Orange County Water District's Groundwater Replenishment System Is Now Producing Water

The Orange County Water District's (OCWD) Groundwater Replenishment System (GWR System) is arguably the largest operating advanced water purification facility (AWPF) in the world. With a capacity of 70 million gallons per day (mgd), the plant uses membrane filtration (MF), reverse osmosis (RO) and ultraviolet irradiation/advanced oxidation (AOP) to produce the highest quality recycled water. Commissioning and acceptance testing began in mid 2007 with the plant fully operational by the beginning of 2008. The AWPF is a new water source for Orange County, California, supplying water for groundwater recharge and the seawater intrusion barrier. At a total cost of /485 million dollars, the GWR System is an innovative and economical way to meet the growing water supply needs in Southern California. This paper will detail some of the testing requirements, highlight the operational successes, and describe some of the problems and the solutions encountered during startup.