The Campaspe River is bouncing back better after the 2022 floods than it did in 2011, boosted by more than a decade of environmental flows and riverbank revegetation and protection.
That’s the message from North Central Catchment Management Authority.
The one-in-200-year 2011 floods decimated the Campaspe downstream of Lake Eppalock, and with the 2022 floods measured as about a one-in-500-year event, the impact was expected to be worse.
However, North Central CMA says the latest preliminary monitoring results have shown the riverbanks are healthier than after the 2011 floods, and key fish populations have bounced back almost immediately.
The results come on the back of 12 years of the Caring for the Campaspe fencing and revegetation project, and carefully managed water for environment flows.
“The latest fish surveys by the Arthur Rylah Institute have shown similar numbers of golden perch to what were found in the two years before the 2022 floods,” North Central CMA Environmental Flows Program manager Darren White said.
“Murray cod were also captured in all three reaches of the river, ranging in size from 57mm to 802mm, including multiple young-of-year fish. That all points to a resilient fish population and a recovering river,” he said.
“The fish numbers are proof the river is bouncing back. They are at the top of the food chain in the river channel, so if they are doing well, everything else that’s in there is doing well.
“A key aim of environmental flows is to build resilience to protect the river from regulation and climate change, so it’s pleasing to see that happening.”
The surveys were carried out as part of VEFMAP (Victorian Environmental Flows Monitoring and Assessment Program).
The Caring for Campaspe Project has worked with the community since the 2011 floods to protect and restore the riverbanks.
“We’ve constructed more than 100km of fencing, controlled 668ha of weeds, and revegetated 576ha of the banks, and it has paid off,” North Central CMA Environmental Assets Program manager Nicole Bullen said.
“After the 2022 floods, once we were able to access the sites again, we found the riverbanks intact — the revegetation work had done its job in holding the bank together.
“This is a remarkable achievement only made possible by leveraging the passion and commitment to river health of Campaspe landholders and community.”
Maximising the recovery work will continue in September, with a planned spring fresh to travel down the Campaspe from Lake Eppalock.
“Up to 1600 megalitres a day for three days will flow down the river to wet the banks in preparation for warmer weather,” Mr White said.
“The flow will also help fish and platypuses move up and down the river in search of mates and flush any leaf litter through the system to help protect water quality in summer.”