GWRS - Groundwater Replenishment System

GWRS - Overview● Current production

capacity of 70 mgd, enough water for 600,000 people

● Purifies already highly treated wastewater to near-distilled quality

● Provides additional peak wastewater flow disposal relief

Major Benefits● Reduces economic and environmental

impact of droughts, $478/AF with subsidies

● Provides all necessary low-turbidity water for the Talbert Seawater Barrier

History● Operational since January

2008

● Jointly funded by the Orange County Water District and the Orange County Sanitation District

● Largest issues were the lack of planning for diurnal flow and optimizing the decarbonation and lime stabilization process.

Flow Diagram

How it all works

Pre-Purification● first treated at the Orange County

Sanitation District (OCSD)

● 200 million gallons of wastewater per day

● bar screens, grit chambers, trickling filters, activated sludge, clarifiers and disinfection processes

● 0.2 micron in diameter

Step 1 Microfiltration

Step 2reverse osmosis

RO process● disinfects and

destroys any trace organic compounds

● NDMA, 1-4 Dioxane

Step 3 UV & H202

distribution35 million gallons → injected into seawater intrusion barrier

● Water Factory 21 (WF-21)● 23 wells along the coast

35 million gallons → pumped into Anaheim groundwater recharge basins

● 13 mile pipeline to Kraemer and Miller

Future DevelopmentsPlanning to add an additional 30 mgd

References

• R. Herndon and M. Markus, Orange County Water District, 18700 Ward Street, Fountain Valley, California 92708, Large‐Scale Aquifer Replenishment and Seawater Intrusion Control Using Recycled Water in Southern California.

• William Dunivin, Mehul Patel, and James H. Clark, Orange County Water District Black & Veatch Corresponding author e-mail: BDunivin@ocwd.com, Building on Lesson Learned for Expanding the Next Phase of the Groundwater Replenishment System

• GWRS Technical Brochure, http://www.gwrsystem.com/images/stories/AboutGWRS/GWRS%20Technical%20Brochure.pdf