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2007 Audit of the Sydney Drinking Water Catchmentdownload 2007 Audit of the Sydney Drinking Water Catchment Report to the Minister for Climate Change, Environment and Water NSW Government 2007 Audit of the Sydney Drinking Water Catchment Report to the Minister for Climate Change, Environment and Water NSW Government Published by: Department of Environment and Climate Change NSW 59–61 Goulburn Street PO Box A290 Sydney South 1232 Phone: (02) 9995 5000 (switchboard) Phone: 131 555 (environment information and publications requests) Phone: 1300 361 967 (national parks information and publications requests) Fax: (02) 9995 5999 TTY: (02) 9211 4723 Email: [email protected] Website: www.environment.nsw.gov.au In April 2007 the Department of Environment and Conservation NSW became part of the Department of Environment and Climate Change NSW. This material may be reproduced in whole or in part, provided the meaning is unchanged and the source is acknowledged. ISBN 978 1 74122 674 4 DECC 2007/567 December 2007 Contents Executive Summary Recommendations Chapter 1 Introduction ................................................................................................................................... 1 1.1 The Sydney Water Catchment Management Act 1998 (the Act) .................................................. 1 1.2 Overview of the Audit ................................................................................................................... 1 1.3 The Sydney drinking water catchment (the Catchment)................................................................ 1 1.4 Multiple barrier approach to drinking water quality management................................................. 2 Chapter 2 Audit Methodology........................................................................................................................ 3 2.1 Overview........................................................................................................................................ 3 2.2 Arrangements for the Audit ........................................................................................................... 4 2.3 Conduct of the Audit...................................................................................................................... 5 Chapter 3 Raw Water Quality ....................................................................................................................... 9 Key Points......................................................................................................................................................9 Pressures in the Catchment........................................................................................................................10 3.1 Nutrient load ................................................................................................................................ 10 State of the Catchment ...............................................................................................................................21 3.2 Raw water quality requirements for water filtration plants ......................................................... 21 3.3 Algal blooms................................................................................................................................ 24 3.4 Pathogens..................................................................................................................................... 28 Actions and Response .................................................................................................................................31 Response to issue.................................................................................................................................. 31 Gaps in the response............................................................................................................................. 38 Chapter 4 Managing Water Resources ....................................................................................................... 39 Key Points....................................................................................................................................................39 Pressures in the Catchment........................................................................................................................40 4.1 Surface water extraction .............................................................................................................. 40 4.2 Groundwater extraction ............................................................................................................... 43 4.3 Water for the environment ........................................................................................................... 46 Actions and Response .................................................................................................................................51 Response to issue.................................................................................................................................. 51 Gaps in response................................................................................................................................... 57 Chapter 5 Land Condition............................................................................................................................ 58 Key Points....................................................................................................................................................58 Pressures in the Catchment........................................................................................................................59 5.1 Changes in land use ..................................................................................................................... 59 5.2 Sites of pollution and potential contamination ............................................................................ 63 State of the Catchment ...............................................................................................................................69 5.3 Soil erosion .................................................................................................................................. 69 5.4 Salinity......................................................................................................................................... 72 Actions and Response .................................................................................................................................73 Response to issue.................................................................................................................................. 73 Gaps in the response............................................................................................................................. 81 Chapter 6 Ecosystem Health ........................................................................................................................ 82 Key Points....................................................................................................................................................82 Pressures in the Catchment........................................................................................................................83 State of the Catchment ...............................................................................................................................84 6.1 Ecosystem water quality .............................................................................................................. 84 6.2 Macroinvertebrates ...................................................................................................................... 88 6.3 Fish............................................................................................................................................... 91 6.4 Riparian vegetation ...................................................................................................................... 97 6.5 Native vegetation ......................................................................................................................... 99 Actions and Response ...............................................................................................................................101 Response to issue................................................................................................................................ 101 Gaps in the response........................................................................................................................... 109 Chapter 7 State of the Sub-catchments ..................................................................................................... 110 Chapter 8 Management Overview ............................................................................................................. 121 Chapter 9 Audit Recommendations........................................................................................................... 126 9.1 Overview.................................................................................................................................... 126 9.2 Review of the 2005 Recommendations ..................................................................................... 126 9.3 Compilation of the 2007 Audit Recommendations.................................................................... 132 Acronyms ....................................................................................................................................................
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