Hattah Lakes is a complex of more than 20 semipermanent freshwater lakes over an area of 48,000 ha. The complex forms part of the Hattah-Kulkyne National Park. The complex is adjacent to the River Murray in north-west Victoria, and the ecology of the lakes and floodplain is strongly influenced by flooding regimes.
The Hattah Lakes system is naturally filled when there are high flows in the River Murray and some lakes hold water for several years after floods recede. Regulation of the River Murray has significantly reduced the frequency and magnitude of natural floods through the Hattah Lakes system.
Large-scale engineering works were completed under the Living Murray program to improve water regimes at Hattah Lakes under low-flow conditions. Pumps and regulators are used to deliver water to parts of the floodplain and then retain and/or discharge it to provide the water regimes that support the environmental values of the system.