The Murray–Darling Basin Authority, Media Release, 10 August 2021

The Murray–Darling Basin Authority has started releasing a small volume of water from Hume Dam to maintain airspace for the inflows expected from rain forecast by the Bureau of Meteorology over the coming months.

The Bureau is forecasting wetter-than-average conditions in the Upper Murray catchments which means there is an increased chance of flooding. Hume Dam is currently sitting at just under 90 per cent of capacity and all indications suggest the dam will fill.

MDBA Executive Director of River Management Andrew Reynolds said the small releases started last Friday and were currently 4000 megalitres per day.

“We release water from Hume Dam to create airspace only when we are confident the dam will fill. Recent rain events have increased the dam level to nearly 90 per cent capacity,” Mr Reynolds said.

“These initial pre-releases will stay within river channel and not cause downstream flooding, as they are relatively small volumes.

“We are letting this water out as a precautionary step to reduce the potential impact of flooding downstream in the coming months.”

Hume Dam’s primary purpose is water security – it plays a crucial role in managing flows and securing water along the Murray River, including to Adelaide. The MDBA needs to fill Hume Dam before irrigation demands start to exceed inflows, and the level starts to drop. This ensures water allocations are maximised.

The MDBA operates the Hume Dam in accordance with the rules set by state governments.

“Every day we evaluate conditions based on Bureau of Meteorology data, predicted inflows and historical records to determine how to best manage the dam,” Mr Reynolds said.

“It is important to note that when the dam fills, all flood waters pass through the dam and head downstream along with the water entering the river from the tributaries such as the Kiewa River.”

Given the rapid rise of water in storage in the past few weeks, without Hume Dam the downstream areas of the River Murray would already be experiencing flooding.

All agencies are working together to keep communities informed and safe should flooding occur.

The Bureau of Meteorology is responsible for issuing flood warnings to the public. Check www.bom.gov.au/australia/warnings for up-to-date flood warnings in your area.

For more information about how dams are managed to reduce the impact of flooding visit: How are dams being managed to reduce the impact of flooding? | Murray-Darling Basin Authority (mdba.gov.au)