Orange County Water District, Orange County, California (www.ocwd.com)
is the world’s largest advanced water purification system for potable reuse. It takes treated wastewater that otherwise would be sent to the Pacific Ocean and purifies it using a three-step advanced process. Consisting of microfiltration, reverse osmosis, and ultraviolet light with hydrogen peroxide, this purification process produces high-quality water that exceeds all state and federal drinking water standards. This water is injected into a seawater barrier and pumped to recharge basins where it naturally percolates into the groundwater basin. Operational since January 2008, the GWRS can produce 70 million gallons (MGD) of high purity water every day. By 2015 these figures are projected to increase to 100 MGD when purification facilities are expanded.