Industry News

Abstract

This article announces that the Orange County Water District (OCWD) and the Orange County Sanitation District (OCSD) have received the 2008 Stockholm Industry Water Award for their pioneering work in developing the county's Groundwater Replenishment (GWR) system, which will provide enough water for an additional 500,000 Orange County, California, residents without diminishing groundwater resources for future generations. The Orange County GWR system, which is initially operational at 70 mgd, diverts wastewater that was previously discharged into the ocean and purifies it with a series of advanced techniques that include microfiltration, reverse osmosis, ultraviolet disinfection, and hydrogen peroxide. About half of the purified water is injected into Orange County's expanded seawater intrusion barrier. Orange County's original seawater intrusion barrier was built in the 1970s, and the GWR system's predecessor, Water Factory 21, provided the purified water that was injected into the original seawater barrier. The original system of injection and monitoring wells that was part of Water Factory 21 was expanded as part of the GWR system. The remaining half of the GWR system's purified water is piped to percolation basins in Anaheim where the water takes the natural path of rainwater as it filters through clay, sand, and rock down to the aquifer. Most of the drinking water for northern and central Orange County is drawn from the aquifer. The GWR system not only provides a drought‐proof source of water for Orange County and decreases the county's reliance on imported water from Northern California and the Colorado River, but the system also reduces the amount of wastewater that is discharged into the ocean.