The screens — locally designed and manufactured by Cohuna’s AWMA Water Control Solutions — were installed in 2018 in front of the Cohuna Number 3 Channel regulator in the centre of the town.
They have been fully functional for more than 90 per cent of that time, saving a countless number of native fish from being lost to the system.
“Studies have shown the screens have stopped 98 per cent of fingerlings from travelling down to the channel, which is an amazing result,” North Central Catchment Management Authority project manager Peter Rose said.
“It’s important Murray cod, golden perch and silver perch stay in the creek and river system to maintain local populations.”
The screens are expected to be back online by mid-October after minor repairs.
Dr Rose said small operational changes may need to be made in the future to cope with increased vegetation in the creek.
“The increase in nutrients in waterways in the region following the 2022 floods has resulted in rapid growth of aquatic plants such as hornwort,” he said.
“When high vegetation loads are dislodged or fragmented by strong flows or increased boating activity, it flows down the creek and can inundate the weed boom located in front of the screens and accumulate at the stop boards and around the screen.
“That will mean from time to time we will remove the stop boards and let the vegetation flow through but overall, these screens will continue to provide a significant benefit to the local native fish population.
“In the meantime, we’ll continue to investigate ways to adjust the weed boom to cope with the increased vegetation.”