ABSTRACT
This chapter explains the hydrogeological provinces. It discusses the two principal aquifer groups and outlines the principal groundwater management issues. Given the relatively uniform nature and minor significance of the Basement Aquifers they are described in general terms only, while the described of the Cainozoic Aquifers is more detailed and each hydrogeological province is dealt with separately. Palaeozoic igneous rocks including the Mount Dandenong Volcanics and associated intrusives, outcrop over a small part of the region forming minor water table aquifers. The basement aquifer generally exhibits very low primary porosity and hydraulic conductivity, however tectonic deformation and fracturing have produced higher secondary porosity and a fractured rock aquifer of low to moderate hydraulic conductivity. The Nepean province contains a substantial groundwater resource and the Bridgewater Formation is widely used for irrigation, stock and domestic purposes. Bore yields of up to 25 L/sec are reported in the Boneo area.
