The ALBERGA sheet is mostly underlain by crystalline rocks. Drilling information was used to assess factors controlling groundwater occurrence and the relationships between well yield and geological setting. A groundwater prospects map was compiled. In the crystalline rocks, useful supplies are limited to within 30 metres of the surface. Wells sited on photolinear features and in valleys, in thick saprolite are more likely to be successful. Saprolite is a more consistent aquifer than the fractured rock, with more wells yielding over 0.5 L/s and fewer over 2 L/s. The Adelaidean rocks have higher yields than the crystalline rocks, and optimum drilling depths of about 100 metres. Groundwater salinities vary from about 500 mg/L to at least 50 000 mg/L.