Salinity management measures set for roll out

Research for the A$1.2 million project has been delivered through the Water for Healthy Country Flagship. The project is run by the Wallatin Wildlife and Landcare Group and explores a combination of engineering and agronomic solutions to salinity identified by the landholders themselves.

CSIRO and the Grains Research and Development Corporation have contributed funding and research support to monitor and evaluate the trials and provide a framework for landowners to make better informed decisions.

CSIRO’s Michael Robertson, who is leading the research component of the project, says “the result will be a ‘how-to’ guide of remedial activities, with a checklist of biophysical, economic and social pre-conditions needed to limit risk. Crucially, the project also focuses on the urgent need to protect vital assets such as water and natural resources.”

David Leake, chairman of Wallatin Wildlife and Landcare, says that in the first phase of the CDI a range of salinity management options have been demonstrated in 14 projects scattered around the catchment.

“The open day on 18 October was a great opportunity for people to see the projects first hand,” Mr Leake says.

In the CDI’s second phase, growers will co-invest with CDI funds on a catchment scale roll-out, using best practices identified during phase one.

CDI project manager Glenice Batchelor says: “In some projects the aim is to increase groundwater discharge by constructing deep drains, pumping systems and locating siphons at seeps. In addition, commercial saltland and conservation plants have been planted to use the water.

“Other options include planting riparian vegetation along waterways installed with water flow inhibitors and sediment traps, and planting perennial and annual pastures and salt tolerant vegetation. Lucerne has been planted in low salinity and high water yielding areas, with growers hoping to benefit from additional biomass during the autumn feed-gap.”

The project includes three sub-catchments spreading across 44,457 ha, including the Wallatin/O’Brien catchments and Woolundra Lakes.

Salinity expansion forecasts for WA are concerning. According to WA Department of Agriculture hydrologist, Dr Richard George, there are between one and two million hectares of dryland salinity in WA and between two and four million hectares at risk from rising ground water, amounting to A$400 million in lost agricultural production.

The CDI project is an example of how local, state and federal groups can collectively tackle salinity. Various state departments, Curtin and Murdoch Universities and the University of Western Australia, and a range of private contractors have also contributed.