Salinity Province 115, Telopea Downs

The large Telopea Downs Salinity Province is located on the South Australian border and comprises an arid landscape where naturally high salinity levels have accumulated over thousands of years. Key landform features include Quaternary linear sand dunes and sand plains in the northern half and older Tertiary aged Parilla Sand plains in the southern half, which is where most of the region’s cropping occurs.

A regional scale Groundwater Flow System (GFS) in marine and alluvial sediments underlies the area however; dryland salinity is mostly associated with the local and intermediate scale GFSs of the overlying aeolian dunes and ridges. These feed groundwater into poorly drained inter-dune swales and depression areas where sodic soils and seasonal waterlogging combine to leave saline soils and occasional evaporate deposits.

Farming best practices should aim to avoid the disturbance of, and protect, known waterlogged and saline sodic soil areas. In addition, concentrating farming effort on adjacent up-slope soils with increased perennial pastures and native re-vegetation would reduce recharge during wet periods.