Dryland salinity occurrence in the Molyullah_Tatong Salinity Province is mostly found in the lowest parts of the valleys and drainage lines. This is in contrast to salinity in the neighbouring ‘Warrenbayne_Boho’ province, which tends to be more ‘break-of-slope’ type occurrence. Local and intermediate scale Groundwater Flow Systems in porous valley edge colluvium and valley alluvial sediments convey groundwater and salts to valley floor locations, where possible structural geologic controls (faults) or low permeability sediments restrict the deeper movement of groundwater, leading to the development of discharge areas.
High watertables followed the wetter 1980s and 90s, but the drought decade from 1999 reduced recharge allowing the watertable to decline. Groundwater levels rose again in response to the wet 2009 - 2011 years, but not to 1990’s levels.
Key management approaches rely on increasing plant water use and sympathetically managing groundwater discharge areas.
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