California is moving forward with its plans for the long-anticipated $3 billion Sites Reservoir in the Sacramento Valley by seeking a construction manager. The project aims to address the state's water storage challenges amid ongoing droughts and increasing wildfire threats in southern regions.

First conceptualized in the 1950s, the project received a boost in 2018 with $800 million in funding and is being spearheaded by the Sites Project Authority, established in 2010. The off-stream reservoir, which will cover 6,000 square kilometers and reach depths of 90 meters, is set to become the state’s eighth-largest artificial lake, capable of storing enough water to supply 7.5 million people annually.

The construction manager will oversee the project using the construction manager at-risk (CMAR) model, intended to “optimize project delivery, manage risks, encourage local community collaboration, and provide the best value for project participants,” per the Sites Project Authority.

The reservoir's design includes two 90-meter-high main dams, seven saddle dams, three dikes, a concrete spillway, a 400-meter tunnel, and 10 kilometers of upgraded roads.

“This next step in our contracting process marks a critical milestone for Sites Reservoir as it progresses from planning to construction,” said Fritz Durst, Chair of the Sites Project Authority Board of Directors. “As one of the largest water infrastructure projects currently under development in California, Sites is a significant opportunity to enhance water reliability for the benefit of our communities, farms, and environment.”

The reservoir will provide an additional 1.5 million acre-feet of water storage, improving flexibility and reliability. It will store excess stormwater from the Sacramento River while adhering to water rights and regulatory requirements, releasing water during drier periods to benefit communities, agriculture, businesses, and wildlife.

Interested firms must submit qualifications by March 10. Shortlisted candidates will later submit detailed proposals and attend interviews. The chosen firm will begin pre-construction services in fall 2025, with construction slated to start in 2026 and completion projected for 2032.