Deforestation and urbanisation have created major water quality problems in Australia’s largest coastal lake on the Central Coast of NSW. Stormwater related problems in Lake Macquarie include elevated nutrient and bacterial pollution and increased sedimentation associated with catchment erosion.
With $448,000 funding from the Commonwealth’s Urban Stormwater Initiative, a consortium led by Lake Macquarie City Council is tackling stormwater head on. Partners include the State Government, The Office of the Lake Macquarie and Catchment Coordinator, major industry, Landcare and urban residents.
An integrated approach to managing urban stormwater employing a range of low cost treatment devices based on soft engineering and current understanding of natural processes is being used.
At the project launch, Mayor, Councillor John Kilpatrick, congratulated the Commonwealth on the initiative, pointing out that, the project will build upon a valuable partnership between all tiers of government and the residents of Lake Macquarie, who have been contributing through the three year Lake Levy.
Lake Macquarie City Council is aware that there is no quick fix or ‘one size fit all’ for stormwater treatment. It has developed three types of Stormwater Quality Improvement Devices (SQIDs) that are tailored to site catchment characteristics and surrounding natural wetland conditions.
With over 400 drains discharging into the Lake, micro treatment approaches are preferred to expensive engineered solutions.
The new SQIDs approach eliminates the need to construct large wetlands or expensive prefabricated Gross Pollutant Traps. Tailored micro technologies including mini wetlands and riparian filter strips will remove up to 98% of gross pollutants, 90% of coarse sediments, 60% of fine sediments and 40% of nutrients. The first SQID’s will be tested hotspots in the catchments of the Swansea Flats, Cockle Creek and Edmunds Bay.
Lake Macquarie Catchment Coordinator, Jeff Jansson, said that it is important to seek community cooperation in preventing pet faeces, garden wastes and soil being washed into stormwater drains.
“I’ve come across people that will complain about the condition of the foreshore and yet tip grass clippings over the back fence into the drain,” he said.
Lake Macquarie City Council, with the support of the NSW Stormwater Trust, has initiated an ‘Adopt a SQID’ program that involves community monitoring, reporting and outreach education on the performance of SQIDs. Construction in each priority catchment will be complemented by riparian zone rehabilitation, source control and educational activities and monitoring.
This project offers an opportunity for value adding to existing works and to showcase cost effective techniques to other regions.
For further information contact Neale Farmer, telephone (02) 4921 0365, or email nfarmer@lakemac.nsw.gov.au.
