Salinity in the Murray Valley Salinity Province is primarily associated with the irrigation development on the Riverine Plains. This large province of about 170,000 ha is part of the Shepparton Irrigation Region that uses water diverted from the Murray River at Yarrawonga weir. It is underlain by intermediate to regional scale Groundwater Flow Systems beneath a largely flat landscape. Greatly increased recharge to the Groundwater Flow Systems due to irrigation development, poor surface drainage and the wetter climate phase from the 1950s to 1990s caused the watertable to rise to the surface, causing waterlogging and salinity.
Depth to watertable maps going back to the 1980’s can be found on the Goulburn-Broken CMA website (external link). These show the dynamic nature of the watertable, which declined and contracted during the 1999 - 2009 drought decade.
Salinity and high watertables have been managed through an integrated program that improved irrigation water use efficiency; built a surface drainage network; installed groundwater pumps to manage high watertables and supported environmental protection works and incentives.
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