Facing extended droughts and continued population growth, the Orange County Water District (OCWD) and Orange County Sanitation District (OCSD) partnered with CDM to plan and design the groundwater replenishment (GWR) system, which produces potable water for indirect reuse from highly treated wastewater. A model of sustainability, the project conserves and recovers limited water resources, reduces energy consumption compared to imported water transport, and supports economic vitality.
The multi-barrier approach of microfiltration (MF) and reverse osmosis (RO) followed by ultraviolet (UV) light disinfection ensures that all bacteria, emerging contaminants, and viruses are removed and protects public health and safety. The treated water is then injected into an underground seawater barrier or percolated into aquifers, providing a new water source for about 500,000 people.
Expandable to 130 mgd, the GWR System is the largest plant in the world using MF/RO/UV to purify treated wastewater into drinking water. A sophisticated distributed control system guides accurate and efficient process management—facilitating local computations, simplifying code maintenance, and enabling rapid adjustments. The easily-expandable system enables the thousands of input and output connections required for this instrument-intensive plant.
The environment-friendly plant reduced the regional power demand—less power is required to purify wastewater than to import a similar amount of water from Northern California or the Colorado River. The streamlined facility reduces the amount of treated wastewater released into the ocean, delaying the need for an additional ocean outfall, and provides economic benefits to the county by reducing maintenance costs.
The pioneering advanced water treatment facility helps drought-proof Orange County while providing safe, potable water to a growing population in an environmentally friendly and energy efficient way.
This project won the American Academy of Environmental Engineers 2008 Grand Award in Design.