Perth, Western Australia, Australia

Perth's Groundwater Replenishment Scheme at Beenyup recharges advanced-treated wastewater into deep aquifers for later drinking-water abstraction, the Southern Hemisphere's first such scheme. Capacity was doubled to 28 GL/yr in 2022 (stage 2 cost about A$262-320M). Approval was preceded by a 3-year trial, a visitor center and more than 2,500 public tours, which produced roughly 70% public support, and no referendum was held. The scheme is one pillar of a rainfall-independent supply portfolio built in response to permanent drying: streamflow into Perth's dams has fallen about 80% versus pre-1975 levels.