South-West Western Australia (SWWA) is experiencing a long-term drying trend. Historically, Perth, the biggest city in the region with a population close to two million, has relied on reservoirs for its water supply. However, modelling of future climate of the region suggest further reduction in rainfall, which poses a threat to water security. To tackle the situation, the water authority that manages water supply in SWWA, has worked to diversify its water resources. Two desalination plants have been constructed as a part of a plan to ensure long-term water security in the region.