Lake Wallace vegetation removal update

Published on 09 September 2022

West Wimmera Shire Council has successfully cut about eight-hectares of native vegetation at Lake Wallace.

The vegetation removal project was part of a trial to understand the operation of the weed cutting machine and the effect that weed cutting would have on nutrient levels in the water.

Council employed Aquatic Technologies to cut the weeds using an amphibious harvester.

Work started last week and took about eight days to complete.

Overall, about five per cent of the lake’s current surface was cleared, which included a rectangular area in the middle of the lake, and then five access channels.

Council Director Infrastructure Development and Works Ram Upadhyaya said the access channels were created to allow the cut vegetation to drift to the shoreline.

He said the channels would also give lake users access to the lake via multiple locations, including the jetty, caravan park and the boat ramp.

The amphibious harvester that was used to cut the weeds could crawl on the ground, as well as in the water, but did not have the capacity to collect the cut weeds.

“The weeds are currently floating in the water, and they will eventually drift to the shoreline with the wind,” Mr Upadhyaya said.

“The contractor recommended using the wind to push the weed to the shoreline as it was more efficient and economical.

“Using the harvester to push all the vegetation would take about two to three weeks of additional work.”

Council will undertake water testing at the lake in mid-October to understand the effect of weed cutting in the nutrient level of water.

Wimmera Catchment Management Authority (CMA) kindly committed to a contribution of $30,000 towards the weed cutting trial.