2/1, 2/2, 2/3, 2/3A, 2/3B & 2/8)

27,386.56 4,143.05 343.24 2.2880 1.25 0.008 0.06 0.67

Lake and Pond 29.31 44.51 0.00 0.00 0.00 0.00 0.00 0.00

Landslide 75.29 16.56 3.00 0.00 3.99 0.00 0.00 0.00

Low Producing Grassland 127.83 1.79 0.00 0.00 0.00 0.00 0.00 0.00

Manuka and/or Kanuka 3.86 0.57 0.00 0.00 0.00 0.00 0.00 0.00

Permanent Snow and Ice 5,574.60 537.68 0.00 0.00 0.00 0.00 0.00 0.00

River 343.92 55.42 15.78 0.00 4.59 0.00 0.00 0.00

Sub Alpine Shrubland

*(1/4)

17,268.94 4,249.10 10.84 0.2980 0.06 0.002 0.007 2.75

Tall Tussock Grassland 14,541.30 2932.10 0.00 0.00 0.00 0.00 0.00 0.00 Totals 84,113.79 15,998.84 436.19 4.5255 0.52 n.a. n.a. n.a.

Note: All area figures in the above table are hectares.

Note: the Waitaha catchment is not entirely contained within the Wilberg Ecological District (see Appendix A, Map 4) therefore it can exhibit individual LCDB land cover class areas greater

than those for the Wilberg Ecological District, e.g., Lake and Pond.

Note: Project Footprint as used in the above table refers to the area that encompasses temporary (i.e. construction) and permanent installations, infrastructure and accessways.

Note: * Denotes the Vegetation Types identified in this report e.g. 2/1, 2/2, 2/3 etc. as assigned to their respective or most representative LCDB land cover class as mapped under the LCDB. In

this case Vegetation Type 2/7 is shown as Gravel and Rock and Vegetation Type 2/9 is shown as Gorse and/or Broom under LCDB mapping whereas they would more aptly be classified

Broadleaved Indigenous Hardwood.

63

9.1 Area 1 and Area 2 Vegetation Type(s) – Significance and Natural Heritage Value Assessment

The criteria or criteria groups contained in Table 16 are used as the basis for discussion and

analysis in determining which, if any, result in terrestrial flora being considered significant

indigenous vegetation or of high natural heritage value, and if so, what effects of the Scheme

would be on it.

RPS 9.2(a). The desirability for their protection by statute or covenant.

Area 1 & Area 2 Vegetation Characteristics Compared to Criterion RPS 9.2(a):

The majority of the Scheme project area carrying indigenous flora is within the Waitaha

Conservation Area - already public conservation land. The remainder of the Scheme project

area i.e. north of Macgregor Creek, is predominantly freehold farmland with lesser amounts

of other Crown land and legal road. Indigenous terrestrial flora that is present on these areas

of other tenure is not considered to be of conservation or other protection (e.g. soil and water)

value warranting inclusion under any statute or covenant.

Significance Outcome: Not identified as significant indigenous vegetation.

RPS 9.2(b). Protection status, including reserves created under the West Coast Accord.

WDP 4.9D(iv) Protected status - The area has been set aside by New Zealand Statue or

Covenant for protection and preservation or is a recognised wilderness area.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(b) &

WDP 4.9D(iv):

The majority of the Scheme project area carrying indigenous flora is within the Waitaha

Forest conservation unit. As conservation land (stewardship land), the area is administered

under New Zealand statute. It is not part of a recognised wilderness area.

Significance Outcome: Significant indigenous vegetation.

Note: These criteria prescribe an arbitrary designation. They do not infer or confer high

vegetation values. The land area of Westland is approximately 1,140,000 hectares.

Approximately 85% (969,850 hectares) is administered by the Department of Conservation

(WDC, 2002), therefore the protected status characteristic is very common. The Scheme

would not affect status of land administration for the Waitaha Forest conservation unit and the

activity would not be precluded on the basis of vegetation present in the Scheme project

footprint.

64

RPS 9.2(c). The degree to which the area is representative of an association of species or an

ecosystem that is typical of the region.

WDP 4.9D(ii). Representativeness - The area is one of the best examples of an association of

species which is typical of its ecological district.

CMS 3.3.2.3(1). Representativeness and Diversity.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(c), WDP 4.9D(ii)

& CMS 3.3.2.3(1) – Representativeness and Diversity:

The predominant vegetation encompassed by Area 1 and Area 2 is typical of that observed on

streamsides, alluvial flats, terrace sequences and hill footslope and side-slope areas across a

relatively wide altitudinal range (e.g. 100 – 600 m.a.s.l.) within forested catchments. For

example, the Wilberg Ecological District (including the Waitaha, Wanganui, Poerua and

majority of the Perth catchments) contains in excess of 45,100 hectares of similar vegetation

cover. The Waitaha catchment contains in excess of 8,500 hectares. While typical, none of the

Vegetation Types in Area 1 and Area 2 would alone or together be distinguished as one of the

best examples of a species association noted as characteristic of the Wilberg Ecological

District, these being: mixed podocarp-hardwood forest on lower slopes; rata-kamahi forest at

higher altitudes; subalpine scrub; snow tussockland; cushion bogs; herbfield and high-alpine

vegetation (McEwen, 1987). Species present and their assemblages do not display degrees of

representativeness or diversity that distinguish these areas from counterparts in their location

in the Waitaha catchment, in the Wilberg Ecological District or the region.

Significance/Natural Heritage Value Outcome: Not identified as significant indigenous

vegetation or of high natural heritage value.

RPS 9.2(d). The likelihood of the area retaining its viability, quality and integrity of processes

over a long time period.

WDP 4.9D(ii). Intactness and Size - The area is unmodified by human activity, comprises a

predominantly intact indigenous system and is not affected in a major way by weed or pest

species; AND, The area of indigenous vegetation has a predominant cover of 5 hectares or

more.

CMS 3.3.2.3(1). Viability and Intactness.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(d), WDP 4.9D(ii)

& CMS 3.3.2.3(1) – Viability and Intactness:

Vegetation present in Area 1 and Area 2 is part of a predominantly intact indigenous system

greater than 5 hectares in cover and is not affected in a major way by weed or pest species. It

has not been modified to any marked extent by human activity.

Environmental and physical influences on vegetation in the Waitaha catchment are unlikely to

change in the long term. Effects of natural events (including catastrophic disturbance by e.g.

65

major earthquake) may alter current vegetation characteristics (including species mix,

frequency of occurrence, size class distributions, change from mature to regenerational phases

of forest cover) over time, however the area should retain viability, intactness and integrity of

processes.

Significance/Natural Heritage Value Outcome: Significant indigenous vegetation, based on

area and lack of modification. Areas exhibit high natural heritage value due to intactness and

viability retention potential.

Note: Effects of the Scheme on the area’s vegetation viability, quality, integrity and intactness

are likely to be inconsequential considering its small project footprint within the surrounding

contiguous area (total footprint of 4.5255 hectares within the indigenous vegetation cover of

the Base Area of c. 396 hectares, representing an affected area of 1.1%), combined with

measures to be implemented wherever practicable, that avoid affecting important habitat

components e.g. large forest trees.

RPS 9.2(e). The presence or absence of an indigenous species or community of species that is

rare or threatened regionally or nationally.

WDP 4.9D(vi). Threat - The area supports an indigenous species or community of species

which is threatened within the ecological district or threatened nationally.

CMS 3.3.2.3(1). Threatened Species and Habitat.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(e), WDP 4.9D(vi)

& CMS 3.3.2.3(1) – Threatened Species and Habitat:

No indigenous flora species have been identified (see Species List, Appendix B) that are

listed as threatened by de Lange, et al., (2012) or Hitchmough et al., (2007). This applies

nationally and to the Wilberg Ecological District.



66

RPS 9.2(f). The degree to which the area is distinctive in terms of indigenous species that are

unusual, endemic, or that reach a distribution limit in the region.

WDP 4.9D(iii). Distinctiveness - The area has indigenous species or an association of

indigenous species which is unusual or rare in the ecological district, or endemic or reaches

a distribution limit in the ecological district. The area may be distinctive because of the

influences of factors such as altitude, water table, soil type or geothermal activity.

CMS 3.3.2.3(1). Diversity.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(f), WDP 4.9D(iii)

& CMS 3.3.2.3(1) - Diversity:

Vegetation types and assemblages are widely represented in the Wilberg Ecological District

and in neighbouring ecological districts (refer discussion under RPS 9.2(c) and WDP 4.9D(ii)

above). No species observed reaches a distribution limit or is endemic here and physical

factors do not promote distinctiveness. Species diversity is no more or less varied for

vegetation types in these areas than in their counterparts in the general area (Base Area), other

parts of the Wilberg Ecological District or at similar sites in other valleys of central Westland

and would not differentiate Area 1 or Area 2 as having high natural heritage value.



RPS 9.2(g). The extent to which the area has been modified from a natural state or affected by

weeds or pest species.

WDP 4.9D(i). Intactness and Size - The area is unmodified by human activity, comprises a

predominantly intact indigenous system and is not affected in a major way by weed or pest

species; AND, The area of indigenous vegetation has a predominant cover of 5 hectares or

more.

CMS 3.3.2.3(1). Viability and Intactness.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(g), WDP 4.9D(i)

& CMS 3.3.2.3(1) Viability and Intactness:

Vegetation present in Area 1 and Area 2 is part of a predominantly intact indigenous system

greater than 5 hectares in cover and is not affected in a major way by weed or pest species. It

has not been modified to any marked extent by human activity.

While deer and possums are present in the areas, their observed effect on vegetation is low at

current population levels. Brushweed establishment (Ulex europaeus) appears restricted to a

minor pocket at the northern extremity of Area 2 and other weed establishment is limited to

non-forested areas, involving herbaceous species adapted to wind dispersal of seed. The

majority of vegetation cover is closed-canopy indigenous forest or shrubland that will

generally limit the establishment of Ulex europaeus and herbaceous weeds (e.g. Cirsium spp.)

The area should retain viability and intactness.

67

Significance/Natural Heritage Value Outcome: Significant indigenous vegetation, based on

area and lack of modification. Areas exhibit high natural heritage value due to intactness and

viability retention potential.

RPS 9.2(h). Its connection with other areas of significant indigenous vegetation or significant

habitats of indigenous fauna.

WDP 4.9D(v). Connectivity - The area is connected to one or more other significant areas in

a way (including through ecological processes) which makes a major contribution to the

overall value or functioning of those areas.

CMS 3.3.2.3(1). Viability.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(h), WDP 4.9D(v)

& CMS 3.3.2.3(1) - Viability:

Vegetation cover of Area 1 and Area 2 is contiguous with the extensive area of similar types

that form a continuous unbroken sequence both north-west from the Waitaha River to higher

altitude forest of the eastern side of the Hitchen Range, and from north to south on the true-

right side of the Waitaha River from the lower to upper valley. It is therefore connected to,

and is a component of, habitat of other significant areas however the amount contained in the

Scheme’s project footprint is extremely small (1.1% of Base Area vegetation) and would not

make a major contribution to the overall value or functioning of those other areas or detract

from their viability if modified.



RPS 9.2(i). Its contribution to the avoidance or mitigation of natural hazards.

Area 1 & Area 2 Vegetation Characteristics Compared to Criterion RPS 9.2(i):

Retention of vegetation cover on steep terrain, in particular where high rainfall occurs, can

reduce risk of erosion and slips. Relative to the area of the Waitaha catchment, the areas of

vegetative cover within Area 1 and Area 2 contained in the Scheme’s project footprint would

be inconsequential as a contributor to the avoidance of natural hazards given the extremely

small area (4.5255 ha in total) involved and being primarily located on low altitude alluvial

flats and terrace landforms.


68

RPS 9.2(j). Its use or value on a local, regional or national scale for public access,

recreation, amenity and heritage purposes.

WDP 4.9D(viii). Scientific or Other Cultural Value - The area is a type, locality or other

scientific reference area, is listed as a geopreservation site, or has a distinctive amenity value

(e.g. it contributes to a distinctive and outstanding landscape of the district, has other

significant cultural value or is of international importance).

CMS 3.3.2.3(1). Natural Landscape Character.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(j), WDP 4.9(viii)

& CMS 3.3.2.3(1) - Natural Landscape Character:

None of the attributes of vegetation in Area 1 or Area 2 potentially affected by Scheme

components, within the project footprint, contribute to a type, locality or amenity which is

distinctive within the district in terms of vegetation composition or uniqueness.

No characteristic(s) distinguish vegetation in Area 1 or Area 2 from similar assemblages

present over a similar range of altitude and landforms in other parts of the Waitaha Valley and

neighbouring valleys. For example, the Wilberg Ecological District (including the Waitaha,

Wanganui, Poerua and majority of the Perth catchments) contains in excess of

45,100 hectares of similar vegetation cover. The Waitaha catchment contains in excess of

8,500 hectares. The range of types are also represented in valleys further north

(Hokitika/Whitcombe) and south (Whataroa, Franz Josef, Fox, Cook, Copeland/Karangarua)

in central and south Westland. Therefore, and as discussed above in terms of criterion

WDP 4.9D(viii), vegetation present in Area 1 and Area 2 would not be considered an

outstanding area of indigenous vegetation in terms of the criterion of distinctiveness. As a

result, and when viewed from the perspective of vegetation composition, the characteristics of

vegetation within Area 1 and Area 2 would not be a determining factor in identifying any

distinctive amenity and/or outstanding landscape character within the District. Assessment of

other components of natural landscape character are beyond the scope of this report and are

covered by other Scheme reporting (refer Boffa Miskell Ltd., 2014).

No parts of Area 1 or Area 2 containing the Scheme project footprint as it affects terrestrial

vegetation are listed geopreservation sites or scientific reference areas, have other significant

cultural value (as far as is known)7 or are of international importance.



7 Pers. Comm: S. Cotton, Consultation Officer, Westpower Ltd., 17/12/2013 - That cultural impact assessment

will be undertaken once a draft Assessment of Environmental Effects has been provided to iwi. Westpower has

met with Te Rūnanga o Ngati Waewae and Te Rūnanga o Makaawhio to discuss the proposal. While there have

been no significant concerns or issues raised to date re indigenous vegetation, there is a strong affiliation and

interest in preservation of natural values within the area such as the Whio/Blue Duck population.

69

RPS 9.2(k). The relationship of Poutini Ngai Tahu and their culture and traditions with their

ancestral lands, water sites, waahi tapu, mahinga kai and other taonga.

WDP 4.9D(viii). Scientific or Other Cultural Value - The area is a type, locality or other

scientific reference area, is listed as a geopreservation site, or has a distinctive amenity value

(e.g. it contributes to a distinctive and outstanding landscape of the district, has other

significant cultural value or is of international importance).

CMS 3.3.2.3(1). Taonga Species and Habitat.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(k), WDP

4.9D(viii) & CMS 3.3.2.3(1) – Taonga Species and Habitat:

Species of flora observed in Area 1 and Area 2 are common and widely represented in the

locale, in the wider Waitaha catchment and at similar sites in other valleys of central

Westland. As far as is known, vegetation within the Scheme’s project footprint area is not

recognised as having significant cultural value and the areas are not distinguished as

significant sites in respect of taonga species or their habitat in terms of vegetation8.



8 Pers. Comm: Op cit

5

70

RPS 9.2(l). The contribution of the area or habitat to maintenance and enhancement of

ecological and reproductive processes, water quality, water flow and soil conservation.

WDP 4.9D(viii). Connectivity - The area is connected to one or more other significant areas

in a way (including through ecological processes) which makes a major contribution to the

overall value or functioning of those areas.

CMS 3.3.2.3(1). Diversity.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(l), WDP 4.9D(viii)

& CMS 3.3.2.3(1) - Diversity:

Vegetation cover of Area 1 and Area 2 is contiguous with the extensive area of similar types

that form a continuous unbroken sequence both north-west from the Waitaha River to higher

altitude forest of the eastern side of the Hitchen Range, and from north to south on the true-

right side of the Waitaha River from the lower to upper valley. It is therefore connected to,

and is a component of, habitat of other significant areas however the amount contained in the

Scheme project footprint is extremely small (1.1% of the Base Area indigenous vegetation

cover) and would not make a major contribution to the overall ecological value or functioning

of those other areas. Natural breaks in vegetation connectivity via natural features e.g. the

Waitaha River bed, are of greater width and length than the narrow linear area footprint of the

access road/transmission line which constitutes the largest individual infrastructure item of

the Scheme. Any effect of the Scheme on water quality, water flow and soil conservation and

diversity via vegetation change would be inconsequential considering the area involved.



RPS 9.2(m). The relationship of the area or habitat to any water body included in a water

conservation order.

Area 1 & Area 2 Vegetation Characteristics Compared to Criterion RPS 9.2(m):

The Waitaha River is not subject to a water conservation order. The nearest area subject to a

water conservation order is in excess of 100 km from the Scheme project area, being the

Ahaura River (National Water Conservation (Grey River) Order 1991 (WCRC, 2013)).


71

RPS 9.2(n). Whether they occur near wetlands or estuaries.

Area 1 & Area 2 Vegetation Characteristics Compared to Criterion RPS 9.2(n):

There are no areas of wetland vegetation in the Scheme project area, or recognised wetland

areas near it. The closest wetland listed (identifier HARP021 Lake Ianthe) in the Proposed

Regional Land and Water Plan (WCRC, 2013) is located at the southern end of Lake Ianthe.

The closest point of this wetland and Area 2 (Area 1 being further removed) is c. 9.1 km. It is

separated from the Scheme project area by the Bonar Range. No significance would apply to

vegetation in Area 1 or Area 2 under this criterion.


RPS 9.2(o). The importance to migratory species, including whitebait.

WDP 4.9D(vii). Migratory Species – An inter-tidal area or area of forest, wetland, lake,

estuary or other natural habitat that is important for migratory species for breeding, feeding

or other vulnerable stages of indigenous species.

CMS 3.3.2.3(1). Diversity, Taonga Species and Habitat.

Area 1 & Area 2 Vegetation Characteristics Compared to Criteria RPS 9.2(o), WDP 4.9D(vii)

& CMS 3.3.2.1(1) – Diversity, Taonga Species and Habitat:

While migratory fauna species may be present e.g. Long-tailed cuckoo in summer as an

international migrant and wood pigeon throughout the year as a locally-seasonal migrant

(Buckingham, 2014) in habitat afforded by the flora present, neither Area 1 nor Area 2

vegetation would constitute important habitat for migratory species, given the small areas

they contain and the widespread occurrence of the assemblages in other areas in the Waitaha

catchment and other central Westland valleys. The same assessment applies re natural values

and as noted by Buckingham (2014), the Scheme is expected to have little influence on

migratory species.



72

RPS 9.2(p). The relevance of ecological districts in relation to matters (c), (e) and (f).

Area 1 & Area 2 Vegetation Characteristics Compared to Criterion RPS 9.2(p):

Relevance of ecological districts is encapsulated in the criteria prescribed in the Westland

District Plan, Policy 4.9D (WDC, 2002) that specifically refer to ecological district

consideration and align with RPS 9.2(c) = WDP 4.9D - Representativeness, RPS 9.2(e) =

WDP 4.9D - Threat and RPS 9.2(f) = WDP 4.9D - Distinctiveness.

The discussion and assessment outcomes given above for those criteria also apply for this

criterion. For all three the result is:



9.2 Summary of Vegetation Significance and Natural Heritage Value

None of the seven criteria/guidelines set out in the West Coast Conservation Management

Strategy 2010 – 2020 Part 3, Section 3.3.2.3 Prioritising Natural Heritage Work, Policy 1,

(DOC, 2010) applied to assessment of vegetation in Area 1 or Area 2 result in high natural

heritage value status determination where there is no correspondence/alignment of a criterion

from Policy 4.9D of the Westland District Plan (WDC, 2002).

The same applies to significant indigenous vegetation status determination using the sixteen

criteria in the West Coast Regional Policy Statement (2000) - Policy 9.2 (WCRC, 2000)

where a significant indigenous vegetation outcome is not also concomitant with

correspondence/alignment of a criterion in Policy 4.9D of the Westland District Plan

(WDC, 2002).

Therefore, a summary as to whether any high natural heritage values pertain and of

significance of indigenous vegetation is provided by an outcome of significance under one or

more of the Westland District Plan (WDC, 2002) Policy 4.9D criteria (i.e., the WDP 4.9D

criteria discussed in Section 9.1). This alignment and summary is shown in Table 18.

73

Table 18: Summary of Significant Indigenous Vegetation and High Natural Heritage Value

Assessment Criteria Applicable To Area 1 and Area 2 Vegetation.

RPS

(Policy 9.2)

WDP

(Policy 4.9D)

CMS

(Policy 3.3.2.3(1)) b) Protection status, including reserves

created under the West Coast

Accord;

(iv) Protected Status.

The area has been set aside by New Zealand

Statue or Covenant for protection and

preservation or is a recognised wilderness area.

d) The likelihood of the area retaining its

viability, quality and integrity of

processes over a long time period;


The area is unmodified by human activity,

comprises a predominantly intact indigenous

system and is not affected in a major way by

weed or pest species; AND, The area of

indigenous vegetation has a predominant cover

of 5 hectares or more.

Viability,

Intactness.

f) The extent to which the area has been

modified from a natural state or

affected by weeds or pest species;


The area is unmodified by human activity,

comprises a predominantly intact indigenous

system and is not affected in a major way by

weed or pest species; AND, The area of

indigenous vegetation has a predominant cover

of 5 hectares or more.

Viability,

Intactness.

Vegetation of Area 1 and Area 2 (being contiguous with a greater area within the Waitaha

catchment) is significant indigenous vegetation under the Westland District Plan

(WDC, 2002) on the basis of two WDP (Policy 4.9D) criteria - intactness and size of area and

protected status. As shown in Table 16 and Table 18, the WDP (Policy 4.9D) criterion of

intactness and size also encompasses West Coast Regional Policy Statement (2000) - Policy

9.2 criteria d) and f) parameters re area retaining viability, quality and integrity of processes,

and extent of modification. The arbitrary designation as per the WDP (Policy 4.9D) protected

status criterion also encompasses West Coast Regional Policy Statement (2000) - Policy 9.2

criterion b). Both pertain to land administration and do not infer or confer high vegetation

values.

High natural heritage values of viability and intactness also pertain as per the West Coast

Conservation Management Strategy 2010 – 2020 (DOC, 2010) and are concomitant with the

WDP (Policy 4.9D) criterion of intactness and size.

Work undertaken by Westpower:

1. Contributes to a record of vegetation in this area at a more detailed level of

stratification and accuracy of description than available via the LCDB land cover type

stratification. Examples are Vegetation Type 2/7 being mixed scattered indigenous

hardwood shrub cover and grassed alluvial flat mapped as Gravel and Rock in the

LCDB system, and Vegetation Type 2/9, being indigenous streamside vegetation,

mapped under the LCDB system as Gorse and/or Broom.

74

2. Adds detail to vegetation records for the Wilberg Ecological District, where the

summary in McEwen (1987, p. 3) states:

“Vegetation: a sequence of vegetation belts characteristic of high rainfall areas where

beech is lacking: mixed podocarp-hardwood forest on lower slopes; rata-kamahi

forest at higher altitudes; subalpine scrub; snow tussockland, cushion bogs, herbfield

and high-alpine vegetation. Little botanical knowledge.”

These advances are consistent with management objectives and policies of the West Coast

Conservation Management Strategy 2010 – 2020, Section 3.3.2.1: Knowledge and

Information Needs, Objective 1, Policies 3 and 4 and under Section 3.3.2.1: Knowledge and

Information Needs rationale where it is acknowledged that extra information: “…may assist

with the management of conservation values.” (DOC, 2010, p. 73).

The criteria under which significance and high heritage values accrue to Area 1 and Area 2

vegetation are predominantly arbitrary (land status, size of area). Nothing was identified in

the field survey that suggests any vegetation community uniqueness, attributes or species

presence that would distinguish Area 1 and Area 2 vegetation from any other similar sites

throughout the central Westland area and that would preclude these areas in total or in part

from the proposed Scheme activities on the basis of vegetation. Reasons are:

No threatened flora species were identified and none are endemic to the areas.

All species recorded have a wide distribution range in the Waitaha catchment, the

Wilberg Ecological District and other neighbouring Ecological Districts e.g.

Whitcombe Ecological District to the north and Glaciers Ecological District to the

south.

The Scheme’s design that aims to minimise affected area by utilising tunnel access to

headworks infrastructure, aligning transmission line route and access road to reduce

clearance area and locating these wherever practicable on landforms that require least

earthworks and where mature podocarp/hardwood forest is least prevalent.

The project footprint of the Scheme is a very small component of its locale (1.1% of

the Base Area), and the operational footprint (area permanently cleared of vegetation)

is still less at 0.93% of the Base Area. Clearance of these amounts of vegetation of the

types involved would have inconsequential effect on vegetation connectivity,

intactness, or viability as high natural heritage values.

The Scheme would not affect status of land administration for the Waitaha Forest

Conservation Unit and the activity would not be precluded on the basis of vegetation

present in the Scheme’s project footprint area because its protected status designation

is arbitrary, not a consequence of vegetation.

75

10.0 Recommended Monitoring, Mitigation and Remediation

The Scheme’s overall effect on indigenous vegetation is considered minor. Design minimises

effects of infrastructure placement and permanently occupied area and effects associated with

construction, on vegetation. There are two potential effects on flora other than the areas

involved. These are the number of large trees that may be affected, and weed incursion risk.

Recommended measures aimed at reducing these effects or risk at sites of Scheme

activities/infrastructure follow.

10.1 Area 1 - Monitoring/Mitigation/Remediation:

All Places in Area 1 Where Earthmoving Machinery Enters:

Machinery should be thoroughly washed down (track-gear, undercarriage) prior to entering

any part of Area 1 so as to reduce risk of weed seed transport.

Tunnel Portal Entrance and Intake Access Road:

While no uniqueness in terms of overall vegetation type(s) is attributable to the general area

in which the possible road to the contractors’ facilities area is proposed, defining a route that

results in least damage to all vegetation, and especially large (60+ cm dbh) hardwood trees

and podocarp trees (30+ cm dbh) will be a priority. The tunnel portal entrance and intake

access road route and area descriptions contained in this report are indicative for purpose of

this assessment of effects and are based on the November 2013 Scheme plans provided by

Westpower. They may be subject to variation depending on final route location and

construction requirements that can only be determined after final line marking and survey is

complete. A component of this work would be to enumerate and mark any large trees in a

zone around the possible tunnel portal entrance site and within a fixed width of the road

formation centerline and use these data to make portal placement and road alignment

adjustments, subject to engineering considerations, to avoid such trees if possible.

Post-construction weed monitoring and control will be important, particularly where gravel is

carted in as this is a likely source of Ulex europaeus seed, and possibly other weeds e.g.

Leycesteria formosa. At least annual monitoring is recommended, and this should be on an

ongoing basis, with any necessary weed control undertaken as soon as practicable in the most

effective season for best control results for the species concerned, but in any case prior to

plants attaining seeding maturity.

Access Road To Contractors’ Facilities Area:

The same consideration to large tree avoidance applies here as to the intake access road.

This section of road will not be required after completion of headworks construction. Post-

construction and site decommissioning, weed monitoring and control will be important,

particularly where gravel is carted in as this is a likely source of Ulex europaeus seed, and

possibly other weeds e.g. Leycesteria formosa. At least annual monitoring during road use

and for a minimum of five seasons after decommissioning is recommended, with any

76

necessary weed control undertaken as soon as practicable in the most effective season for best

control results for the species concerned, but in any case prior to plants attaining seeding

maturity.

It is expected that natural regeneration of indigenous cover would occur relatively quickly if

scarification/ripping of compacted surfaces was undertaken and that it would comprise a

range of species present prior to works.

Contractors’ Facilities Area:

This facilities area will not be required post-construction of the headworks infrastructure and

the area can be rehabilitated via supplementary planting or left to regenerate naturally. It is

expected that natural regeneration would comprise a range of indigenous species present prior

to works, and occur relatively quickly if scarification/ripping of compacted surfaces to

provide fresh, loose gravel substrate was undertaken.

Post-construction and site decommissioning, weed monitoring and control will be important,

particularly where gravel is carted in as this is a likely source of Ulex europaeus seed, and

possibly other weeds e.g. Leycesteria formosa. The same monitoring and any necessary

control measures should be undertaken here as recommended above for the contractors’

facilities access road.

10.2 Area 2 - Monitoring/Mitigation/Remediation:

All Places in Area 2 Where Earthmoving Machinery Enters:

Machinery should be thoroughly washed down (track-gear, undercarriage) prior to entering

any part of Area 2 so as to reduce risk of weed seed transport.

Access Road/Transmission Line:

While no uniqueness in terms of overall vegetation type(s) is attributable to the general area

in which the possible access road and transmission line is proposed, defining a route that

results in least damage to all vegetation, and especially large (60+ cm dbh) hardwood trees

and podocarp trees (30+ cm dbh) will be a priority. Field observations indicate trees of these

sizes are in very low densities in all vegetation types likely to be affected by access road and

transmission line construction.

The access road/transmission line route and area descriptions contained in this report are

indicative for purpose of this assessment of effects and are based on the November 2013

Scheme plans provided by Westpower. They may be subject to variation depending on final

route location and construction requirements that can only be determined after final line

marking and survey is complete. A component of this work would be to enumerate and mark

all large trees within a fixed width of the road formation centerline and use these data to make

any practicable road alignment adjustments to avoid as many of these large trees as possible.

Relatively easy terrain of the landforms where this infrastructure construction is likely should

allow some route variation if required. Tree avoidance should be achievable, so that effect on

77

large forest trees is not considered a factor that would preclude any parts of the general area

from the activity.

Gravel carted in is a likely source of Ulex europaeus seed, and possibly other weeds e.g.

Leycesteria formosa. Continuing vehicle use to access the various facilities during the

operation of the Scheme poses a lesser risk of weed conveyance. Ongoing post-construction

weed monitoring and control will be important and should be a scheduled component of

Scheme maintenance.

Tunnel Portal Exit, Powerhouse, Switchyard, Hard-fill Area, Powerhouse to Tunnel Portal

Exit Access Road, Tailrace and Stopbank:

Natural regeneration of the range of species present prior to any clearance would be expected

to occur relatively quickly on any of the above areas not permanently occupied, e.g. the site of

the former Amethyst Power Scheme pipeline and access, exhibiting similar landform and

vegetation types, had become overgrown by indigenous vegetation within c. 10 years of

cessation of use. Supplementary planting could enhance speed of re-vegetation if required and

where suitable substrate exists. To increase speed and success of plant establishment in

rocked areas such as the stopbank, or the naturally rocky bed of the flood channel, deposition

of soil material (obtained from other Scheme component construction) over the armour-

rocked bank face(s) or flood channel bed, would be highly beneficial in any case and in

particular prior to any supplementary planting.

Gravel and rock carted in, and vehicle use present the same risks at these infrastructure sites

as for the access road/transmission line and the same provisions are applicable for all areas of

these facilities not covered by buildings or hard surface (e.g. concrete/seal) re weed

monitoring and any control.

11.0 Summary/Conclusions

11.1 Area 1 - Headworks and Associated Structures

Vegetation within Area 1 is significant indigenous vegetation under provisions of the

Westland District Plan (WDC, 2002) on the basis of two criteria - intactness and size

of area, and protected status. It would also be considered as having high natural

heritage values under West Coast Conservation Management Strategy 2010 – 2020

(DOC, 2010) criteria of intactness and viability.

The predominant vegetation types present at the site of proposed headworks and their

associated facilities are typical of streamside and side-slope areas across a relatively

wide altitudinal range (e.g. 100 – 500 m.a.s.l.) within forested Westland catchments.

They form a common assemblage widely represented in the rest of the Waitaha Valley

and in similar valleys throughout central Westland. Nothing was identified in the field

survey that suggests any vegetation community uniqueness, attributes or species

presence that would distinguish this site from any other similar sites throughout the

central Westland area and that would preclude any parts of it from the proposed

activity on the basis of its vegetation.

78

Areas given as construction, permanent and riparian (construction) in the following

summary table are not additive. The construction area is the expected maximum area

potentially affected by each Scheme component and the construction total is an

indication of the Scheme’s project footprint as it pertains to vegetation effect. Areas

given as permanent and riparian areas are sub-areas for purposes of describing amount

of vegetation clearance associated with a given Scheme component. In the case of

permanent areas these indicate the operational footprint of each Scheme component

and for the Scheme in total. Riparian areas are given because activities affecting

indigenous vegetation in riparian margins will require consideration for regional and

district planning provision purposes. The different areas of vegetation potentially

affected by each infrastructure component and in total are:

Area 1: Headworks and Associated Infrastructure

Item(s)

Construction

(ha)

Permanent

(ha)

Riparian

(Construction, ha)

Weir. 0.0050 0.0010 0.0

Intake Channel. 0.0325 0.0163 0.0

Intake Structure and Intake Portal. 0.0478 0.0278 0.0294

Tunnel Portal Entrance. 0.0187 0.0187 0.0

Tunnel Portal Entrance Apron, Intake Access Road

and River Protection at Road Toe.

0.1370 0.0790 0.0410

Road to Contractors’ Facilities Area. 0.1040 0.0 0.0300

Contractor’s Facilities Area. 0.2200 0.0 0.0

Flushing Tunnel Outlet. 0.0100 0.0100 0.0100

Totals 0.5750 0.1528 0.1104

Totals Rounded Up 0.58 0.16 0.12

Note: Areas given as rounded sub-totals and totals in the above table are rounded up to two decimal

places in every case so as to avoid dropping any area as could occur if using conventional rounding of

figures less than five. All areas are indicative based on November 2013 Scheme plans supplied by

Westpower and may vary from those given above depending on final design, survey and siting.

Note: Riparian areas are for streams >3metres wide where provisions of the Proposed Regional Land

and Water Plan (WCRC, 2013) and the Westland District Plan (WDC, 2002) prescribe 10 metre

riparian margin widths.

For headworks components and associated infrastructure, the scale of proposed works

is well within the spatial scale of natural disturbances typical of this environment i.e.

does not represent clearance of large areas in conjunction with a change in land use

and cover type. The nature of vegetation disturbance (removal) caused by the

proposed work would not be deemed inconsistent with natural disturbance events e.g.

slips, at this or similar sites. Construction involves clearance or at least some

disturbance to 0.58 hectares or 0.15% of the c. 396 hectares of the similar indigenous

forest vegetation/shrubland assemblages contained in the Base Area (being the zone

contiguous with Scheme activities, containing and surrounding this part of the Scheme

project footprint in terms of vegetation effects and considered its locale), 0.007% of

the 8,583 hectares of their counterparts in the Waitaha catchment and 0.001% of the

45,172 hectares of their counterparts in the Wilberg Ecological District, based on

LCDB land cover class data. The area permanently affected (operational footprint) is

significantly less, being 27% of the project footprint for headworks. Therefore, the

proposed activity is not considered to have any significant, long-term detrimental

effect on vegetation surrounding the proposed site and other than in the construction

phase, is a benign activity that would not affect the wider area in any way. Natural

regeneration should occur across any areas affected by construction (except those

areas occupied by structural components).

79

Access road construction from the tunnel portal entrance to the intake and to the

contractors’ facilities area accounts for the majority of area in taller forest cover

potentially affected by the Scheme in Area 1. While no uniqueness in terms of overall

vegetation type(s) is attributable to the general area in which the proposed access

roading is located, defining routes, subject to engineering considerations, that result in

least damage to all vegetation, and especially large (60+ cm dbh) hardwood trees will

be a priority.

The tunnel portal entrance site location will be primarily determined by engineering

considerations. While the potentially affected area is small, there may be large trees at

the site or in close proximity. If there is flexibility in shifting location, priority should

be given where possible to avoiding clearance of or damage to large podocarp

(30+ cm dbh) and large hardwood (60+ cm dbh) trees.

Vegetation types present in riparian margins in this area are not unique or

distinguished floristically from their counterparts not occupying a riparian strip. It is

the arbitrary riparian designation of fixed-width distance from stream bank, not

vegetation, that distinguishes these zones and that may have environmental planning

restrictions that would not otherwise apply. For streams 1 – 3 metres wide provisions

of the Proposed Regional Land and Water Plan (WCRC, 2013) prescribe 10 metre

wide riparian margins if dominant slope angle is >12o and 5 metre wide riparian

margins otherwise. This requirement will add some (expected to be relatively minor)

area to available estimates of affected riparian area, however the detailed field survey

and mapping of small stream location was not a component of work undertaken as the

basis of this report. The number and exact location of streams 1 - 3 metres wide that

are potentially affected will need to be determined for regional planning provision

purposes, although it is not considered that potential effects on vegetation will be any

greater than already assessed and considered.

Effects of the Scheme on the Area 1 vegetation (being classed as significant

indigenous vegetation under the Westland District Plan (WDC, 2002) criteria of

intactness and size of area, and protected status) and any contribution to high natural

heritage values under the West Coast Conservation Management Strategy 2010 – 2020

(DOC, 2010) criteria of intactness and viability are likely to be negligible. This

conclusion is based on:

o the very small amount of clearance that will occur within the surrounding

contiguous area (total headworks project footprint of 0.58 hectares within the

similar indigenous forest vegetation (385 hectares)/sub alpine shrubland

(11 hectares) assemblages of the Base Area); and,

o the temporary nature of the majority of clearance, with 0.16 hectares being the

Scheme’s operational footprint, combined with measures to be implemented

wherever practicable that avoid affecting important habitat components e.g.

large forest trees.

80

11.2 Area 2 - Tunnel Portal Exit, Access Road/Transmission Line, Stream Training, Powerhouse, Switchyard, Penstock, Tailrace and Stopbank Facilities

Vegetation within Area 2 is significant indigenous vegetation under provisions of the

Westland District Plan (WDC, 2002) on the basis of two criteria - intactness and size

of area, and protected status. It would also be considered as having high natural

heritage values under West Coast Conservation Management Strategy 2010 – 2020

(DOC, 2010) criteria of intactness and viability.

The vegetation types present on the recent alluvial flat and terrace sequence on which

the activities are proposed are typical of forested Westland catchments, being common

and widely represented in the Waitaha Valley, and in similar valleys throughout

central Westland. Nothing was identified in the field survey that suggests any

vegetation community uniqueness, attributes or species presence that would

distinguish this from any other similar areas or that would preclude any part of it from

the proposed activities on the basis of its vegetation.

Areas given as construction, permanent and riparian (construction) in the following

summary table are not additive. The construction area is the expected maximum area

potentially affected by each Scheme component and the construction total is an

indication of the Scheme’s project footprint as it pertains to vegetation effect. Areas

given as permanent and riparian areas are sub-areas for purposes of describing amount

of vegetation clearance associated with a given Scheme component. In the case of

permanent areas these indicate the operational footprint of each Scheme component

and for the Scheme in total. Riparian areas are given because activities affecting

indigenous vegetation in riparian margins will require consideration for regional and

district planning provision purposes. The different areas of vegetation potentially

affected by each infrastructure component and in total are:

Area 2: Infrastructure Item(s) Construction

(ha)

Permanent

(ha)

Riparian

(Construction, ha)

Tunnel Portal Exit and Construction Apron. 0.2480 0.1800 0.0

Access Road and Transmission Line 2.5470 2.4198 0.0450

Waterway Training and Flood Protection at Alpha

Creek.

0.3375 0.1688 0.1750

Powerhouse, Switchyard and Hard-fill Area. 0.3150 0.3150 0.0

Powerhouse to Tunnel Portal Exit Access Road and

Penstock.

0.1275 0.1275 0.0

Tailrace. 0.2000 0.2000 0.0250*

Stopbank as River Protection for Powerhouse,

Switchyard, Tailrace, Penstock and Access Road.

0.1755 0.1169 0.1755

Totals 3.9505 3.5280 0.4205

Totals Rounded Up 3.96 3.53 0.43

Note: Areas given as rounded totals in the above table are rounded up to two decimal places in every

case so as to avoid dropping any area as could occur if using conventional rounding of figures less

than five. All areas are indicative based on November 2013 Scheme plans supplied by Westpower and

may vary from those given above depending on final design, survey and siting.

Note: Riparian areas are for streams >3metres wide where provisions of the Proposed Regional Land

and Water Plan (WCRC, 2013) and the Westland District Plan (WDC, 2002) prescribe 10 metre

riparian margin widths. Tailrace riparian area potentially affected as marked * is an estimate based on

an oblique angle crossing of the Waitaha River true-right 10 metre riparian zone by the 20 metre wide

tailrace – actual affected area may vary depending on final angle of traverse of the tailrace through the

riparian margin, however any variation in affected area carrying vegetation is expected to be minimal.

81

For components of Scheme infrastructure in Area 2, the scale of proposed works does

not represent clearance of large areas in conjunction with a change in land use and

cover type. Construction (the project footprint) involves clearance or at least some

disturbance to 3.96 hectares or 1.0% of the c. 385 hectares of the similar indigenous

forest vegetation assemblages contained in the Base Area, (being the zone contiguous

with Scheme activities, containing and surrounding this part of the Scheme project

footprint in terms of vegetation effects and considered its locale), 0.09% of the 4,344

hectares of their counterparts in the Waitaha catchment and 0.01% of the 27,903

hectares of their counterparts in the Wilberg Ecological District, based on LCDB land

cover class data. The area permanently affected (operational footprint of 3.53 ha) is

less, being 89% of the project footprint of these Scheme components in Area 2.

Therefore, the proposed activity is not considered to have any long-term detrimental

effect on vegetation surrounding the proposed site and other than in the construction

phase, is a benign activity that would not affect the wider area in any way. Natural

regeneration should occur across any areas affected by construction (except those

areas occupied by structural components).

Access road construction to the powerhouse accounts for the majority of vegetated

area potentially affected by the Scheme in Area 2 and traverses the largest diversity of

vegetation types. While no uniqueness in terms of overall vegetation type(s) is

attributable to the general area in which the proposed access road is located, defining a

route that results in least damage to all vegetation, and especially large (60+ cm dbh)

hardwood trees and podocarp trees (30+ cm dbh) will be a priority. Field observations

indicate trees of these sizes are in very low densities in all vegetation types likely to be

affected by access road construction. Relatively easy terrain of the landforms where

any of this infrastructure construction is likely should allow some route variation if

required. Tree avoidance should be achievable.

Vegetation types present in riparian margins in this area are not unique or

distinguished floristically from their counterparts not occupying a riparian strip. It is

the arbitrary riparian designation of fixed-width distance from stream bank, not

vegetation, that distinguishes these zones and that may have environmental planning

restrictions that would not otherwise apply. For streams 1 – 3 metres wide provisions

of the Proposed Regional Land and Water Plan (WCRC, 2013) prescribe 10 metre

wide riparian margins if dominant slope angle is >12o and 5 metre wide riparian

margins otherwise. This requirement will add some (expected to be relatively minor)

area to available estimates of affected riparian area, however the detailed field survey

and mapping of small stream location was not a component of work undertaken as the

basis of this report. The number and exact location of streams 1 - 3 metres wide that

are potentially affected will need to be determined for regional planning provision

purposes, although it is not considered that potential effects on vegetation will be any

greater than already assessed and considered.

82

Effects of the Scheme on the Area 2 vegetation (being classed as significant

indigenous vegetation under the Westland District Plan (WDC, 2002) criteria of

intactness and size of area, and protected status) and any contribution to high natural

heritage values under the West Coast Conservation Management Strategy 2010 – 2020

(DOC, 2010) criteria of intactness and viability are likely to be minor, considering:

o the small amount of clearance that will occur (Scheme project footprint of 3.96

hectares in Area 2) within the surrounding contiguous indigenous forest

vegetation assemblage cover of the Base Area of c. 385 hectares;

o the narrow, linear footprint of the access road/transmission line combined with

measures to be implemented wherever practicable that avoid affecting

important habitat components e.g. large forest trees; and,

o a low likelihood of any vegetation disturbance post-construction.

83

Acknowledgements

The services of James Bentley and Corey Murray, Boffa Miskell Ltd., Christchurch, for

mapping and GIS analysis, and Martin Kennedy, West Coast Planning Ltd., Paroa, for review

and advice on components of this report, are acknowledged, with thanks.

References

Boffa Miskell Ltd. (2014). Waitaha Hydro Scheme: Natural Character, Landscape and Visual

Amenity Effects. (Report prepared by Boffa Miskell for Westpower Ltd.). Boffa Miskell Ltd.,

Christchurch, New Zealand. Unpbl.

Buckingham, R. (2014). Proposed Waitaha Hydro Scheme: Assessment of the Potential

Environmental Effects of the Proposed Waitaha Hydro Scheme on Terrestrial Vertebrate

Fauna (Bats and Birds) (internal report prepared for Westpower Ltd.). Wildlife Surveys Ltd.,

Mapua, New Zealand. Unpbl.

de Lange, P. J., Rolfe, J. R., Champion, P. D., Courtney, S. P., Heenan, P. B., Barkla, J. W.,

Cameron, E. K., Norton, D. A., & Hitchmough, R. A. (2012). New Zealand Threat

Classification Series 3 – Conservation Status of New Zealand Indigenous Vascular Plants.

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Wardle, P. (1991). Vegetation of New Zealand. Cambridge University Press, New York,

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List of Appendices

Appendix A Map 1: Project Area General Location.

Appendix A Diagram 1: Headworks Infrastructure Concept.

(Diagram supplied by Geotech Consulting Ltd. via Westpower

Limited. N.B: Not intended as a scale drawing. Scale on A3

copy herewith is c. 1:1260 and is indicative for concept

purposes only).

Appendix A Map 2: Infrastructure Locations and Vegetation Type Delineations –

Area 1.

Appendix A Map 3: Infrastructure Locations and Vegetation Type Delineations –

Area 2.

Appendix A Map 4: Wilberg Ecological District and Waitaha Catchment With

LCDB Land Cover Types.

Appendix A Map 5: Base Area Delineation on Topographic Mapping.

Appendix A Map 6: Base Area LCDB Land Cover Types.

Appendix B: Species List with Maori and Common Names

85

Appendix A Map 1: Project Area General Location.

86

87

Appendix A Diagram 1: Headworks Infrastructure Concept.

88

89

Appendix A Map 2: Infrastructure Locations and Vegetation Type Delineations – Area 1.

90

91

Appendix A Map 3: Infrastructure Locations and Vegetation Type Delineations – Area 2.

92

93

Appendix A Map 4: Wilberg Ecological District and Waitaha Catchment With LCDB Land Cover Types.

94

95

Appendix A Map 5: Base Area Delineation on Topographic Mapping.

96

97

Appendix A Map 6: Base Area LCDB Land Cover Types.

98

99

Appendix B: Species List with Maori and Common Names

Note: nt = not threatened. For higher plants status is ex de Lange et al. (2012), for

mosses/liverworts from Hitchmough et al. (2007).

Note: * denotes exotic species.

Large Trees

Botanical Name Maori Name (& other Common Name) Status

Dacrydium cupressinum Rimu (Red pine) nt

Dacrycarpus dacrydioides Kahikatea (White pine) nt

Griselinia littoralis Kapuka (Broadleaf) nt

Libocedrus bidwillii Kaikawaka (New Zealand cedar) nt

Metrosideros umbellata Rata (Southern rata) nt

Podocarpus hallii Totara-kiri-kotukutuku (Hall’s totara) nt

Prumnopitys ferruginea Miro (Brown pine) nt

Quintinia acutifolia Tawheowheo (Westland Quintinia) nt

Weinmannia racemosa Kamahi nt

Smaller Trees/Shrubs


Archeria traversii (Shrubby mountain heath) nt

Aristotelia serrata Makomako (Wineberry) nt

Ascarina lucida Hutu nt

Carmichaelia arborea (Tree broom) nt

Carpodetus serratus Putaputaweta (Marble leaf) nt

Coprosma areolata (Thin leaved coprosma) nt

Coprosma elatirioides - nt

Coprosma ciliata - nt

Coprosma colensoi - nt

Coprosma foetidisima Hupiro (Stinkwood) nt

Coprosma grandifolia Raurekau (Large-leaved coprosma) nt

Coprosma linariifolia Mikimiki (Yellow-wood) nt

Coprosma lucida Karamu nt

Coprosma propinqua Mingimingi nt

Coprosma rhamnoides - nt

Coprosma rotundifolia - nt

Coprosma rubra - nt

Coprosma rugosa - nt

Coprosma tayloriae - nt

Coriaria arborea Tutu nt

Dracophyllum longifolium Inaka (Turpentine scrub) nt

Fuchsia excorticata Kotukutuku (Tree fuchsia) nt

Hebe salicifolia Koromiko nt

Hedycarya arborea Porokaiwhiri (Pigeonwood) nt

Leycesteria formosa*9 Himalayan honeysuckle *

9 Note: Leycesteria formosa was not observed in any area during fieldwork. It is included here because it is

discussed in Section 10.0 as a possible weed risk.

100

Appendix B: Species List Ctd.

Smaller Trees/Shrubs Ctd.


Melicytis ramiflorus Mahoe (Whitey wood) nt

Myrsine divaricata Mapou (Weeping mapou) nt

Myrsine australis Matipou (Red mapou) nt

Neomyrtus pedunculata Rohutu nt

Olearia arborescens (Tree daisy) nt

Olearia avicenniifolia (Mountain akeake) nt

Olearia ilicifolia Hakeke (Mountain holly) nt

Pennantia corymbosa Kaikomako nt

Phyllocladus alpinus (Mountain toatoa) nt

Pseudopanax anomalus - nt

Pseudopanax colensoi Orihou (Three finger) nt

Pseudopanax crassifolius Horoeka (Lancewood) nt

Pseudopanax simplex Haumakoroa nt

Pseudowintera colorata Horopito (Pepperwood) nt

Schefflera digitata Pate (Seven finger) nt

Ulex europaeus* (Gorse) *

Tree Ferns/Ferns/Fern Allies


Asplenium bulbiferum Pikopiko (Hen and chickens fern) nt

Asplenium flaccidum Raukatauri (Hanging spleenwort) nt

Asplenium polyodon (Sickle spleenwort) nt

Blechnum chambersii Nini (Lance fern) nt

Blechnum colensoi Peretao (Colenso’s hard fern) nt

Blechnum discolor Piupiu (Crown fern) nt

Blechnum fluviatile Kiwakiwa (Creek fern) nt

Blechnum sp. “black spot” Kiokio (Palm-leaf fern) nt

Blechnum penna-marina (Little hard fern) nt

Ctenopteris heterophylla (Comb fern) nt

Cyathea smithii Katote (Soft tree fern) nt

Dicksonia squarrosa Wheki (Rough tree fern) nt

Grammitis billardieri (Common strap fern) nt

Grammitis magellanica (Strap fern) nt

Histiopteris incisa Mata (Water fern) nt

Hymenophyllum demissum Irirangi (Filmy fern) nt

Hymenophyllum multifidum (Much divided filmy fern) nt

Hymenophyllum revolutum (Filmy fern) nt

Hymenophyllum spp. (Filmy ferns) nt

Hypolepis rufobarbata - nt

Lastreopsis hispida (Hairy fern) nt

Leptolepia novae-zelandiae (Lace fern) nt

Leptopteris superba Heruheru (Prince of Wales fern) nt

Lycopodium volubile Waewaekoukou (Climbing clubmoss) nt

101


Tree Ferns/Ferns/Fern Allies Ctd.


Paesia scaberula (Ring fern, Scented fern) nt

Phymatosorus diversifolius Kowaowao (Hound’s tongue) nt

Pneumatopteris pennigera Piupiu (Gully fern) nt

Polystichum vestitum Punui (Prickly shield fern) nt

Pteridium esculentum Rarauhe (Bracken fern) nt

Rumohra adiantiformis (Leathery shield fern) nt

Sticherus cunninghamii Waekura (Unbrella fern) nt

Tmesipteris tannensis (Chain-fern) nt

Trichomanes reniforme Raurenga (Kidney fern) nt

Trichomanes venosum (Veined filmy fern) nt

Climbers/Spreading/Perching


Dendrobium cunninghamii Pekapeka, Winika (Christmas orchid) nt

Freycinetia baueriana subsp. banksii Keikei nt

Metrosideros diffusa Akatea (White climbing rata) nt

Metrosideros fulgens (Rata vine) nt

Metrosideros perforata Akatea (White rata) nt

Ripogonum scandens Kareao (Supplejack) nt

Rubus cissoides Tataramoa (Bush lawyer) nt

Rubus parvus (Creeping lawyer) nt

Rubus schmidelioides Tataramoa (Bush lawyer) nt

Sedges/Tussocks/Grasses


Agrostis dyeri - nt

Agrostis tenuis* (Browntop) *

Anthoxanthum odoratum* (Sweet vernal) *

Arthropodium candidum Repehina-papa (Forest floor lily) nt

Astelia fragrans Kahaha (Bush flax) nt

Carex goyenii (Goyen’s sedge) nt

Cortaderia richardii Toetoe nt

Festuca sp. (Fescue tussock) nt

Gahnia sp. (Giant sedge) nt

Hierochloe novae-zelandiae (Holy grass) nt

Holcus lanatus* (Yorkshire fog) *

Microlaena avenacea (Bush rice grass) nt

Phormium cookianum Wharariki (Mountain flax) nt

Poa colensoi - nt

Poa sp. (Annual poa) nt

Rytidosperma setifolium (Bristle tussock) nt

Schoenus pauciflorus (Sedge grass) nt

Trisetum tenellum - nt

102


Sedges/Tussocks/Grasses Ctd.


Uncinia sp. (Hookgrass) nt

Uncinia uncinata (Hookgrass) nt

Herbaceous/Ground Cover


Acaena anserinifolia Piripiri (Bidibid) nt

Anisotome hastii (Haast’s carrot) nt

Cardamine debilis (N.Z. Bitter cress) nt

Celmisia coriacea Tikumu (Mountain daisy) nt

Cirsium palustre* (Marsh thistle) *

Cirsium arvense* (Californian thistle) *

Epilobium pedunculare (Creeping willowherb) nt

Forstera tenella - nt

Geum leiospermum (Mountain avens) nt

Gingidia montana (Mountain anise) nt

Gunnera monoica - nt

Hypochoeris radicata* (Catsear or flatweed) *

Hyrocotyle moschata (Hairy pennywort) nt

Hydrocotyle novae-zelandiae (Pennywort) nt

Lotus pedunculatus* (Lotus) *

Luzuriaga parviflora Nohi (Lanternberry) nt

Nertera ciliata - nt

Nertera depressa (Bead plant) nt

Nertera vilosum - nt

Parahebe lyallii (Lyall’s speedwell) nt

Plantago lanceolata* (Narrow leaved plantain) *

Pratia angulata Panakenake nt

Ranunculus repens* Buttercup *

Raoulia tenuicaulis Tatahuna (Mat daisy) nt

Stellaria media* (Chickweed) *

Traxacum officinale* (Dandelion) *

Trifolium repens* (White clover) *

Viola filicaulis (Forest violet) nt

Mosses/Liverworts


Cyathophorum bulbosum Moss nt

Dawsonia superba Giant moss nt

Dendroligotrichum dendroides Giant moss nt

Hymenophyton flabellatum Liverwort nt

Hypopterygium novae-seelandiae (Umbrella moss) nt

Marchantia berteroana (Thallose liverwort) nt

Monoclea forsteri (Thallose liverwort) nt

103


Mosses/Liverworts Ctd.


Mniodendron dendroides (Umbrella moss) nt

Schistochila appendiculata (Liverwort) nt

Schistochila nobilis (Liverwort) nt

Weymouthia mollis (Hanging moss) nt

Documents

Waitaha Hydro Scheme Terrestrial Flora Description and Assessment … 15 - WHS... · Waitaha Hydro Scheme Terrestrial Flora Description and Assessment of Effects Prepared By: TACCRA