Waterways and wetlands Perth-Peel regional water plan background paper Looking after all our water needs Department of Water September 2009 Department of Water 168 St Georges Terrace Perth Western Australia 6000 Telephone +61 8 6364 7600 Facsimile +61 8 6364 7601 www.water.wa.gov.au © Government of Western Australia 2009 September 2009 This work is copyright. You may download, display, print and reproduce this material in unaltered form only (retaining this notice) for your personal, non-commercial use or use within your organisation. Apart from any use as permitted under the Copyright Act 1968, all other rights are reserved. Requests and inquiries concerning reproduction and rights should be addressed to the Department of Water. 978-1-921637-88-9 (online) Contents Summary .................................................................................................................... iv 1 Introduction..............................................................................................................1 1.1 Waterway and wetland values ..........................................................................................1 1.2 Management responsibilities ............................................................................................2 1.3 Values under pressure......................................................................................................2 2 Moore-Hill river basin ..............................................................................................5 3 Swan coastal basin .................................................................................................6 3.1 Swan-Canning conditions .................................................................................................6 1.4 Gnangara and Jandakot mounds .....................................................................................8 1.5 Salinity ............................................................................................................................ 10 2 Murray River basin ................................................................................................12 2.1 Values and conditions..................................................................................................... 12 2.2 Water quality improvement plan ..................................................................................... 13 2.3 Drainage and stormwater planning................................................................................. 15 2.4 Peel-Harvey system governance.................................................................................... 16 3 Waterways and wetlands as ecological linkages...................................................17 4 Climate change .....................................................................................................21 4.1 Potential impacts ............................................................................................................ 21 4.2 Ecological water needs................................................................................................... 22 Appendices................................................................................................................23 Appendix 1 — Existing programs............................................................................................. 23 Appendix B — significant waterways and wetlands................................................................. 25 Shortened forms ........................................................................................................28 References ................................................................................................................30 Department of Water iii Summary The Perth-Peel regional water plan (PPRWP) will provide strategic directions for sustainable water management in the region to the year 20301. Figure 1 displays the Perth-Peel region’s boundaries including its three subregions: Gingin, Perth and Peel. Figure 1 Perth-Peel regional water plan boundary This background paper provides an overview of the condition of waterways in the Perth-Peel region, the pressures they are experiencing, key management programs and additional needs. It is one of four background papers prepared in support of the Perth-Peel strategic directions discussion paper released by the Department of Water in March 2009. The four Department of Water background papers are: 1 Water efficiency, recycling and alternative water supplies 2 Waterways and wetlands 3 Climate change, water demand and water availability scenarios to 2030 4 Land and water planning 1 Water resources in this context do not include marine waters. ____________________________________________________________________________________________________________ iv Department of Water 1 Introduction 1.1 Waterway and wetland values A waterway can be a creek, brook, river or stream, and include a lake, estuary or inlet at its base. Waterways also include floodplains and wetland systems that overflow into rivers, as well as any lakes or swamps that are filled (mainly) by streams rather than shallow groundwater. Wetlands not only include lakes with open water but areas of seasonally, intermittently or permanently waterlogged soil. Approximately 25 per cent of the Swan coastal plain between Moore River and Mandurah is classified as wetland (WRC 2001). The region’s waterways and wetlands are valuable natural assets because they provide habitat for aquatic and terrestrial flora and fauna, and support biodiversity and threatened species. They drain land, transport and store water, and carry flood waters. Wetlands influence the water quality of rivers and streams by removing pollutants such as sediments, nutrients, organic and inorganic matter and some pathogens. Many of the region’s waterways and wetlands are recognised at regional, state and national levels for their ecological values, such as providing breeding grounds for migratory waterbirds. The Thomsons and Forrestdale lakes and the Peel–Yalgorup system are listed for protection under the Ramsar Convention on Wetlands of International Importance. The region’s waterways are also valuable tourism assets and prized recreational areas. They provide a source of water for drinking, fisheries, agriculture, mining and other industries. A recent study estimated the private-sector value attached to the Peel Inlet and Harvey Estuary at a net present value of $5200–$19 930 million (ECS 2008). Waterways and wetlands support many in situ social values including: • recreation • cultural and heritage (Aboriginal and non-Aboriginal) • landscape and aesthetic • educational and scientific. Waterways and wetlands are important components of the state’s cultural landscapes2. George Seddon popularised the concept of ‘sense of place’ in his discourse about the Swan coastal plain (Seddon 1971). Natural landscapes and places are locations filled with history, memories, and emotional and symbolic meanings (Williams & Vaske 2003). The region’s water landscapes play an important role in the customs and spiritual beliefs of the Nyungar people. The landscapes are of cultural value through a spiritual or heritage connection stemming from knowledge of their ancestors using and living in these places (Estill & Associates 2005). Some waterways, such as the Swan River and the Peel-Harvey estuarine system, have iconic status as ‘special places’ within the region. The planned creation of the Swan Canning Riverpark under the new Swan and Canning Rivers Management Act 2006 (WA) and the Peel Regional Park (Peel Inlet, Harvey Estuary and the lower parts of the Murray, Serpentine and Harvey rivers) recognises how highly the community values these waterways and their contribution to the region’s landscape. 2 The concept of cultural landscapes integrates, for any one place, aspects of natural, Indigenous and historic, aesthetic, scientific and social heritage values (Jane Lennon & Associates 2001). Department of Water 1 1.2 Management responsibilities The Department of Water is the lead organisation ensuring the management of waterways through its Waterways Program. The Department of Environment and Conservation (DEC) is directly responsible for the management of wetlands. However, the Department of Water must also consider wetlands management as part of its responsibilities for the maintenance of aquatic ecosystems and water-dependent terrestrial ecosystems. The Swan River Trust (SRT) is responsible for management programs and projects to address threats to the ecological health and community benefit of the Swan-Canning river system. The Environmental Protection Authority (EPA) assesses proposed actions that may have a significant environmental impact on wetlands and waterways. Some of the proposals it has assessed in relation to wetlands and waterways include estuarine marinas and urban development projects in catchments on the Swan coastal plain. Environmental protection policies of relevance to particular waterways and waterway catchments in the Perth-Peel region are: • Environmental Protection (Swan and Canning Rivers) Policy 1998 • Environmental Protection (Peel Inlet–Harvey Estuary) Policy 1992 • Environmental Protection (Swan Coastal Plain Lakes) Policy 1992 • Draft Environmental Protection (Swan Coastal Plain Wetlands) Policy 2004 Natural resource management (NRM) councils also play a significant role in waterways and wetland management. The Perth-Peel region falls within the areas of three catchment councils: the