Geophysics at Australia’s Desalination Plants

Abstract

In recent years major coastal desalination plants have been constructed at various locations around Australia. Engineering geophysics has contributed to the successful completion of these major projects. During 2009-10 two of Australia?s largest desalination plants with a combined capacity of 370Megalitres/day (upgradable to 670Ml/day) were commissioned in Sydney, NSW and at the Gold Coast, Queensland at a total cost of approximately $A2.5 billion. Case studies at these desalination plants discuss aspects of the land, borehole and marine geophysical technologies that were applied during the feasibility and design phases of these projects. These technologies were used to investigate geotechnical conditions at the proposed plant sites and along the land and marine sections of the sea-water intake and brine outlet tunnels. These studies had a significant impact on the geotechnical risk assessments and the final design of these desalination plants and involved the use of electromagnetic, gravity and seismic methods. The case studies demonstrate the value of appropriate geophysics to large civil engineering projects.