Located on the southern side of Mosman in Port Jackson, Little Sirius Cove was named after the ‘Sirius’, a First Fleet supply ship, which was careened in nearby Mosman Bay after circumnavigating the world in 1789. Like most other areas in Mosman, the Little Sirius Cove catchment is primarily residential. Pollutants in stormwater flowing from the catchment, including litter, organic matter, sediments, nutrients and chemicals, have affected water quality in the Cove.
This $615,000 project received funding from Mosman’s CEC and the State Government’s Stormwater Trust. It involved the installation of Stormwater Quality Improvement Devices (SQIDs), education campaigns, and stormwater quality monitoring and analysis. An analysis of the three SQIDs installed and visual inspection of the catchment area revealed that a majority of the gross pollutant load comprised leaves and organic vegetation.
This, and the knowledge that up to 60 per cent of households in Mosman use a commercial gardening service lent itself to the implementation of education and awareness campaigns for commercial gardeners working within the Sirius Cove Catchment.
The success of the gardeners education campaign in the Little Sirius Cove catchment was an important reason for the continuation of the campaign in the Lawry Plunkett Reserve Environment and Heritage Project. The environmental monitoring component of the project monitored one of the installed SQIDs over a 12 week period from 25 May 2002 to 16 August 2002 and encompassed the sampling of four storm events. Water samples were collected both upstream and downstream of the SQID and analysed using 22 water quality parameters. The results found that the pollutant concentrations for all but four of the water quality parameters decreased downstream of the device, improving downstream water quality. The monitoring of such stormwater components is an important learning task and helps to improve the outcomes of future projects.
