Lake Mulwala is on the rise over the next four weeks following the lowering of the lake over winter for successful weed control and completion of works around the lake foreshore.
Murray–Darling Basin Authority (MDBA) head of River Management, Andrew Reynolds, said locals and visitors to Lake Mulwala and Yarrawonga Weir might notice changes to water levels until early August.
"We are starting to re-fill Lake Mulwala to its normal operating level, which should happen by early August, in time for the new irrigation season," Mr Reynolds said.
"The drawdown was managed in a way that posed minimal risk of impacting on available water resources in the coming season.
"Stream flows from the Kiewa and Ovens rivers are being used to help re-fill the lake, along with water releases from Hume Dam. The actual completion of re-filling the lake is dependent on the amount of rain that falls in the catchments.
"It's been great to see the community interest generated by the lowering of the lake. We originally planned to lower it by 3.5 metres and then revised it down by another metre to ensure effective weed control.
"Lake Mulwala is important to the local community and we are very aware that any significant change in the lake level can have social and economic effects. However, this winter's lowering has been a drawcard for Mulwala.
"Locals and visitors have flocked to see what the lake looks like without water in it. We even had people asking not to re-fill the lake until after school holidays so that they could have time to visit with their families."
GMW Managing Director, Pat Lennon, said that the lake's winter drawdown was important because it allowed for effective control of the highly invasive aquatic weed Egeria densa.
"By lowering the lake we can target the aquatic weed which the community told us was impacting on the lakes' usage, making it harder to swim, fish, launch boats and water ski," Mr Lennon said.
"Throughout the drawdown we've seen the weed dry out and die off, which has been helped by the dry conditions of late. We also had half a dozen or so good frosts, which helps kill off the Egeria.
"As with previous winter drawdowns, this year appears to have been highly effective in controlling the waterweed, although we won't know the full extent until the next survey is undertaken in autumn.
"Along with reducing the weed's impact on recreational activities we used the opportunity to upgrade the retaining wall along the Yarrawonga foreshore and made some improvements to boat ramps."
Mr Lennon said he appreciated the community support for the weed removal process.
"We recognise the impact on recreation however management of weed infestation is important for lake health as well as managing infestations into GMW's channel systems."
Last year GMW and the MDBA released the Waterweed Wipeout app. The tool is designed to help the community better understand the management techniques used to control the invasive weed. Waterweed Wipeout is free and available from the App Store and Google Play for Apple and Android phones and tablet devices.
In accordance with the longstanding Murray–Darling Basin Agreement, River Murray operations assets are owned by a ‘Joint Venture' comprising of the states of New South Wales, Victoria and South Australia and the Australian Government. The MDBA is tasked to operate the River Murray system on behalf of the Joint Venture.
GMW is the state constructing authority responsible for managing and maintaining Lake Mulwala under the direction of the MDBA.
ENDS
For more information, contact the MDBA Media office at media@mdba.gov.au or
02 6279 0141 or Richard Bryce at GMW on (03) 5826 3470.
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