Weed harvester at work

Fraser Coast Regional Council can now put its Aquatic Plant Management Policy to work with the launch of a floating weed harvester.

Councillor Robert Garland said buying the machine would allow Council to undertake more regular weed control.

“Council has in the past used contractors to undertake weed harvesting on our stormwater detention basins.

“With our own machine we will be able to stay on top of the weeds.”

Council launched the weed harvester for its first outing on Condor Lakes, and it will move on to others such as those near the Yarilee State School, Ululah Lagoon and Pricket Aquatic Centre in Maryborough.

Infrastructure Planning and Delivery Portfolio Councillor Trevor McDonald said they anticipated the harvester will be used mostly between March and April and August and September.

Cr McDonald said the harvester was only one part of Council’s strategy to control water weeds on stormwater detention basins.

“There has to be some weed growth on the basins to ensure they are healthy, remove nutrients from the water and trap sediment so it will not reach the ocean.

“What we don’t want however is blooms of weeds which can cause fish kills and odour problems.”

Council’s long-term management plan includes, where possible, planting vegetation around basins to soak up nutrients. It is also trialling the use of solar-powered pumps to improve water quality.

A solar-powered pump capable of circulating 19,000 litres of water per minute was installed in the deepest section of the detention basin near the University of Southern Queensland campus.

The pump creates a current which circulates water around the basin improving the amount of dissolved oxygen in the water, especially at lower levels.

The oxygen-rich water and current help nutrient-rich material settle at the bottom of the basin, which in turn cuts floating weed growth and blue-green algae, which usually bloom in nutrient rich water.

Instead, more edible algae grow, to feed fish and other aquatic animals in the basin.

The improved water quality boosts fish numbers, which in turn helps keep weed and algae growth under control.