The Perth Seawater Desalination Plant, located in Naval Base, south of Perth, Western Australia, turns seawater from Cockburn Sound into nearly 140 ML of drinking water per day, supplying the Perth metropolitan area. The salt water reverse-osmosis (SWRO) plant was the first of its kind in Australia, and became operational in 2006. It covers around 10 ha in an industrial park near the suburb of Kwinana Beach. Electricity for the plant is generated by the 80 MW Emu Downs Wind Farm located in the state's Midwest region near Cervantes. The wind farm contributes 270 GWh/year into the general power grid, more than offsetting the 180 GWh/year requirement from the desalination plant. The desalination plant, with 12 SWRO trains with a capacity of 160 ML per day and six BWRO (brackish water) trains delivering a final product of 144 ML per day, was expected to have one of the world's lowest specific energy consumption, due in part to the use of pressure exchanger energy recovery devices supplied by Energy Recovery Inc. The devices are isobaric chamber types which recover energy in the brine stream and deliver it to water going to the membrane feed at a net transfer efficiency at up to 98%. As a condition of its continued operation, the Perth plant has a comprehensive environmental monitoring program, measuring the seawater intake and brine outfall. Excess water from the plant is stored in the dams situated in the Darling Scarp. In early 2008, the plant was shut down on two occasions due to reduced dissolved oxygen levels in Cockburn Sound.