River Action Plan for the Lower Collie River 2008
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River Action Plan for the Lower Collie River Prepared for Leschenault Catchment Council by Leigh Shinde-Taylor Funded by the Natural Heritage Trust (NHT) and National Action Plan for Salinity and Water Quality (NAP), these are joint initiatives of the State and Australian Government, which are administered by the South West Catchments Council.
How to use this river action plan This River Action Plan (RAP) was prepared for the Leschenault Catchment Council and landholders within the Lower Collie River catchment. It contains a detailed description of the current health of the waterway, provides information on current management issues, and recommends strategies to address the issues. Landholders may find this a useful tool to help manage their waterways, while community groups may find it helpful in prioritising actions to make the best use of limited resources. For others, it will provide background information to aid decision making. For Landholders Landholders should turn to their relevant map in Chapter 5 and read the associated management issues and recommendations. They should then read Chapter 4 to determine why these issues are considered to be a priority for remediation, and Chapter 6 to determine the most appropriate actions to address the issues. Information on the general study area and methodology used to develop this action plan can be found in Chapters 1, 2 and 3. For the Leschenault Catchment Council Turn to Chapter 5 as it contains detailed information on management issues for each stretch of the waterway. Chapter 6 provides technical advice on how to best address and manage these management issues, and relevant pages should be read carefully prior to implementing any actions. Seven appendices provide further information that may be useful to landholders and community groups. • Native vegetation of the Collie River Catchment • Common weeds found in the study area • Planning advice from the Vasse River Action Plan • Permits Required Prior to Commencing Works In Rivers • Landcare Project Time Line • Best Management Practice (BMP) • Useful contacts and phone numbers Acronyms RAP River Action Plan LCC Leschenault Catchment Council NHT Natural Heritage Trust DEC Department of Environment and Conservation (previously CALM) WRC Water and Rivers Commission (now DoW) DoW Department of Water (previously DoE) CALM Department of Conservation and Land Management (now DEC) DoE Department of Environment (now DoW) i
Acknowledgments Cover photo: Lower Collie River, photo taken by Peter Taylor Thanks to Martin Olney from the Regional Support Branch of the Department of Environment for preparing This River Action Plan was developed in consultation the maps. Special thanks to Jason Foster from with Leschenault Catchment Council, and thanks are Department of Environment and Conservation for extended to the community group for their assistance. providing information on the Wellington National Park. Special thanks to Bree Skenner, Cassandra Jury, Mike McKenna, Cameron Sutherland and Debbie Blake for Last but not least, I would like to express thanks to their technical support. Peter Taylor, Robin Taylor and the Shinde family for their assistance in field assessments. All of the landholders involved in the project, especially those who took the time and effort to help with the This River Action Plan has drawn extensively from the foreshore assessments and provide anecdotal and work of Genevieve Hanran-Smith in the Margaret River historical information, deserve a big thank you, as do and, the Sabina, Abba and Ludlow Action Plans and those who attended the community workshops and John McKinney’s work in the River Action Plan for meetings. Special thanks to members of the community Ellen Brook . that assisted in the foreshore assessments using canoes. The project was funded by the Natural Heritage Trust Shirley Fisher and Mark Kennedy of the Leschenault and National Action Plan for Salinity and Water Quality, Community Nursery assisted in the compilation of the these are joint initiatives of the State and Australian species lists. Thanks also to Mel Strang of the Government, which are administered by the South West Leschenault Catchment Council for help with plant Catchment Council. identification. Reference details Thanks to Tom Rose, Alan Pastega, Rosemary Lerch and Artemis Kitsios from the Department of Water for The recommended reference for this publication is: providing water quality data and information. Bill Leschenault Catchment Council, 2008, River Action Bennell and Joe Northover are gratefully acknowledged Plan for the Lower Collie River, Leschenault Catchment for their assistance in compiling the Indigenous heritage Council. of the area. ISBN: 978-0-9803056-3-0 ©Copyright - Leschenault Catchment Council Inc Permission to copy all or any part of this report is granted where the intention is not for commercial gain, and provided the source is acknowledged. Disclaimer: While this document has been prepared in good faith and with all due care, servants and officers of the Leschenault Catchment Council and contributing Western Australian government departments and agencies accept no responsibility for its accuracy, currency or reliability or correctness caused by changes in circumstances after the time of publication or collection of the information in so far as it incorporates information provided by a second or third party. Users of the document should obtain advice and conduct investigations and assessments of any proposals that are being considered in the light of individual circumstances. ii
Contents How to use this River Action Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii For landholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii For the Leschenault Catchment Council . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ii Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 General recommendations to improve the health of the lower Collie River . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Background. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Study aims . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2. Study area. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 The river system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Climate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Landforms and Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Threatened Flora and Fauna . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Heritage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 3. Study methodology. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 River foreshore condition assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Community involvement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 4. Management issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18 Water Quality Issues. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Erosion & Sedimentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Stock access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Loss of native fringing vegetation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Weed invasion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 5. River foreshore condition and recommendations for management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Using the maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Management recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Reach 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Reach 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Reach 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 Reach 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30 6. Management advice - What can be done? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Where to start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Stock control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Water quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Erosion control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 Regeneration and revegetation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Weed control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Feral animal control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 iii
7. Implementation of Management Techniques on the Lower Collie River . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 8. References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48 Appendix 1. Native vegetation of the Lower Collie River Catchment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51 Appendix 2. Common weeds found in the study area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53 Appendix 3. Planning advice from the Vasse River Action Plan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55 Appendix 4. Permits Required Prior to Commencing Works in Rivers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58 Appendix 5. Landcare Project Time Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60 Appendix 6. Best Management Practice (BMP). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61 Appendix 7. Useful contacts and phone numbers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 LIST OF FIGURES Figure 1 Study area Figure 2 Annual total rainfall for south west Western Australia Figure 3 Loads, Status and Medians in the Collie Catchment (From DOE, 2006) Figure 4 The correct placement of fences in relation to the river valley Figure 5 Outside bend bank erosion Figure 6 The use of structural works will prevent the process of undercutting Figure 7 The process of bank slumping caused by excessive weight and lack of support Figure 8 Repositioning large woody debris LIST OF DIAGRAMS Diagram 1 The four grades of river foreshore condition – (A) pristine to ditch (D) LIST OF TABLES Table 1 Summary Foreshore Condition rating for Lower Collie River Table 2 Length of fenced areas of Lower Collie River Table 3 Water Quality Data for Lower Collie River iv
Summary The Collie River is located in the Leschenault General recommendations to improve Catchment area. The Collie River has a catchment of the health of the lower Collie River 2920 square kilometres it extends approximately 154km inland from the coast. The river is generally referred to It is recommended that landholders consider the as the Upper Collie River (the section above the following: Wellington Dam) and the Lower Collie River (below the • Retain and protect the remaining riparian vegetation Wellington Dam). This study is of the Lower Collie of lower Collie River; River that is approximately 45km in length and discharges into the Leschenault Estuary near Eaton. • Fence the river to better control stock access; The aim of this RAP is to provide information to • Use available funding to contribute towards the landholders, interested community members, and costs of fencing and rehabilitation projects; organisations on the health and current state of the • Control weeds, particularly invasive species in the Lower Collie River and recommendations on how to riparian zone; improve its management for the future. • Implement best management practices that Assessments were carried out in September and October minimise soil erosion and nutrient loss to waterways 2007 using the Foreshore Condition Assessment such as soil testing and maximising vegetation cover method developed by Dr Luke Pen and Margaret Scott on the soil; for rivers in the South-West of Western Australia (Pen & Scott, 1995). Many landholders assisted with the • Revegetate waterways with local native species to foreshore surveys. provide habitat and enhance ecological function; A summary of the foreshore condition ratings and • Use available funding and resources to control feral length of fencing of the river is presented in Tables 1 animals. and 2. It is recommended that the Leschenault Catchment Key issues identified Council consider the following: The key issues of concern identified during the • Encourage and support community efforts to fence foreshore assessments and community consultations the River to restrict stock access; were: • Apply for further funding to continue to subsidise • Loss of native fringing vegetation and degradation of the cost of revegetation projects and fencing; remaining vegetation; • Encourage, as a priority, the protection of areas of • Weed invasion; the river still retaining native fringing vegetation. It is more cost effective to protect these areas now than • Erosion and sedimentation of the waterway; to restore them later after further degradation has • Water quality issues, including nutrient enrichment, occurred; pollution and salinity; • Provide encouragement and support to landholders • Impact of urban development on the water quality; to undertake revegetation using a diverse suite of local native species (including trees, shrubs, sedges, • Need for assistance if landholders are to protect and rushes, herbs and native grasses); enhance the foreshore by fencing or revegetating; • Expand and continue to support weed and feral • Impact of feral animals; animal control projects in the catchment; • Impact of tourists and visitors to public areas. page 1
• Promote best management practice techniques that • Promote the use of “clean site” building techniques minimise soil erosion and nutrient loss to waterways to reduce the impact of urban development on the such as buffer strips, soil testing and fertiliser water quality of the Lower Collie River; management plans, and maximising vegetation • Encourage local government and developers on the cover on the soil; Lower Collie River to implement Foreshore • Work with landholders, and engineers from the Management Plans in an effective manner; Department of Environment to address serious • Encourage the use of Environmental Water erosion and sedimentation problems; Requirements when determining water extraction • Work with Department of Environment to expand and allocations; their water monitoring program of the Lower Collie • Encourage the use of Best Management Practices on River to address community concerns in regards to rural drains; nutrient levels, contamination and salinity; • Encourage the implementation of the Wellington • Encourage the use of Water Sensitive Urban Design National Park and Westralia Conservation Park in new and existing residential developments; Draft Management Plan 2005. Condition Total Length Total % A (pristine) 15.8km 35% B (weedy) 9km 20% C (erosion prone/eroding) 19km 42% D (ditch) 1.2km 3% Table 1: Summary of foreshore condition rating of Lower Collie River Length Fenced % Of Length North/Right Bank (facing downstream) 9.1km 20 % South/Left Bank (facing downstream) 15.5km 32.8 % Total Fenced 24.6km 26.5 % Table 2: Length of fenced areas on Lower Collie River page 2
1. Introduction Background Study Aims The Leschenault Catchment Council is an incorporated The primary aims of this River Action Plan are: community-based body that works in partnership with • To produce a detailed description of the current state government agencies, local government, industry and of the Lower Collie River and identify priority community groups to share awareness and actions which guide works and help improve the responsibilities in determining natural resource health of these waterways; management issues and their solutions within the catchment. • To help increase the community’s awareness of the importance of healthy waterways and riparian The Council was formed in 2000, through the vegetation; amalgamation of two community-lead NRM groups - the Leschenault Inlet Management Authority and the • To provide a benchmark against which the local Leschenault Catchment Coordinating Group. It has ten community’s future catchment work, to protect and community, two local government, two industry and rehabilitate the waterways, can be gauged; two State government representatives and links to many other groups. • To provide guidance on the possibility of funding and assistance available for fencing, weed and The Leschenault subregional boundaries encompass the erosion control, and the planting and rehabilitation Leschenault Estuary and the Preston, Collie, Ferguson, of native vegetation; and Wellesley and Brunswick River systems and the Wellington Dam and its catchment, the upper Collie • To provide a sound technical basis for future funding River. or project submissions. Its charter is: ‘To develop ways to achieve a sustainable, healthy and productive catchment in partnership with the community.’ In recognition of the need to address the poor state of the rivers in the South West region, the project was funded by South West Catchment Council through the Improving Waterways Health Program of the SW Investment Plan, the basis of this program is: “To bring about the improvement of the health of the Regions waterways” page 3
2. Study area page 4 Figure 1: Study area.
Catchment Description many farmers water their stock and orchards from the River. The Lower Collie River and its tributaries were The Lower Collie River starts at the Wellington Dam proclaimed under the RIWI Act in 1954 , thus all and flows through approximately 10.5km of pristine surface water abstraction from the river and tributaries National Park before reaching Burekup Weir. The require a licence from DoW. However, stock watering Catchment west of Burekup weir to the Burekup and domestic use are excluded from licensing as a townsite can be described in general as undulating hills Riparian right. with medium to high clearing. As the Lower Collie River flows west from Burekup to Australind Bypass, Upstream of the Burekup Weir, Wellington National passing across the Swan Coastal Plain, the catchment Park covers the majority of this area. The Wellington quickly becomes flat with a high percentage of clearing. National Park is managed by the Department of The Brunswick River flows into the Collie River at Point Environment and Conservation, and they have recently Latour and the surrounding catchment displays an prepared a Draft Management Plan for the Wellington increase in vegetation as much of the river is protected National Park and Westralia Conservation Park 2005. by foreshore reserves. However, increasing residential Climate development is placing pressure on this river system as it discharges into the Leschenault Estuary. The area has a Mediterranean-type climate, characterised by warm, dry summers and cool, wet The river system winters. The Collie area experiences an average annual For this study, Lower Collie River was considered to rainfall of 940mm (Bureau of Meterology, 2005). include the main channel but does not include its There is data that supports, the anecdotal evidence from tributaries. The Lower Collie River extends landholders, of decreased rainfall. It shows a 10-25 % approximately 45km from the Wellington Reservoir and decline in annual rainfall in the south west of Western discharges into the Leschenault estuary. Australia from the long-term climate mean (Hennessy, The Lower Collie River is classified as a “T3” river type 2002). Figure 2 shows that since circa 1970 there has which means it’s a “shorter river originating in the been a clear reduction in total annual rainfall. This is higher rainfall Jarrah/Marri forest before descending the due to a reduction in the mean number of raindays, and Darling Scarp to the coastal plain to the sea” (WRC the mean number of heavy raindays in winter. 2/92) According to the State Water Strategy (Government of Western Australia, 2003) ‘Climate change has Approximately 45km of foreshore was assessed and the contributed to a 10-20 percent reduction in rainfall in location of the study area is shown in Figure 1. the south-west of the State over the last 28 years, a subsequent 40-50 percent reduction in run-off into our Landuse Description dams and reduced recharge of groundwater’. Urban development fringes the Lower Collie River west of the Australind Bypass, the river foreshore in this area being vested with the Shire of Harvey (right foreshore), Shire of Dardanup (left foreshore) or State Government. The major landuse east of the Australind Bypass is beef and sheep farming with one Turf Farm near the South West Highway. Landuse upstream from the highway is again mainly beef farming, however there is an increase in orchards (mainly citrus) and one winery. The majority of the river foreshore is privately owned and page 5
1300 10-year moving average 1200 1110 1000 Annual Rainfall (mm) 900 800 700 600 500 1884 1894 1904 1914 1924 1934 1944 1954 1964 1974 1984 1994 Figure 2: Annual total rainfall for south west Western Australia. Source Hennessy (2002). Landforms and Soils sand dunes and sandplains with flats and swamps. The geology is sandy alluvium over sedimentary rocks. The The upper catchment soils of the Lower Collie River are soils are pale deep sand, semi-wet soil and wet soil. dominated by Lowden landforms with steep slopes and lateritic soils with rocky outcrops. The lower catchment The Lowden Valleys System on the Western Darling area on the coastal plain is more dominated by the Range, extends from Harvey to Bridgetown. The Pinjarra, Vasse and Bassendean landforms. The landform is deeply incised valleys. The Geology is following description of these landform taken from colluvium over metasediments and granitic rocks. The AgMaps Land Manager 2005, for the shires of soils are friable red/brown loam earths, brown loamy Serpentine-Jarrahdale, Kwinana, Rockingham, earths, loamy gravels, brown deep loamy duplexes, Mandurah, Murray, Boddington, Waroona and Harvey, duplex sandy gravels and stony soils. can be seen below. Vegetation communities The Pinjarra System extends along the Swan Coastal Known Vegetation Complexes taken from Regional Plain from Perth to Capel. The landform is poorly Forest Agreement Vegetation Complexes, (Mattiske and drained coastal plain. The geology is alluvium over Havel 1998) sedimentary rock. The soils are semi-wet soils, grey deep sandy duplexes, brown loamy earths, pale sands Upper Catchment and clays. Murray 1 - Open forest of Eucalyptus marginata subsp. The Vasse System extends along the Swan Coastal Plain marginata - Corymbia calophylla- Eucalyptus patens from Perth to Dunsborough. The landform is estuaries, (blackbutt) on valley slopes to woodland of Eucalyptus swampy depressions and poorly drained flats. The rudis - Melaleuca rhaphiophylla on the valley floors in geology is alluvium over sedimentary rocks. The soils humid and sub-humid zones. are wet soils and pale deep sands. Helena 1 (He1) - Mosaic of open forest of Corymbia The Bassendean System also extends along the Swan calophylla-Eucalyptus patens-Eucalyptus marginata Coastal Plain, from Busselton to Jurien. The landform is subsp. marginata with some Eucalyptus rudis on the page 6
deeper soils ranging to closed heath and lithic complex Areas of blackberry and briar rose infestations have on shallow soils associated with granite on steep slopes been known to be attractive to possums as they can of valleys in humid and subhumid zones. provide food and extra protection from predators. Lowdon – Open forest of Corymbia calophylla (marri) - • Common Brushtail possum Trichosurus vulpecula Eucalyptus marginata subsp. Marginata (jarrah) - Agonis (not threatened) outside and within riparian habitat flexuosa (peppermint) with some Eucalyptus wandoo where eucalypt species with hollows are present. (wandoo) and occasional Corymbia haematoxylon • Brushtail Phascogale Phascogale tapoatafa (DEC (mountain marri) on slopes, and woodland of Priority 3) where eucalypt species with hollows are Eucalyptus rudis (flooded gum) - Melaleuca present. rhaphiophylla (swamp paperbark) on valley floors in the humid zone. • Chuditch Dasyurus geoffroii (Vulnerable) have been sighted and they reside in the Jarrah forest where Lower Catchment hollow logs on the ground are present for dens. Swan Coastal Plain Vegetation includes salt-marsh Birds Sarcocornia quinqueflora (bearded samphire), Halosarcia indica (shrubby glasswort), Juncus Kraussii (shore- • Forest Red-tailed Black Cockatoo Calyptorhynchus rush), Melaleuca rhaphiophylla (swamp paperbark), banksii naso (Vulnerable) within adjacent forest. Casuarina obesa (saltwater sheoak), Bolboschoenus caldwellii (club rush) and Eucalyptus rudis (flooded • Baudins White-tailed Black Cockatoo Calyptorhynchus gum). baudinii (Endangered) within adjacent forest. Threatened Flora and Fauna • Eastern Curlew Numenius madagascariensis (DEC Priority 4) at the river mouth. The following information was provided by the Department of Environment and Conservation Office, The species listed above are obtained from DEC Bunbury. Corporate and Regional databases and from general knowledge of species occurring in the area. Only those These following threatened species are found in the threatened flora and fauna species within 100m of the study area. Collie River are listed. Threatened Flora Fish and freshwater crayfish • Acacia oncinophylla subsp. Oncinophylla (DEC A fish study was conducted on the Lower Collie River in Priority 3) March 2003 by Wetland Research and Management (WRM) and a Draft Report was prepared for the Waters • Diurus drummondii (Declared Rare Flora) and Rivers Commission. The fish study found five • Lasiopetalum membranaceum (DEC Priority 3) species of native fish, three species of introduced fish and three species of decapods. • Caladenia speciosa (DEC Priority 4) Field sampling showed healthy populations of native Threatened and other Fauna fish including the Freshwater cobbler, Nightfish, Mammals Western minnow, Pygmy perch and Swan River goby. Three species of introduced fish were recorded; the • Southern Brown Bandicoot or Quenda Isoodon Mosquito fish, trout and Redfish perch, but only the obesulus fusciventer (DEC Priority 5) within denser Mosquito fish was abundant (WRM 2004). riparian habitat possibly including weedy areas. Three species of freshwater crayfish (decapods) were • Western Ringtail possum Pseudocheirus occidentalis found in the study. Freshwater prawns were found in (Vulnerable) in pockets of peppermint and where good numbers at sites on the coastal plain, but present eucalypt species with hollows are also present. in low numbers further upstream. Marron were most page 7
visible in the upper reaches of the river and very few This story told by John Sara with special thanks to gilgies were caught overall. The low numbers of gilgies George E Webb (dec), elder Wardandi Tribe Busselton may reflect effects of poor water quality and low habitat and Joseph Northover, Collie Nyungar. condition (WRM 2004). The entire Collie River is considered scared and is a However, overall the water quality was found to be registered mythological site under the Aboriginal reasonable at all sites surveyed by WRM, apart from a Heritate Act. slightly elevated salinity. In general the upper reach (upstream on Burekup weir) had high summer flows, European heritage deep pools, minimal siltation and supported a high In 1829 Dr Alexander Collie and Lieutenant William loads on large woody debris. Where the lower reach Preston jointly discovered the Collie and Preston Rivers, was much more degraded in which pool were infilling giving their surnames to the respective rivers. Dr with silt accumulations (WRM, 2004). Alexander Collie could hardly have foreseen that a town, some 40 km upstream from his nearest contact Heritage would also take his name (Williams 1979). The Lower Collie catchment has significant Indigenous Further exploration of the river occurred a year later and non-Indigenous cultural heritage values. when Lieutenant Governor Sir James Stirling expedition Indigenous heritage recognised the potential of the land for agricultural. The Collie River Valley was later used for beef and sheep The Aborigines of the South West Region, prior to grazing. In the early 1880’s coal was found near the European contact, formed a distinctive socio-cultural river and by the late 1880’s the area around Collie was group collectively known as Nyungar (O’Connor et al., recognised for its coal resources (CALM, 2005). 1995). A painting by John Sara tells the story of how the Ngarngungudditj Wargal or Hairy Faced snake came Collie has grown to be one of the most important down from the north of Collie a long time ago, to form mining towns in the State, supplying coal and from the Rivers within the Leschenault Catchment. 1961 for the generation of electricity (CALM, 2005). Following the discovery of coal and the development of “The snake came down through Collie creating the hills transport facilities the increased infrastructure and rivers down to Turkey Point (Australind- Pelican stimulated the timber industry (Williams, 1979). The Point area) and Eelaap (Bunbury). He pushed his big mills provided timber to the mining industry and the body and turned to form the estuary and Koombana Bay. railways, two of these mills that began operation in the He then came back up the Collie River to a place called 1940’s are still in operation today (CALM, 2005). Minninup pool. When the moon is high in the sky you can see his spirit resting there. In 1931 the Wellington Dam was constructed for the Collie Irrigation Scheme, at the time of its construction Koombana Bay (before the Breakwater Rocks had it was the largest dam in Western Australia (CALM begun) was a beautiful sea bay front from the ocean and 2005). Turkey Point was an Aboriginal ceremony camping hunting and corroboree ground. The Wargal is the great mythical snake that controls the lives, actions, totems and beliefs of the Nyungar people” page 8
3. Study methodology River foreshore condition assessment C grade foreshore: Erosion prone to eroded The Pen-Scott method of riparian zone assessment was C1 Erosion prone - trees remain, possibly with some used for the foreshore assessment. This system provides large shrubs or grass trees, but the understorey a graded description of the river foreshore from pristine consists entirely of weeds, mainly annual grasses. (A grade) through to ditch (D grade). A summary of the Most of the trees will be of only a few resilient or grades of the Pen-Scott system follows (Pen & Scott, long-lived species and their regeneration will be 1995; Water and Rivers Commission, 1999a). These are almost negligible. In this state, where short-lived illustrated in Figure 3 and photos on the following weeds support the soil, a small increase in physical pages. This method allows comparisons of waterway disturbance will expose the soil and render the river health across the south west of Western Australia, and valley vulnerable to serious erosion. can be used to prioritise actions. C2 Soil exposed - annual grasses and weeds have A grade foreshore: Pristine – near pristine been removed through heavy livestock damage and A1 Pristine - embankments and floodway are grazing, or other impacts such as a result of entirely vegetated with native species and there is recreational activities. Low level soil erosion has no evidence of human presence or livestock begun, by the action of either wind or water. damage. C3 Eroded - soil is being washed away from A2 Near pristine - native vegetation dominates but between tree roots, trees are being undermined and introduced weeds are occasionally present in the unsupported embankments are subsiding into the understorey, though not to the extent that they river valley. displace native species. A3 Slightly disturbed - areas of localised human D grade foreshore: Ditch to drain disturbance where the soil may be exposed and weed density is relatively heavy, such as along D1 Ditch, eroding - fringing vegetation no longer walking or vehicle tracks. Otherwise, native plants acts to control erosion. Some trees and shrubs dominate and would quickly regenerate in remain and act to retard erosion in certain spots, but disturbed areas should human activity decline. all are doomed to be undermined eventually. D2 Ditch, freely eroding - no significant fringing vegetation remains, and erosion is completely out of B grade foreshore: Weed infested but tree cover control. Undermined and subsided embankments still largely present are common, as are large sediment plumes along the B1 Degraded, understorey mainly natives - weeds river channel. have become a significant component of the D3 Drain, weed dominated - the highly eroded river understorey vegetation. Although native species valley may have been fenced off enabling remain dominant, a few have probably been colonisation by perennial weeds. The river has replaced or are being replaced by weeds. become a simple drain, similar if not identical to the B2 Degraded, understorey 50% weeds – understorey typical major urban drain. weeds are about as abundant as native species. The regeneration of some tree and large shrub species may have declined. B3 Degraded, understorey weed dominated - weeds dominate the understorey, but many native species remain. Some tree and large shrub species may have declined or have disappeared. page 9
Diagram 1: The four grades of river foreshore condition - (A) pristine to ditch (D). page 10
A Grade foreshore: Note complete vegetation cover which is essential to the health of the waterway. B3 Grade Foreshore: The understory is entirely dominated by weeds (mainly watsonia), but many native trees still remain. page 11
C3 Foreshore. Note the extensive bank erosion and the understorey consists entirely of annual weeds. D3 Grade Foreshore: The channel has eroded away over time, leaving a weed (mainly annual grasses) infested drain. No native vegetation occurs at all on these banks. page 12
Community involvement • Weeds – with particular reference to blackberry and cottonbush; Community involvement is an integral component of River Action Plans. Every effort was made to involve the • Erosion – erosion of river banks and the need for community at each stage of the process from initial fencing the foreshore to prevent stock access; assessments to developing management recommendations. • Water Quality – the impact of agriculture, urban Most of the assessments were conducted with the development and rural drains on the water quality of landholders, and they provided invaluable historical the river; and anecdotal information about the catchment. • Feral Animals –fox and rabbits in particular; Importantly they expressed their views, explained what their concerns were, and why and how they felt the • Decline in fish species – marron and cobbler waterway should be managed. numbers have reduced; Once the foreshore assessments were completed, a • Sedimentation –sediment build up in the river and community workshop (on the 5th of March 2008) was estuary; held to present initial findings and to seek feedback about the project and management recommendation • Fire Hazard – with particular reference to bamboo from the community. The community representatives at and other weeds along the foreshore providing a the workshop were asked to provide information about hazard for fire. what they felt were the major management issues on the These community concerns and management issues Lower Collie River. The following points (in order of have been addressed in more detail in Chapter 4. priority) were raised by the community; • Lack of Water – the Wellington dam and irrigation having an impact on environmental flows; page 13
4. Management issues There are a number of management issues in the Lower In 2003, the Department of Environment commissioned Collie River Catchment. They vary according to a study of EWR’s on the Lower Collie River. The study landform and soils, past and current land use and concluded that water flow of the river should not be management practices. These interrelated issues are altered as changes in the order of 10cm of more could summarised below. result in the loss of the important sheath twigrush fringing sedgelands. This sheath twigrush species is Water extraction and allocation found in healthy numbers in the Wellington National Under the Rights in Water and Irrigation Act 1914 Park downstream of the Dam through to Burekup Weir. ‘riparian rights’ allow landholders to take water for This species is of particular importance as it is a habitat specific non-commercial purposes such as domestic use, for fish spawning and also provides stabilisation to the or non-intensive stock watering (Water and Rivers river banks preventing erosion (Syrinx, 2003). Commission, 2001). Extracting water for commercial The 2003 Synthesis Report on the Lower Collie River purposes or in excess of riparian rights may require a EWR’s found that further research and monitoring licence from the DoW. A number of landholders extract activities are required before implementing a revised water directly from the Lower Collie River for EWR. commercial purposes some of which hold DoW licences. However, there is speculation that a number of Water Quality Issues landholders are taking water without a licence. This is Nutrient Levels an issue for DoW when determining Environmental Water Requirements for the river. There is community concern about the water quality in Lower Collie River. Issues such as nutrient levels, Currently, the largest allocation from the lower Collie eutrophication and fish kill levels in the waterway were River is 68GL to the South West Irrigation Management raised during the foreshore surveys. Much of the Co-operative Ltd to extract water from the Burekup concern was about the fish kills that have occurred in Weir, which obtains its supply from the Wellington the past, and what caused the fish kills. Dam. This water is used for the irrigation of the Collie River Irrigation District, which stretches from Benger to High nutrient levels in the lower Collie River play an Dardanup, comprises of 267km of channels and important role in how these fish kills occur. Nutrient supplies water to 470 farms (CALM, 2005). levels in the river range from moderate to high levels of nitrogen and phosphorus. Nitrogen (N) and The Wellington Dam currently has a salinity level far phosphorus (P) being two of the most important plant higher than 500mg/l recommended by the World Health nutrients are commonly found in a wide range of Organisation Guidelines for Drinking Water Quality. fertilisers. Fertiliser runoff from rural and urban land The Collie Catchment has been designated by the State can lead to increased amounts of N and P in the river Salinity Strategy as a recovery catchment and it is system resulting in nutrient enrichment expected that salinity will reduce to a potable level (eutrophication) in the lower reaches of the Collie (500mg/l) by 2015 (Mauger etc 2001). River. Eutrophication is the increase in algae growth Once the water in the Wellington Dam becomes (phytoplankton) which can result in algal ‘blooms’ potable, water allocation demands may increase and it is which in some cases can be toxic to people, stock and likely that water will be extracted for local community’s result in fish kills (DOE, 2005). drinking water allocations. Potentially putting pressure The phytoplankton algal blooms may be associated with on the downstream flow regimes needed to maintain rapid deoxygenation of waters that trigger fish kills. It ecological values and social water needs. is the loss of oxygen that often results in multiple fish Environmental flows deaths and fish are seen to be “gasping for air” at the water surface (DOE, 2005). Fish kills have been Environmental flows are often referred to as Ecological recorded on the lower Collie River in June 2002, 2003 Water Requirements (EWR’s). EWR’s are defined as the and May 2004. water regime needed to maintain ecological values of water dependent ecosystems at a low level of risk (WRC, 2001). page 14
Tables 3 below shows the general water quality within Nutrient data from a more recent report prepared by the the lower Collie River at a monitoring site near Rose Rd. Department of Water in June 2006 indicates a general The data was collected by the Department of increase in nitrogen and phosphorus concentrations as Environment between 2001-2003. The data indicated water moves towards the estuary. Figure 3 below shows high P levels and low N levels. the total Nitrogen (TN) and total Phosphorus (TP) levels at 5 sites along the Lower Collie River. Table 3 Water Quality Data (Lower Collie River, Rose Rd Site 612043) Site ID 612043 Name Collie River Total Nitrogen Period 2001-2003 Median 0.25 Classification low Total Phosphorus Period 2001-2003 Median 0.221 Classification High pH Period 2001-2003 Median 6.9 Classification neutral Trend Decreasing, - 0.132 Colour Period 2001-2003 Median 50 Classification stained No trend Turbidity Period 2001-2003 Median 8.3 Classification moderate Trend No trend Dissolved Oxygen Period 2001-2003 Median 6.7 Classification Low Trend decreasing, -0.22 mg/L Trend Param obs, 1997-2003, MK, Wks 1-52 Total Dissolved Salts Period 2001-2003 Median 860.313 Classification marginal page 15
Figure 3: Loads, Status and Medians in the Collie Catchment (DOE, 2006) TN and TP concentrations at the Rose Rd monitoring There are two broad types of drainage infrastructure – site (612043) are slightly higher than the two sites Rural Main drains as already discussed that are operated upstream and approximately half that of the other two and maintained by the Water Corporation and there are monitoring sites downstream. It is likely that the also farm drains. Farm drains manage surface water on- increase in nutrient concentrations downstream could farm and tend to connect with the main drainage be caused by inputs from the Henty Brook system. This network, these are not the responsibility of the Water catchment is hilly and mostly cleared with cattle and Corporation (GHD, 2006). beef the dominating landuse. This landuse is The water quality of rural drains depends upon the commonly associated with high export of both Nitrogen various activities that occur within the catchment area and Phosphorus into the waterways (DOE, 2005). of the drainage system. If best agricultural practices are Rural Drains not used then various nutrients, pesticides and sediment can escape the property and enter the Downstream of the Rose Rd monitoring site, there are a drainage system (Water Corporation, 2002). number of rural drains that could also have an impact on water quality in the lower Collie River. Urban Stormwater Drains There are six Water Corporation drainage districts in Rural drains are not the only drainage system that can the lower south west. The Roelands Drainage District have an impact on the water quality of the Lower Collie drains excess water from the low lying areas in the River. Urban stormwater drains into the river and then lower Collie catchment. The drainage system was into the estuary. Stormwater drainage can contain a constructed early in the development of the irrigation number of contaminants such as street litter, fertiliser district to relieve surface ponding and to convey floods loss from lawns, animal wastes, sediments, petrol, oil, and excess irrigation water. and heavy metal from vehicles. page 16
Untreated stormwater can greatly reduce the water resulted in increased creek flows causing significant quality of rivers and waterways, which can then lead to incision and erosion. Disturbance from stock and adverse impacts on the aquatic animals, plants and clearing of fringing vegetation has led to erosion such as ecosystems (DOE, 2005). undercutting and slumping of banks. Issues associated with erosion problems include: Water Sensitive Urban Design (WSUD) promotes the treatment of water prior to discharge from a stormwater • loss of valuable soil; outlet. The LCC, Local Governments and the DoW are • loss of fences as the water course deviates; encouraging developers to utilise the principles of WSUD in new residential developments. For more • poor water quality resulting from increased turbidity information on WSUD contact the Department of and nutrients; Water. • increased flood potential due to silting up of the Salinity channel; Salinity issues of the Wellington Dam are well known, • filling of summer pools; and the State Government has taken action to reduce salinity levels by 2015. The Salinity Situation Statement • losss of habitat for aquatic life; details these actions (Mauger, 2001). • increased channel width and loss of agricultural High salinity levels in rivers can be catastrophic. Not land; only does riparian vegetation die because of salinity, but • reduced visual amenity and recreational sites habitat is lost and plant and animal populations decline associated with the waterways; and (SOE, 2007). • further loss of native riparian vegetation as severe The salinity of the Lower Collie River is higher than erosion problems cause subsidence. (Cape to Cape that of nearby river systems such as the Preston River. Catchments Group, 2005) Sampling in 2000 found that salinity ranged from 950mg/L immediately below the Wellington Dam, The amount of sediment being transported in rivers is reducing to around 600mg/L in the mid reaches of the expressed as total suspended solids (TSS). The river and then rising to approximately 1200mg/l in the Department of Environment has conducted routine lower non estuarine reaches (Welker, 2002). The sampling of TSS. The results indicate that although influence of the estuarine water extends a least a few rivers may have generally low TSS, large amounts of hundred metres upstream to the Australind Bypass. suspended solids are often transported during storm The Leschenault Estuary, along with the estuarine reach events as scouring increases. of the Collie River are classified as conservation category wetlands. After a high rainfall event the sediment transported in the Collie River is likely to be deposited in the Data from the Rose Rd monitoring site (Table 3) Leschenault Estuary, increasing the size of the tidal flats, indicates that salinity is at a moderately low level of covering seagrass beds, increasing turbidity and 860mg/l. The State of the Environment Report WA, reducing water depth (DOE, 2005). Sedimentation of 2007 found that rising salinity trends have been halted the lower reaches of the Collie River and the in the Collie River due to clearing controls and Leschenault Estuary is of great concern to the reafforestation efforts in the Upper Catchement above community, as it can impact on recreational use of the Wellington Dam. river as well as the health of aquatic life. Erosion & Sedimentation While some level of erosion and deposition is natural in any waterway, the acceleration of these processes can cause management problems. As noted previously, wide-scale clearing of vegetation in the catchment has page 17
Stock access the natural and built environment ($104 million) and the amount spent on research and development ($8 Much of the lower Collie River is unfenced, allowing million). It does not include the considerable amount of stock access to riparian vegetation and the River. A volunteer time and labour donated by community number of problems can arise as a result of unrestricted groups and landholders in controlling weeds. stock access. They include: All revegetation activities need to include strategic weed • loss of native fringing vegetation; management actions to increase the survival rate of plantings and to reduce long-term management • weed invasion; activities. If grassy weeds infest a revegetation site, they • compacted soils; will out-compete the native vegetation, and may cause a fire hazard. For more information on weed control, see • nutrient enrichment; the following Chapter. • erosion; and • poor water quality. Loss of native fringing vegetation Parts of the lower Collie River, especially in the upper catchment, the riparian zone has a healthy and complete vegetation structure. However, downstream of Burekup Weir, most of the vegetation is degraded to some degree through weed invasion, clearing, stock access or erosion. In many areas, there is a healthy overstorey of mature trees but little else, while in some areas there is no native vegetation at all. It is important to retain and enhance riparian vegetation as it has many values including; erosion control, dissipating flow, sediment and nutrient retention and providing habitat for many species. Weed invasion Large numbers of weeds were found during the foreshore surveys. Most of these are shown on the maps in Chapter 6. Disturbance through clearing, grazing, erosion and modification of the channel provides ideal conditions for weed growth and spread. The main weeds of concern in the study area were blackberry, watsonia, cotton bush, bridle creeper and grasses such as kikuyu and couch. Weeds compete with native vegetation and restrict natural regeneration. They are a significant factor in the degradation of remnant vegetation and are a major threat to biodiversity. In addition, they are a major economic cost to society. According to a recent study (Sinden et al., 2004) the economic cost of weeds in Australia is approximately $4,000 million annually. This includes the costs of control and losses in output in agricultural land ($3,927 million), the cost of control in page 18
5. River foreshore condition and recommendations for management Using the maps The following page provides an index for the maps, and an overview of the condition of the Lower Collie River. For a summary of the condition rating and percentage of the Lower Collie River that is fenced to exclude stock, please see Table 1 and Table 2 in Summary. Maps 1 to 4 show the Lower Collie River catchment, the main channel and the adjoining land titles. The maps show the foreshore condition of the waterways as assessed using the Pen- Scott method (see Chapter 3 for details of the method of assessment). Weeds and management issues are also shown. A legend is provided. The background aerial photos of the map were taken in 2003 and these are available for purchase from the Department of Land Information (www.dola.wa.gov.au). page 19
Management recommendations The notes accompanying each map contain background information, the current condition of the river and management recommendations. These management recommendations can be used by a range of organisation as well as landholders. page 20
Index Map
Index Map THIS PAGE HAS BEEN LEFT BLANK INTENTIONALLY page 21 page 22
Reach 1 Leschenault Estuary to east of Australind Bypass. This reach is approximately 9km long. Much of the foreshore is crown reserve vested with the Shire of Harvey (right bank) or Shire of Dardanup (left bank, when facing downstream). DESCRIPTION FEATURE COMMENTS Landuse Urban development dominates both foreshores. It includes some of the older residential areas of Australind, Clifton Park and Eaton. New developments have Foreshore Management Plans and are responsible for the management of their foreshore area for 2 years, after which the foreshore is most likely to be vested with the Shire of Harvey or Shire of Dardanup. Land Tenure Lots 906, 250, 4717, 4847, 5536, 5579 and 5727 are crown reserves most of which are vested with the Shire of Dardanup. Lots 10, 5738, 301, 5188 and 5189 are crown reserves vested with the Shire of Harvey. The rest of the lots in the reach are privately owned. Fencing Little fencing is required as this is mainly an urban area. Only 2 lots have stock in this reach, and these are both fenced so the stock can not access the foreshore. Reach 1 CONDITION FEATURE COMMENTS Vegetation Salt Marsh Vegetation is evident near the Leschenault estuary and the saline floodplain north east of the Collie Bridge. This area is dominated by the low samphire Sarcocornia quinqueflora. Other species found in the saline regions include seablite (Suaedea australis), the shrubby glasswort (Halosarcia indica bidens) and shorerush (Juncus kraussii). Heading upstream forest vegetation begins to dominate with flooded gum (Eucalyptus rudis), swamp sheoak (Casuarina obesa), peppermint (Agonis flexuosa) and swamp paperbark (Melaleuca rhaphiophylla). Weeds Annual grasses dominte the understorey including; kikuyu, couch, pampass grass etc. Large patches of cottonbush, watsonia and blue lupin are also found along this reach. A small area of Lantana near boardwalk. Bank Stability & Artificial stabilisation structures are utilised from lot 5536 downstream to the river mouth. Erosion These structures include wooden boards to shore up the river banks near the estuary. Upstream of Collie Bridge rocks and concrete are used to stabilise the banks. Where these structures are present, rushes and sedges are scarce and erosion of the banks would definitely be active in these areas. However, further upstream beyond these structures, rushes and sedges are in healthy numbers and are successfully stabilising the riverbanks. Special Features, Much of the foreshore in this reach has potential for rehabilitation due to many reserves in Other Comments the area and the healthy overstorey. Restoration Sites The Clifton Park Management Plan was written with the community in 1993 and rehabilitation works have been occurring since on Reserve 5738. This site will undergo more works through funding from LCC in 2008, however it will require weed maintenance for the following three years and beyond if it is to be successful in the long term. Linking Communities Revegetation Project has been an ongoing project for the past 4 years. Please note “encourage” and “support” can mean to; provide financial support, education or page 23 page 24 technical advice, depending on the resources available.
Reach 1
Reach 2 Reach 2 extends from Australind Bypass to east of the South West Hwy (near Burekup). This reach is approximately 13km long. Private agricultural land abuts the river for the majority of this reach. DESCRIPTION FEATURE COMMENTS Landuse Agricultural land dominates both foreshores. Mainly beef, sheep and dairy industries are present, with one Winery and Orchard near Burekup. Land Tenure Lots 6213, 6211 and 31 are vested with the Shire of Harvey or a State Government body. The rest of the lots in the reach are privately owned. Fencing Lots 212, 333, 3315, 246, 314, 31, 7,8, 9, 10, 1,44 , 25, 26, 27, 28, 29, 30, 31, 2, 33,and 34 are fenced. However, in some cases cattle crash graze these areas. The remaining lots are either unfenced or fenced inadequately. For the majority of this reach cattle have access to the river banks. CONDITION FEATURE COMMENTS Reach 2 Vegetation The foreshore in this reach supports an overstorey consisting of flooded gum (Eucalyptus rudis), swamp sheoak (Casuarina obesa), peppermint (Agonis flexuosa)and swamp paperbark (Melaleuca rhaphiophylla). Native understorey is extremely sparse, with the majority of the understorey consisting of weeds. Rushes and Sedges are rare within this reach. Weeds Apple of sodum, blue lupin, watsonia, blackberry, bamboo and bridle creeper are of main concern in this reach. Apple of sodum is quite common stretching along much of this reach, where blackberry is only found in specific location. It should be noted that kikuyu and couch are a problem along this entire reach. Bank Stability & The majority of this reach is being impacted by some level of erosion. In many sections Erosion the soil is exposed, mainly due to livestock damage, and embankments are subsiding into the river. Rushes and sedges are found in very small numbers near Meadow Landings, but little to none elsewhere in the reach. Special Features, A community group has formed at Meadow Landings, LCC is assisting the group with Restoration Sites revegetation and weed control along the developments foreshore. Please note “encourage” and “support” can mean to; provide financial support, education or technical advice, depending on the resources available. page 27 page 28
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