How much fresh water would the Lower Lakes need to avoid having to build a temporary weir?
The preferred option to address the situation in the Lower Lakes is to provide additional flows of fresh water from the Murray-Darling Basin. To give some perspective to the volumes of water involved, the flow to the lakes in 2008-09 is 350 gigalitres. An additional 450 gigalitres would be required to maintain lake levels, that is, to balance evaporation losses. The lakes have dropped from a normal operating level of (0.7 metres above sea level to 0.8 metres below sea level), equivalent to about 1,000 gigalitres. To flush the salts that have been transported to the Lakes from the entire Murray-Darling Basin would require additional water. To achieve this would require extensive collaboration of the Murray-Darling Basin jurisdictions and the Australian Government, and possibly re-allocation or purchase of water from existing users (irrigators, the environment elsewhere in the Murray-Darling Basin), possibly over a period of years. It is uncertain whether such volumes would be available
