NCEDA analysis of IDA World Congress technical sessions
Management of drinking water quality from seawater desalination: Case studies from Western Australia
Author: Mr Noel Winsor, Water Corporation
Noel Winsor explained that in Western Australia (WA), seawater desalination is now a key component of the water supply infrastructure. The Water Corporation currently owns three plants: Perth Seawater Desalination Plant (PSDP) at Kwinana, a seawater desalination plant providing industrial grade water on the Burrup Peninsula, and the new Southern Seawater Desalination Plant (SSDP) at Binningup. Provision of safe drinking water to customers is one of our highest corporate priorities, with legal requirements placed on the organisation by the Department of Health and Economic Regulation Authority. In WA, as a result of the drying climate, seawater desalination is now a key strategic source of drinking water. The case studies presented in this paper show a number of potential impediments exist in providing adequate protection of our marine intakes from the influence of natural or anthropogenic contamination.
Source protection is constrained by:
• No direct guidance for the management of marine intakes and desalination in the current (2004) Australian Drinking Water Guidelines (ADWG),
• Limitations with the application of current source protection legislation for marine intakes,
• Inability to prevent inappropriate land use development in coastal areas adjacent to marine intakes, and
• Perception that seawater desalination provides the ultimate barrier to contamination and source protection is not essential.
At the time, seawater desalination was a relatively new technology in Western Australia, so tools, processes and procedures were developed by the Water Corporation to ensure supply of safe drinking water. The development, use and role of Source Protection Strategies (SPS), Water Safety Plans (WSP) and water quality management plans in providing safe drinking water was described.
However, observations of the marine environment since 2006 suggest that there is now an urgent need to amend current legislation to support proactive management of all activity and development around seawater intakes.
