Revitalising Geographe Waterways program | Local product protecting waterways

Water Minister Dave Kelly, City of Busselton mayor Grant Henley, Iluka Resources project manager Mike Harwood and Department of Water senior natural resources manager Kirrily Hastings. Photo by Emma Kirk.
Water Minister Dave Kelly, City of Busselton mayor Grant Henley, Iluka Resources project manager Mike Harwood and Department of Water senior natural resources manager Kirrily Hastings. Photo by Emma Kirk.

A trial is underway in Vasse looking at how a locally made soil additive could prevent fertilisers from polluting waterways, causing algal blooms and fish kills in the region. 

The program is being supported by the state government led by the Department of Water and Environmental Regulation through the Revitalising Geographe Waterways program.

Water Minister Dave Kelly visited the trial site at the Vasse Sporting Complex Oval last week where the soil additive was applied under the recently expanded playing areas.

The soil additive, ‘Iron Man Gypsum’ is a mineral processing by-product developed by Iluka Resources, which works to bind phosphorus in soil while allowing plants access to the nutrient.

It is being trialled for its effectiveness in reducing leaching of fertilisers from redeveloped farmland, as well as its potential for reducing fertiliser loss from turf in the sports ground.

Monitoring sites have been set up to measure the success of the additive in reducing nutrients leaching from the soil of the newly constructed oval.

The trial is a partnership between the City of Busselton, the Department of Water and Environmental Regulation and Iluka Resources Ltd.

Water Minister Dave Kelly said this trial was just one example of the scientific work the Department of Water and Environmental Regulation is carrying out to ensure the protection of our local waterways. 

“Preventing nutrient run-off from historically over fertilised farm land is important to improve the health of waterways in the South West,” he said.

“We know that approximately half of the land cleared for agriculture in the Geographe catchment is on soils that tend to be very poor at retaining phosphorus.

“Soil additives that bind phosphorus help to ensure fertiliser stays in the soil longer to benefit plant growth and limit the nutrients that enter local waterways and cause damaging and unsightly algal blooms.

“Scientific modelling shows that in some areas in Vasse Geographe, the widespread use of soil additives has the potential to reduce phosphorus loads by over 30 per cent.”