For Orange County’s Groundwater Replenishment System Expansion, Shimmick delivered a three-step advanced process consisting of microfiltration, reverse osmosis and ultraviolet light with hydrogen peroxide to produce water that meets and exceeds state and federal drinking water standards. The new 30 million gallon per day (MGD) expansion, completed in 2023, created an additional 31,000 acre-feet per year of new water supply and expanded the facility’s capacity to provide water for one million people.
Shimmick increased the capacity of OCSD’s existing advanced water treatment facility from 100 to 130 million gallons per day, making Orange County home to the world’s largest wastewater recycling plant. As part of the expansion, Shimmick installed pumps, chemical storage tanks, chemical dosing pumps, blowers, de-carbonators, and electrical components. The work also included the construction of conveyance facilities at the Orange County Sanitation District’s Plant No. 2, which included a pump station and building, two prestressed concrete tanks, piping and valving, weir boxes, and sluice gates.
Shimmick also performed demolition, site clearing and preparation, and disposal of excavated materials; installation, assembly and connection of new process piping, pumps, and equipment; and modification to existing concrete structures and construction of new concrete structures.
Shimmick self-performed deep pile foundation, deep ground improvements, trenching, and hand excavation, as well as sheeting, shoring, and bracing. Additional work included installation of a new pump station; prestressed concrete above ground storage tanks, and concrete metering and valve vaults; extension of existing and installation of new site and interior piping, valves, meters, and vaults; lining and coatings; installation of new pipe supports; site restoration, paving, and grading; site security; and traffic control.
Electrical work included modifying existing and installing new conduit, wiring, power and control systems, and integration and upgrading of the plant control system.