26 May 2022
SOUTHERN BASIN WATER SHARING ARRANGEMENTS
The connected southern Murray Darling Basin extends across northern Victoria, southern New South Wales, and parts of South Australia, and comprises different catchments, irrigation regions, water storages, and waterways.
Each state in the southern Basin has their own unique suite of water entitlement products. Where rainfall and run-off occur in each catchment drives differences in state shares and hence how much water a state can allocate in a year.
The bulk of the water that supports southern Basin entitlements comes from highly productive catchments in the east of the Basin, particularly the Murrumbidgee, Goulburn-Broken, and the upper Murray.
The large storages in the upper catchments are another driver of water availability, including Lake Dartmouth, Lake Hume, Lake Eildon, Burrinjuck Dam, and Blowering Dam. The Snowy Mountains Scheme, and the Menindee Lakes on the Darling River, are also important water sources for the southern Basin.
Inflows upstream of Albury are shared 50:50 between Victoria and NSW. Below Albury, tributary inflows belong to the state in which the tributaries are located. South Australian monthly entitlement flows are supplied equally by Victoria and NSW.
Water in the Menindee Lakes is shared equally between Victoria and NSW when the volume exceeds 640GL and reverts to NSW control when the Lakes drop below 480GL.
An average annual volume of over 2,000GL is released from the Snowy Mountains Scheme into the southern Basin.
The MDBA Active Storage volume (Lakes Hume, Dartmouth, Victoria and Menindee) trended well above the long-term average for much of 2021-22 and was at the highest volume for the start of May recorded in the last 22 years.
The next webinar in this series, on Thursday the 9th June 2022, will discuss how irrigation allocation processes, carryover, and unregulated flows impact on southern Basin water availability.
Content source and further information:
Webinar PDF Slides