COWI to manage construction of IRWD’s Syphon Reservoir expansion

COWI, in joint venture with GFT (formerly Gannett Fleming), has been selected by the Irvine Ranch Water District (IRWD) as construction manager for the district’s landmark Syphon Reservoir Improvement Project — the largest capital project in IRWD’s history and one of Southern California’s most significant recycled water infrastructure upgrades.

The project will expand Syphon Reservoir’s capacity tenfold to 5,000 acre-feet, allowing greater storage of recycled water for irrigation and non-potable use. Once complete, the reservoir will enhance regional water supply reliability, reduce imported water demand and strengthen climate resilience for the growing Orange County region.

Under the multi-year contract, the COWI–GFT team will provide comprehensive construction management services, including constructability reviews, contractor support, risk management, quality assurance and environmental coordination to ensure compliance with California’s stringent dam and water quality standards.

“This is a significant milestone for COWI in Southern California,” said Arun Parsons, vice president of COWI North America, in a press release. “We’re impressed by IRWD’s bold implementation of the largest project in their history to maximize the use of recycled water. With our experience delivering dam and reservoir projects under California’s stringent requirements, we are well positioned to guide this project through construction.”

IRWD is advancing the Syphon project as part of its long-term strategy to expand recycled water reuse and reduce reliance on imported supplies.

The Syphon Reservoir expansion joins a growing portfolio of major water infrastructure projects managed by COWI across California, including Anderson Dam, Folsom Dam and Lake Mathews.