The area of interest divides into two groundwater environments: a Mesoproterozoic hard rock environment containing fresh water in fractures and saprolite; and a younger sedimentary environment containing more saline water in Adelaidean/Tertiary/Quaternary sediments. The hard rock area is mostly confined to the northern ranges, but may extend under the sediments. Recharge is provided locally in the ranges by higher rainfall, rapid surface concentration of runoff, and ready absorption of water into the fractured/weathered zones. Such resources have low salinity and a low yield, but are sufficient for local communities (<1 L/s). The salinity increases with residence time in the ground, and high nitrate levels are a problem. There may be a gradual lithological transition between these hard rock aquifers and the palaeochannel type of Tertiary aquifer. Little is known about the resource in consolidated sediments because it tends towards high salinity and is therefore of little immediate use for current demand. Moreover, no high-yielding aquifers have yet been intersected. There is the possibility of larger reserves in the Levenger Graben, with the added possibility of low salinity water and better yields. The provenance of the water in these sedimentary reserves is uncertain, but probably comes ultimately from the hard rock area, with some local recharge. The major sedimentary groundwater environment is the unconsolidated Tertiary sediments which are concentrated mainly in the palaeochannels. The search for water in the hard rock area is best done on an as needed basis, since a broad scale analysis of groundwater provenance is of limited value in this environment. An improvement in the availability of basic data, by putting as much of the information as possible on GIS, would help, as would improvements in techniques for pinpointing drill sites. In the sedimentary area, some regional work to better define the palaeochannels and grabens and to test for water quality would be beneficial, particularly if saline water will be of value for mining or as feedstock for a desalinization plant. Such a study might indicate some larger scale resources.