Aquifer interactions and their impact on groundwater resources in the Basalt plains of Western Victoria, Australia

Abstract

South of the West Victorian Uplands in southeastern Australia, a series of palaeorivers (so-called "deep leads"), buried beneath 30-120m of basalt, form a complex aquifer system (the Streatham Deep Lead System) which extends over an area of more than 2500 km 2. Groundwater quality both within the unconfined basalt aquifer and the deep lead aquifer ranges from high (suitable for human consumption) to very saline. Combining analyses of several natural environmental isotopes with hydraulic data show that the two aquifers are separated over much of the area. However, preferential recharge to the deep lead system occurs through eruption points, resulting in good quality groundwater in both aquifers in these areas. © 2007 Taylor & Francis Group, London.