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Water Treatment Project

Groundwater Replenishment System

Orange County Sanitation District (OCSD) & Orange County Water District (OCWD)

Since 2008, the Groundwater Replenishment System (GWRS), already the world’s largest indirect potable reuse facility, has been recycling treated wastewater into high-quality drinking water, and has produced more than 400 billion gallons of water. It now has another impressive notch in its belt: recycling 100% of OC San’s reclaimable wastewater flows as of December 2022. The GWRS can now produce up to 130 million gallons of drinking water a day (MGD), serving nearly one million people in north and central Orange County. The Final Expansion project included expanding the Advanced Water Treatment Facility, constructing a new pump station and two flow equalization tanks, rehabilitating a pipeline, and modifying OC San’s headworks to be able to segregate reclaimable and non-reclaimable flows.

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