Lake Oroville Update - March 14, 2025

Flood Control Releases from Lake Oroville Increased

The Department of Water Resources (DWR) has increased federally required flood control releases from Lake Oroville to maintain flood protection for downstream communities. Water is being released through the Hyatt Powerplant for energy production and from Oroville Dam’s main spillway. Atmospheric rivers have delivered rain and snow to the Feather River watershed this week, elevating inflows into Lake Oroville and requiring increased flood control releases. DWR continues to conserve as much water supply as possible in coordination with the U.S. Army Corps of Engineers (USACE). Releases are subject to change based on ongoing weather conditions.

 

Between October and June, DWR is required to operate Lake Oroville for flood control under federal Water Control Manual guidelines set by USACE. These federal regulations establish a set storage space that is reserved to capture inflows from rain and future snowmelt, while protecting downstream communities from damaging flood events through water releases. Releases to the Feather River are coordinated closely with USACE and other downstream water operators.

 

Current reservoir levels are as follows, though estimates may change quickly:

• Current Oroville Reservoir Level: 864 feet elevation
• Current Storage Capacity: 85 percent
• Total Releases to the Feather River: 10,000 cubic feet per second (cfs)

 

Lake Oroville is the largest storage facility in the State Water Project, providing flood protection while supporting environmental and water delivery needs to 27 million Californians. Some water released from Lake Oroville is distributed locally for agriculture benefits, while the remaining Feather River releases flow south through the State Water Project system to reduce salinity effects in the Delta, provide irrigation for crops in the Central Valley, and eventually make their way to Southern California. DWR continues to monitor lake levels, weather forecasts, and mountain snow levels to optimize water storage while allowing for carryover storage into next year.

 

Forecast-Informed Reservoir Operations at Lake Oroville Can Increase Region’s Resilience to Floods

A new report released this week shows that changes to reservoir operations at Lake Oroville and New Bullards Bar Reservoir can further reduce flood risk for communities along the Yuba and Feather rivers during extreme atmospheric river storm events and potentially benefit water supply during drier periods. The approach, known as Forecast-Informed Reservoir Operations, or FIRO, uses improved monitoring, weather, and runoff projections to build more flexibility and efficiency into reservoir operations.

 

In the largest FIRO assessment to date, DWR and Yuba Water Agency (Yuba Water) partnered with the Center for Western Weather and Water Extremes (CW3E) at UC San Diego’s Scripps Institution of Oceanography and the U.S. Army Corps of Engineers’ (USACE) Engineering Research and Development Center to evaluate if FIRO could be implemented at both reservoirs to reduce downstream flood risk without negatively impacting water supplies. Lake Oroville is managed by DWR and New Bullards Bar is managed by Yuba Water.

 

Using historical forecasts, reservoir storage and river flow data, scientists found that FIRO, combined with a planned second spillway at New Bullards Bar, could provide additional flood storage capacity in the Yuba-Feather system and reduce downstream peak flows during prolonged storms like the 1986 and 1997 floods that devastated Yuba County.

 

“California’s reservoirs play a critical role in safeguarding our communities from floods and maintaining our state’s water supply, especially as we continue to see more extreme weather events in the form of larger, wetter, and more frequent storms and longer, more severe periods of drought,” said DWR’s State Climatologist Dr. Michael Anderson. “The Yuba-Feather FIRO Viability Assessment is an important step toward improving flood protection to communities downstream while managing California’s valuable water resources for decades to come.”

 

Learn more about the Yuba-Feather FIRO Final Viability Assessment in DWR’s news release.

 

Ongoing Road Closure for Tree Removal

DWR and its partners at the California Conservation Corps (CCC) and Butte County Sheriff’s Office continue the closure of a portion of Oro Dam Blvd. E. between Canyon Drive and Oro Powerhouse Road for tree and debris removal. A full road closure will continue to be in effect Monday through Thursday between 7 a.m. and 4:30 p.m. March 17-20. DWR is taking advantage of the closure to drop and clear large hazard trees that were damaged by the July 2024 Thompson Fire, in addition to performing routine fuel load reduction activities to minimize fire risk in areas surrounding Lake Oroville.

 

DWR’s Fuel Load Management Plan is dedicated to reducing wildfire risk, enhancing public safety, and improving forest health around Lake Oroville. During vegetation management activities some trails within the Lake Oroville State Recreation Area may be intermittently closed. Trail users should use caution in active work areas and follow all posted signage.

 

Vegetation management remains a top priority for DWR and its partners, including CAL FIRE, the Butte County Fire Department, the Butte County Sheriff’s Office, the CCC, the California Department of Fish and Wildlife (CDFW), State Parks, local tribes, and the Butte County Fire Safe Council.

 

Stop the Spread of Golden Mussels

Boaters and recreationists can help combat the spread of a new invasive species recently discovered in California waterways – the golden mussel. Despite its flashy name, this species poses a significant threat to infrastructure and the ecological health of all state waterways.

 

Golden mussels range from ¾ inches to 2 inches in size and have a light to dark yellowish-brown to brown-colored shell. When golden mussel populations are established, they are difficult to control since they can become very abundant and are easily spread to new waterbodies. If left unchecked, they can alter aquatic ecosystems by filter-feeding on planktonic algae and changing the habitat structure, impact water delivery systems by clogging small-diameter pipelines, screens, and filters, and impact recreation by fouling boat hulls and motors and clogging intakes and cooling lines.

 

To prevent the spread of invasive mussels, DWR routinely monitors for these species and acts to prevent their spread to non-infested waters. When recreating on California’s waterways, always remember to:

• Clean off aquatic plants and animal material from your boat, trailer, and equipment before leaving the ramp or parking lot.
• Drain ballast, bilge, live-wells, and other water-containing devices, and never drain back into the waterway.
• Dry equipment before launching into another body of water.

 

Current Lake Operations

Lake Oroville is at 864 feet elevation and storage is approximately 2.9 million acre-feet (MAF), which is 85 percent of its total capacity and 124 percent of the historical average.

 

Feather River flows are at 900 cfs through the City of Oroville with 9,100 cfs being released from the Thermalito Afterbay River Outlet (Outlet) for a total Feather River release of 10,000 cfs downstream. DWR continues to assess Feather River releases daily. 

 

The public can track precipitation, snow, reservoir levels, and more at the California Data Exchange Center. The Lake Oroville gage station is identified as “ORO.”

 

All data as of midnight 3/13/2025.

 

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