On November 27th, 2019, I visited Orange County Water District (OCWD)’s Groundwater Replenishment System (GWRS) in Fountain Valley, CA. I used to live and work in Fountain Valley and had visited The GWRS many times for my research project. The GWRS is the world largest advanced water purification facility (AWPF) that has a current production capacity of 100 million gallons per day (MGD), which is being expanded to 130 MGD. The GWRS treats secondary treated wastewater provided by the adjacent Orange County Sanitation District (OCSD)’s Plant No. 1 using a series of advanced treatment processes including microfiltration (MF), reverse osmosis (RO), and UV/hydrogen peroxide advanced oxidation process (AOP). Excess carbon dioxide is removed from the purified water and then lime is added. The GWRS produces extremely clean drinkable water at a cost of 0.26 cents per gallon ($850 per 1 acre foot). Once the final expansion to be completed in 2023, the GWRS will be able to supply enough water for 1 million people in Orange County (approximateley 1/3 of its population). Public tours are available at the GWRS. You can drink the purified water at the end of the tour.
The RO process at the GWRS can recover 85% of permeate (purified water), while producing 15% of concentrate (currently at a flow rate of 18 MGD). This concentrate is currently sent to the OCSD’s Plant No. 2, which is located in Huntington Beach, and then discharged to Pacific Ocean.
Microfiltration (MF)
Reverse Osmosis (RO)
UV/Hydrogen Peroxide Advanced Oxidation Process (AOP)
Water Tasting Station at the GWRS
I Drink Purified Wastewater, Rain or Shine