We monitored water quality as part of our Beach Report and Yarra Watch programs. The last season ran from 1 December 2020 until 8 March 2021. This is when people use Port Phillip Bay and the Yarra River the most for recreation.
Both programs monitor for microbial water quality. Read more in Beach Report and Yarra Watch results 2020-21 (publication 1987).
Microbial sampling results
During the 2020-21 season, our sampling results showed that water quality met standards:
- 91 per cent of samples taken for Beach Report
- 66 per cent of samples taken for Yarra Watch.
State Environment Protection Policy (Waters) was the policy that set the water quality standards for recreational use. We issue swim advisories when weekly sampling results don’t meet these water quality standards. We issued three advisories for Beach Report and one advisory for Yarra Watch in the 2020-2021 season.
We predict water quality using weather data, mostly rainfall. During the 2020-2021 Beach Report season, our forecasts:
- predicted Good water quality for 69 per cent forecasts issued
- were accurate 90 per cent of the time.
The number of Good water quality forecasts we issued was greater than the previous year. This was mostly due to a decrease in rainfall over the summer period.
During the 2020-2021 Yarra Watch season, our forecasts:
- predicted Poor water quality for 82 per cent of the forecasts issued
- were accurate 52 per cent of the time.
We are working to improve our forecasting model to continue to provide appropriate public health information.
Reviewed 20 August 2021