THE key recommendation in the Native Fish Strategy for the Murray Darling Basin 2003-2013 – a document developed by the Murray Darling Basin Commission, (MDBC) and adopted by the Murray Darling Basin Authority (MDBA) – was the need to address the issue of cold water pollution in particular from the Hume dam.
The strategy, published ten years ago, includes comment that cold-water pollution abatement is a “clearly definable, tangible, cost-effective intervention” that can be completed for the major storages in the Murray Darling Basin within ten years, through a combination of engineering and operating changes. The strategy was to run from 2003 to 2013 with the objective of returning native fish to 60 per cent of their pre-European levels.
Hume Dam, like most of the dams throughout the Murray Darling, have outlets for irrigation positioned at depth, so water release occurs as a jet of cold water. Releases are typically made in spring and this is the same time Murray cod and other native fish like to spawn. 
Jennifer Marohasy BSc PhD has worked in industry and government. She is currently researching a novel technique for long-range weather forecasting funded by the B. Macfie Family Foundation.