An innovative water treatment trial is due to begin in Busselton’s Lower Vasse River in November as part of the State Government’s Revitalising Geographe Waterways program.
The Department of Water and Environmental Regulation will be leading a Phoslock application in the river with the aim to reduce summer algal blooms.
Phoslock is a commercially available clay product that effectively removes dissolved phosphorus from water so that it is unavailable for algal growth. It has been used successfully in waterways worldwide and is tested and safe to use in natural waters.
The product application will occur between the Causeway Road bridge and the Butter Factory in Busselton. The first stage of the trial will involve installing a floating curtain at Causeway Road bridge to minimise water flowing into the trial site.
This will be followed by two to three applications of Phoslock between November and January which will be applied as a slurry with a spray boom from a moving pontoon.
Water quality monitoring will be undertaken in the river over summer months to assess the effectiveness of the product.
“The Busselton community are very concerned about the health of the Lower Vasse River and it is important to identify scientifically rigorous management options to improve water quality,” DWER South West Regional Manager Kath Lynch said.
“If this trial is shown to be effective this summer, it may be an option for long-term treatment of algal blooms in the river.”
The Lower Vasse River flows through the centre of Busselton and is highly valued by the local community. The river can suffer severe algal blooms during the warmer month caused by excess nutrients entering the river from the catchment.
The Phoslock application will complement other initiatives to improve water quality in the Lower Vasse River, including actions to reduce nutrients leaving urban and rural catchments and sediment removal in the river undertaken over the last two years by the City of Busselton.
A successful small-scale Phoslock trial was undertaken in the Lower Vasse River in the early 2000s and scientists hope that this broadscale application will help to determine if the product is a viable option to reduce summer algal blooms on an annual basis.
“This project complements the suite of Vasse Taskforce projects that are working to reduce nutrients from the catchment,” Dr Lynch said.
“Improving water quality in the Lower Vasse River is a high priority for the Vasse Taskforce and we are looking forward to the results of this innovative new trial”.
This project is part of Healthy Estuaries WA and Revitalising Geographe Waterways. These State Government initiatives aim to support the long-term health of our south-west estuaries.