The 2010 audit of the Sydney Drinking Water Catchment was prepared in accordance with Sydney Water Catchment Management Act 1998 (s.42).
This audit provides information on the indicators used to assess the pressures on and changes in the Sydney Drinking Water Catchment during the period 1 July 2007 to 30 June 2010.
Where possible, the audit identified trends in selected indicators. The catchment was split into 27 subcatchments and 18 indicators grouped into 4 broad themes (land use and human settlements, biodiversity and habitats, water availability, water quality) were assessed.Report findings included:
- dam and weir infrastructure had changed to enable access to deeper water and the passage of variable environmental flows
- fish passage was restored through construction and operation of fishways in the Nepean Weirs Project and the fish ‘lift’ on Tallowa Dam
- reporting for the Kangaloon borefield project was completed, including dissemination of about 60 technical, scientific and environmental investigations
- the Draft Water Sharing Plan for the Greater Metropolitan Region Unregulated River Water Sources (NOW 2010a) was exhibited
- the Draft Groundwater Sharing Plan for the Hawkesbury–Nepean Catchment Sources (NOW 2010b) was developed
- catchment management had improved through on-ground erosion control, riparian zone rehabilitation, native vegetation rehabilitation and replanting, and weed control work
- community and landholders had been involved in natural resource management
- monitoring and reporting had continued
- a ‘blowdown’ by Delta Electricity and mine water discharges in the Upper Coxs River sub-catchment had high concentrations of salt and heavy metals
- longwall mining impacts on rivers, streams and swamps and the expansion of coal mining under the Metropolitan and Woronora Special Areas
- blue–green algal blooms had occurred in Warragamba Dam throughout most of 2007
- water transfers had been conducted from the Shoalhaven River catchment
- continued high demand to develop land throughout the catchment, particularly in existing urban areas and in the Sydney to Canberra corridor.
Information from this audit, and past audits, can be used to guide land managers and the community to make decisions about the management of the catchment.
Appendices to this report have been compiled in Audit of the Sydney Drinking Water Catchment Volume 2.
Other audit reports available on this website for this catchment include: