The Murray-Darling Basin Authority (MDBA) has announced it will begin lowering the level of Lake Mulwala in early May.

Lowering the lake is said to provide the best means of controlling the highly invasive waterweed Egeria densa, and will also allow other maintenance work to be completed.

“The last time the lake was lowered was in 2018 and since then the weed has become dense so it's important that we act this winter to improve the condition of the lake to support the community, businesses and the health of the lake itself,” says MDBA executive director, Dr Andrew Kremor.

“In order to kill the waterweed, we need to expose it to the air and winter frosts which we will do by lowering the lake by 5 metres below operating level and holding that level for about a month.

“We expect to bring the lake back to its regular operating levels by early August.”

The authorities say they consulted with the local angling and water-ski clubs, irrigators, local councils, the Yorta Yorta Traditional Owners, tourism and hospitality operators, NSW and Victorian government agencies and others to confirm the best date.

The lake-lowering project is being undertaken in partnership with Goulburn-Murray Water (GMW), whose Water Storage Services General Manager Martina Cusack says will allow for a range of works to be conducted.

“We plan to use this opportunity to carry out maintenance under and around the bridge including pylon inspection, as well as lake retaining wall works and erosion repairs,” she said.

“It also offers an excellent opportunity for residents around the lake to carry out inspections and maintenance on their own infrastructure, such as jetties, boat ramps, retaining walls and pipe intakes.

“We remind lake users to consider adjusting their activities for changed water levels in late autumn and winter,” Ms Cusack said.