The California State Water Resources Control Board on Wednesday approved a water rights permit for the Sites Reservoir, clearing the way for construction of the state’s largest new water storage project in more than five decades, the Sacramento Bee reported.
The reservoir, planned for Colusa and Glenn counties near Maxwell about 70 miles northwest of Sacramento, would hold up to 1.5 million acre-feet of water. Construction is scheduled to begin in summer 2027, with costs now projected between $6.2 billion and $6.8 billion, according to the Bee.
Permit Caps Years of Debate
The board’s decision on Nov. 4 marks the final major regulatory approval for a project that has drawn objections over cost, environmental harm and tribal concerns, the Bee reported. A draft approval issued in March drew sharp criticism from environmental advocates.
Harrison Beck of the Center for Biological Diversity warned that the decision “did not address serious threats to the Sacramento River ecosystem and imperiled fish populations,” according to the Bee.
A Project Decades in the Making
Federal officials signed off on an environmental review in January, a step that could cover up to a quarter of construction costs. Interior Secretary Doug Burgum said the Trump administration backed the project to expand water reliability for communities and agriculture, the Bee reported.
California has moved the project quickly since Gov. Gavin Newsom signed 2023 legislation that expedites legal challenges under the California Environmental Quality Act. Newsom has pitched Sites as a critical piece of the state’s climate adaptation strategy alongside the $20 billion Delta Conveyance tunnel project, according to the Bee.
A Yolo Superior Court ruling in 2024 rejected a coalition lawsuit from groups including Friends of the River and the Sierra Club, finding the project’s environmental review legally adequate and clearing a key court challenge, the Bee reported.
Sites Reservoir has reached a major milestone after decades of planning. Yesterday, @CaWaterBoards issued the Project’s water right decision and permit, clearing a critical pathway toward construction. One step closer to a more resilient California. pic.twitter.com/0q4PiBAfmS
Costs Surged Past $6 Billion
Construction costs have risen due to inflation and material shortages, pushing the estimate above $6.2 billion, the Bee reported. The project calls for two earthen dams 300 feet high and nine smaller dams ranging from 20 to 100 feet high.
| Detail | Figure |
|---|---|
| Location | Colusa and Glenn counties, near Maxwell |
| Dimensions | 13 miles long, 4 miles wide, 260 feet deep |
| Capacity | 1.5 million acre-feet of water |
| Cost | $6.2 billion to $6.8 billion |
| Construction start | Summer 2027 |
What the Permit Does Not Settle
Environmental advocates say the approval leaves unresolved questions about harm to the Sacramento River and imperiled fish, concerns the state board did not fully address in its decision, the Bee reported. Whether the final cost stays within the $6.2 billion to $6.8 billion range is uncertain as construction approaches.
Questions Readers Ask About Sites
Who still opposes the reservoir? Environmental groups including the Center for Biological Diversity, Friends of the River and the Sierra Club challenged the project in court and criticized the permit, with Beck warning it does not address threats to the river ecosystem and imperiled fish.
How does Sites fit with other state water projects? Gov. Gavin Newsom has presented Sites alongside the $20 billion Delta Conveyance tunnel as parts of California’s climate adaptation strategy, according to the Sacramento Bee.
When does work actually begin? Construction is scheduled to start in summer 2027, following the water rights permit approved Nov. 4, the Bee reported.
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