Innovative water treatment trial shows early promise

Department of Water and Environmental Regulation scientists apply clay solution to the immersed tank.

Initial stages of a trial aimed at controlling algal growth in the Lower Vasse River has demonstrated improved visual amenity and reduced phosphorus build-up associated with algal blooms.

High nutrient concentrations and low flows in the river over summer can lead to blue-green algal blooms and nuisance odours.

Fifteen tanks were immersed in the river near the Lower Vasse traffic bridge by Department of Water and Environmental Regulation scientists in November 2016. An innovative new clay product was applied to the tanks at different doses. The clay strips phosphorous from the water and prevents phosphorous release from the sediments.

“We have been really pleased with the visual improvement in water quality in the tanks with the clay compared to those with no clay,” said Dr Svenja Tulipani, lead scientist on the trial.

“We are now looking closely at the water quality data collected over the trial to assess if we extend the trial over larger areas of the river next summer.”

The trial is part of a series of experiments to explore unique ways to improve soil condition and reduce nutrients entering waterways from urban and rural land uses.

At a recent forum held in Busselton, the Department of Water and Environmental Regulation shared this information with interested community members.

Organised by local catchment group GeoCatch, the forum aimed to build a better understanding of current waterway and estuary health, sharing this information with communities to guide future management and planning.

This project is part of Revitalising Geographe Waterways and the Regional Estuaries Initiative.