Flooding for Life
Above-average rainfall and flooding in Victoria’s High Country is providing an unexpected boost to Gunbower Forest.
Rainfall as much as 200 per cent above average in the Goulburn, Kiewa and Ovens river catchments in July has resulted in more water than expected entering the Murray River downstream of Lake Hume.
These extra, or unregulated, flows cannot be captured in Victorian storages. Creeks that feed Gunbower Forest from the Murray River have already started flowing, and inflows are expected to increase during August.
Over-bank flooding is expected on Gunbower Island in the coming weeks.
North Central Catchment Management Authority (CMA) Project Manager Anna Parker said the flows will present the forest with a wonderful opportunity.
“Water in the forest at this time of year brings natural cues into play. It will give native fish the opportunity to move onto the floodplain to feed and breed. It will also provide habitat for waterbirds and possibly trigger a waterbird breeding event,” she said.
“The flows over the next week or so are expected to fill the permanent and semi-permanent wetlands of the forest before pushing out into the red gum areas.
“This will be a good start because without river regulation and water being diverted to reservoirs, the amount of rain we have had across the Murray-Darling Basin this winter would naturally have led to significant flooding in the forest in June.”
Ms Parker said if the extra Murray flows continue to increase, as expected, it is likely more water will be available to use in the forest.
“Over the next few months we will continually work with our ecologists, environmental water holders, Goulburn Murray Water and Gunbower land managers to monitor the flooding,” she said.
“Depending on how the flooding progresses we may look to piggy back environmental water at the end of the natural flooding to extend the duration of the event to be in line of what would have occurred outside river regulation.
“This will help ensure any bird breeding event can be sustained and will allow native fish that have entered or been born on the floodplain to swim back to the river.
“It will also help mitigate toxic blackwater risk for future flows.
“This extra water is also likely to benefit the Hattah Lakes and Barmah Forest, and is an unexpected benefit to the long-term health of the Murray River floodplain.
“Our planning each year looks at all climatic scenarios, meaning we have provisions in place to take advantage of these opportunities when they arise.
The Gunbower Flooding for Life project is delivered by the North Central CMA in partnership with Goulburn–Murray Water, Department of Environment, Land, Water and Planning (DELWP), Parks Victoria and the Victorian Environmental Water Holder. It is part of The Living Murray program, a joint initiative of the New South Wales, Victorian, South Australian, Australian Capital Territory and the Commonwealth governments, coordinated by the Murray–Darling Basin Authority.