Lake Oroville Update - December 20, 2024

A Year in Review

Northern California’s significant rain and snow levels in 2023 continued to benefit Lake Oroville at the start of 2024. Rising reservoir levels from January storms prompted DWR to conduct flood control releases from Oroville Dam’s main spillway for the second year in a row. Releases began Jan. 31 and continued intermittently throughout the spring, providing critical flood protection to downstream communities. DWR maintains storage space in Lake Oroville during the typical wet weather months to ensure adequate space remains in the reservoir to capture runoff from rain and spring snowmelt. Releases are coordinated closely with the U.S. Army Corps of Engineers and other water operators and adjusted as needed.

 

The Feather River watershed received enough precipitation and snowpack runoff in the first months of 2024 to fill Lake Oroville to capacity by early May for the second year in a row. As the largest storage facility in the State Water Project, Lake Oroville helps provide water to 27 million Californians and 750,000 acres of farmland, making spring an important time for water project operators to fill reservoirs ahead of dry months.

 

With a full reservoir providing prime recreation opportunities at the Lake Oroville State Recreation Area, the California Department of Parks and Recreation (State Parks) completed improvements to reopen the Bidwell Canyon Gold Flat Loop Campground. In addition to repaving campground access roads, three of the 37 tent/RV camping sites received accessibility upgrades with parking stalls and a clear path of travel to accessible restroom and shower facilities. Upgrades to the campground also included new water and sewer facilities to complement new power hookups that were completed in recent years. 

 

In late June, DWR announced an update to Lake Oroville’s storage capacity. Because decades had passed since Oroville Dam’s construction, DWR sought to assess whether sedimentation (rock and silt settling on the lakebed floor) had altered Lake Oroville's storage capacity and topography significantly. Using an airplane-mounted LiDAR (Light Detection and Ranging) laser system and multibeam-sonar bathymetry instruments, highly detailed 3D topographic terrain models of the bottom of the lake were created, which DWR engineers used to calculate a new storage capacity of 3,424,753 acre-feet, approximately 3 percent less than previously estimated.

 

In early July, the Thompson Fire threatened the Lake Oroville State Recreation Area and several DWR facilities including the Hyatt Powerplant, Field Division main office, and Lake Oroville Visitor Center, with DWR activating its emergency Incident Command Team in response. While normal operations resumed by July 4, several recreation trails near the Diversion Pool and in the Potter’s Ravine area remain closed for repair and hazard tree removal. DWR and State Parks continue to assess fire impacts to recreation facilities and prioritize recovery efforts.

 

In August, DWR’s Oroville Field Division hosted emergency preparedness exercises for staff and partnering local emergency management agencies. A tabletop exercise included a review of the Oroville-Thermalito Complex dams, inundation maps, and an overview of DWR’s incident command team structure which follows National Incident Management System (NIMS) guidelines established by the Federal Emergency Management Agency (FEMA). A second, in-depth functional exercise had DWR staff and emergency management partners responding to a mock emergency scenario. DWR leads emergency preparedness trainings on a yearly basis to ensure Oroville Field Division staff readiness for any type of emergency or incident. The exercises reinforce DWR’s commitment to enhancing emergency preparedness and maintaining relationships and collaboration with local emergency response partners.

 

Construction work also continued on the River Valve Outlet System (RVOS) at Oroville Dam. The system is a series of two parallel outlet conduits, each with two valves, that have the capacity to draw water from deep in Lake Oroville for release. The RVOS is a critical feature of the dam, providing the ability to discharge cold water to the Feather River to maintain water temperatures necessary for fish health. It also ensures the ability to maintain Feather River flows through RVOS releases during drought years, especially if reservoir levels drop below Hyatt Powerplant’s water intake structures.

 

DWR also made progress on a project to improve a 1.5-mile section of the Brad Freeman Trail between Cherokee Road and the Highway 70 Garden Drive overpass. Work this fall included paving an 8-foot-wide asphalt path and the installation of accessible box gates at trail entrance points, which restrict vehicles while still providing access for equestrians, bicyclists, and pedestrians. Future work is weather dependent and will include a 4-foot-wide decomposed granite path for pedestrians. The improvement project is supported by a Land and Water Conservation Fund grant through the National Park Service, with remaining funding for the $700,000 project provided by DWR.

 

Fuel load reduction and fire mitigation work continued on DWR property along Oro Dam Blvd. East near the Hyatt Powerplant, the Bidwell Canyon/Kelly Ridge area, and the Loafer Creek State Recreation Area. DWR's Fuel Load Management Plan is reducing hazardous fuels and the risk of catastrophic wildfire by thinning vegetation using hand and mechanical methods, accompanied by chipping. By proactively reducing ground fuels, thinning overgrown vegetation, and removing dead and dying vegetation, firefighters have a better chance at suppressing a wildfire. Between early 2013 and June 2024, DWR and its local partners have treated or retreated more than 2,500 acres of vegetation.

 

DWR’s Floating Classroom program returned this fall, offering free educational rafting tours on the Feather River to local schools and public members. The Floating Classroom program takes participants through Feather River spawning habitat while scientists with DWR and Pacific States Marine Fisheries Commission provide information on Chinook salmon conservation efforts, ongoing and planned research, restoration and monitoring projects, and fisheries management activities supported by DWR’s State Water Project (SWP). This year’s program provided free education to more than 900 local students, parents, and teachers, and over 650 community members.

 

Annual Chinook salmon spawning activities at the Feather River Fish Hatchery in Oroville were also completed. The Hatchery collected enough eggs to meet its normal production goal of 2 million spring-run fingerlings and 6 million fall-run fingerlings, with additional eggs collected to increase production this year. Another 1 million spring-run and 6 million fall-run Chinook salmon will be produced to address declines in Central Valley Chinook salmon populations during recent years. Chinook salmon fingerlings raised at the Hatchery will be released in the Feather River and San Francisco Bay between March and June to support inland and ocean populations. The Feather River Fish Hatchery is a SWP facility built in the late 1960s by DWR to mitigate impacts on fish migration resulting from the construction of Oroville Dam. DWR owns and maintains the facility and provides funding to the California Department of Fish and Wildlife (CDFW) to perform spawning, rearing, and stocking operations.

 

DWR looks forward to initiating and completing more projects in 2025 at the Oroville-Thermalito Complex. The Lake Oroville Community Update will continue to share news and information with the community. 

 

Oroville Recreation

The Lake Oroville Visitor Center will close all day for the Christmas and New Year holidays. Visitors may still access nearby trails during the holiday closures.

 

The Spillway Day Use Area and Boat Ramp will be open from 6 a.m. to 6 p.m. on Christmas Eve and Christmas Day. Winter hours for the Spillway Day Use Area are in effect through April 30, 2025, with the recreation area open daily from 6 a.m. to 8 p.m.

 

Upstream migrating fish totals through the Feather River Fish Monitoring Station between Jan. 1 and Dec. 13 are:  

• Spring-run Chinook salmon (March 1 through June 30): 7,152
• Fall-run Chinook salmon (July 1 through present): 40,163
• Steelhead: 1,797

 

Current Lake Operations

Lake Oroville is at 791 feet elevation and storage is approximately 2 million acre-feet (MAF), which is 59 percent of its total capacity and 110 percent of the historical average.

 

Feather River flows are at 800 cubic feet per second (cfs) through the City of Oroville with 950 cfs being released from the Thermalito Afterbay River Outlet (Outlet) for a total Feather River release of 1,750 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 12/19/2024.

 

DWR wishes everyone a happy holiday season.

The Lake Oroville Community Update will return on January 10, 2025.

 

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Know someone who would like to receive Community Updates? They can email their request to oroville@water.ca.gov.