Andrew Reynolds, Acting Chief Executive, Murray-Darlin Basin Authority, Media Release, 7 September 2021
The Murray-Darling Basin Authority has increased daily releases from Hume Dam to 31GL to manage airspace.
The flow rate will keep Murray River levels similar to what they have been in the past few days – a little above channel capacity but well below minor flood level at Albury. The release rate is likely to change in response to changing conditions in the catchment.
We’re actively managing Hume Dam and our river operators are working around the clock to assess new inflow and weather information and manage releases. This includes close collaboration with the Bureau of Meteorology and WaterNSW.
Our priority is keeping the dam safe, capturing and storing water, and where we can, mitigating floods.
We are trying to manage inflows and increase airspace to help mitigate the impact of future rainfall events. This means that over the coming week, releases from Hume Dam may increase. A small rainfall event is forecast on the weekend. Releases may change in response to this or any rain.
However, the limited airspace currently available means that the ability to mitigate high flows is limited.
There is now a high chance of significant flooding downstream of Hume Dam if further heavy rainfall events occur. We are planning to create more airspace over the next couple of weeks.
Communities should not be complacent about floods downstream of Hume Dam. When the storage is near full, large flood inflows must be passed downstream as they arrive.
We advise people who live or work on the floodplain to ensure they keep up to date through the best sources of up-to-date information which are:
- The Bureau of Meteorology for information on flood warnings in their area
- WaterNSW Early Warning Network for releases from Hume Dam
- Their local State Emergency Service (SES).
Background
Hume Dam is effectively full and the MDBA is now in flood operations. This involves passing on any upstream flood event and, where possible, reducing impacts downstream of Hume Dam.
The MDBA has been hosting weekly briefings with downstream stakeholders while we have been in pre-flood operations. We have also provided further updates as conditions and our responses have changed significantly, as they did late last week where predicted rainfall increased from a 20mm forecast to 100mm.
The MDBA operates the Hume Dam in accordance with the rules set by state governments.
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.
When the dam fills, all flood waters will pass through the dam and head downstream along with the water entering from unregulated tributaries such as the Kiewa River.
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.
If you live or work on the floodplain, you need to be prepared for potential floods by:
• Developing a personalised flood plan
• Signing up to WaterNSW’s Early Warning Network, and
• Checking for up-to-date flood warnings on the Bureau of Meteorology website.
To sign up for WaterNSW’s Early Warning Network visit www.waternsw.com.au/ewn
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)
