Orange County Water District’s Groundwater Replenishment System (GWRS) is the largest indirect potable reuse treatment plant in the world. The GWRS takes treated wastewater from multiple wastewater treatment plants and purifies it using a three-step advanced treatment process consisting of ultrafiltration, reverse osmosis, and ultraviolet light with hydrogen peroxide.
Two of our advanced water technologies—MemCor™ submerged ultrafiltration modules and FilmTec™ reverse osmosis (RO) membranes—are key to the treatment process that is now transforming 100% of the reclaimable wastewater into a new source of water for the region. The final expansion of the GWRS increased treatment capacity from 100 to 130 million gallons per day.
The high-quality water is used to recharge aquifers and refill the Orange County Groundwater Basin, becoming part of the drinking water supply for 2.5 million people in north and central Orange County in California. GWRS water is also sent to injection wells located along Orange County’s coast to create a seawater intrusion barrier that protects groundwater supplies.
