Rivers set to benefit from Autumn flows

More about water for the environment

Find out more about water for the environment, including more details about these current releases.

Water will be released from water storages in the Macalister and Thomson rivers to help support the spawning of migratory fish and flush the estuaries in our river systems.

West Gippsland Catchment Management Authority’s, Environmental Water Resource Officer, Dr Steph Suter said after recent bushfires in other parts of Gippsland and dry conditions in 2019, this autumn’s freshes were more important than ever.

“In the Macalister and Thomson rivers, we’re releasing a ‘fresh’ of water, which means a small pulse of water released over several days, creating a peak in river flows that will help trigger the downstream migration and spawning of Australian grayling,” said Dr Suter.

“This will be followed by a baseflow in both rivers. The purpose of the baseflow following the freshes is to provide what we call ‘longitudinal connectivity’ which essentially means providing enough depth in the river to allow fish and other animals to move up and down the river.”

In the Latrobe River, two ‘freshes’ will be released which will provide beneficial flows in the river and down to the estuary and wetlands, timed either side of the Macalister and Thomson river flows.

“We carefully time our releases of environmental water to try to get great results for plants, animals and fish,” continued Dr Suter.

“Last year, our water release encouraged the rare and endangered Australasian bittern to visit Sale Common. This was the first confirmed siting of a bittern in almost 30 years.

“The flows in all three major rivers will also coincide to help flush salt and improve water quality in the lower Latrobe estuary and wetlands.”

Dr Suter explained that people may notice a slight increase in river height during the peak flow periods.

“We’re very careful not to cause flooding with our water releases, but people will notice that the rivers are slightly higher.”

Many rivers have been modified to provide water for towns, industry and food production. This means that about half of the natural flow in the rivers is removed each year. As a result, it is difficult for these rivers to support the animals and plants that depend on them.

Water is set aside in the Blue Rock Reservoir, Thomson Reservoir and Lake Glenmaggie to be used to support the animals and plants of our rivers to live, feed and breed and to improve the resilience of these waterways.

For more information about water for the environment and these current releases go to wgcma.vic.gov.au and follow the links from the homepage.

Published Tuesday 8th April 2020