“What little vegetation that grew back after the drought was scoured away during the floods,” North Cental CMA’s Darren White said.
“While the vegetation is recovering well in places, it hasn’t got back to the levels it was before the drought.
“With irrigation water deliveries at certain times of the year, there hasn’t been an opportunity to focus on rebuilding those sections of the river, but there is now.”
Mr White said the recent wet weather had caused irrigation demand to drop off at the right time of the year, creating a rare opportunity for action.
“We have a unique opportunity here, given the Campaspe is a highly regulated river, to make some big inroads into re-establishing that vegetation,” he said.
“Without irrigation water, we can keep water flows at about 20Ml a day from Eppalock Reservoir to Rochester, to expose those lower benches and banks.”
Mr White said exposure to air and sunlight at this time of year may help the vegetation re-establish itself on those key parts of the river.
“The low flow aims to replicate the natural drawdown of river levels at the end of summer that is important for plant recruitment but no longer occur due to river regulation.
“Then we’ll ramp the flows up slowly to 50Ml a day, giving any vegetation that has established the opportunity to adapt to slightly deeper water.
“Healthy vegetation means better filtration and more waterbugs, which means more food for fish and platypus.
“We’re working closely with the Arthur Rylah Institute on this plan, and if successful it will help inform river management across Victoria.”
The flow alterations started on May 9.
“From Eppalock to Rochester the water will look a bit low for a couple of weeks, but from Rochester to Echuca there will be no change,” Mr White said.
“Water will remain high in existing pools, and the lower flow will still connect them, so it’s unlikely there’ll be any negative impact on fish or platypus.
“This event shows improving the health of a river is more than just about adding water for the environment.”
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