2002-2003

Executive Summary

TAMS manages a water monitoring and assessment program for the ACT that includes water quality, streamflow monitoring, and biological monitoring. This information is used to determine whether management strategies used to achieve or maintain the aquatic values set for ACT waters are appropriate.

The report is intended to provide the community with information regarding the state of water resources in the ACT. The assessment approach adopted is designed to move towards a more holistic ecosystem health monitoring system as prescribed by the Murray-Darling Basin Commission’s Sustainable Rivers Audit. It uses biological data to ascertain ecosystem diversity, water quality data to determine trends that may be present and compares these results with the designated environmental and use values and standards set in the Territory Plan and Environment Protection Act 1997 and its regulations. Streamflow monitoring is used to gauge the impact of removing water from the environment for other uses.

Water quality is monitored in the major urban lakes (with the exception of Lake Burley Griffin, a Commonwealth responsibility) and Burrinjuck Reservoir, which is immediately downstream of the ACT. The major rivers and some urban streams are also monitored. River flow is measured at a number of sites throughout the ACT.

The report uses the biological information to report the biodiversity in the rivers. The sampling data is analysed, determining any trends that may be present for the period 1992-2003. The individual data points and median values for the year are considered with reference made to the standards set out in the Territory Plan and Environment Protection Act 1997.

Rainfall and streamflow for the 2002-2003 reporting period was well below the long-term average. This reporting year has seen environmental conditions in water bodies deteriorate due to the negative effects caused by very low rainfall and flows during, as well as leading up to the reporting period. This is despite the relatively good long term condition, and good compliance with standards. This is particularly noticeable in the biological data. The impacts on water quality in the urban areas that derive from land development with urban run-off carrying suspended sediment and nutrients have been exacerbated, and further impact could be predicted to occur in the next reporting period after significant rain events have washed accumulated pollutants into the water bodies.

Toward the end of the reporting year, major bushfires occurred in the Canberra region, affecting a large proportion of the ACT’s land area and catchments. Biological monitoring in Autumn 2003 showed significant levels of impairment, attributable in part to the bushfires. The physio-chemical data was yet to show significant effects expected. This is primarily due to no high flow sampling being conducted after the fires, as the only significant rain event, did not convert to adequate flows at preselected sampling sites. Subsequent annual reports should give a better picture of the overall condition of the ACT’s water bodies after the fires.

Despite drought and fire effect, Canberra’s lakes, Lake Ginninderra and Lake Tuggeranong, have fair water quality with a discernible improvement in water quality conditions through the length of both lakes, and thus in the water that flows out into our creeks and rivers. Point Hut Pond and Gungahlin Pond have comparatively poor water quality with elevated levels of turbidity and suspended solids. Runoff from residential development in the Point Hut catchment is the most probable cause. Lake Ginninderra and Gungahlin Pond have high pH readings, attributable to drought effect.

The Water Resources Act 1998 came into full effect in December 1999 and requires assessment of river flows, and licensing of water abstractions. Since that time considerable progress has been made implementing the provisions of the Act. Most notably, all water use, except stock and domestic use from surface water is now required to be licensed. This includes all use from bores. The pressure on these resources has increased during the reporting period, with an increase in the application to construct bores and an increase in applications for licences to take water, particularly in urban areas.

Report

The full water report is available for download below: