A hydrologic investigation of salt-affected soils in an alluvial plain of the Hawkesbury River, N.S.W

An alluvial plain had noticeable salinization of low-lying surface soils after a succession of wet years. Piezometric investigations showed that the water-table was permanent and of low hydraulic gradient. Salinity measurements provided the ground water pattern of salinity and the soil-salt distribution relative to water-table depth. The critical depth for the water-table associated with surface salinization was 3 ft. The influence of a neighbouring saline-water bearing sedimentary shale deposit is examined, and the probable source of salt in the alluvial plain soils is suggested. A possible method of controlling this salt, by control of the input potential of the watertable, is discussed.