A number of projects to improve the levees along the Yuba and Feather rivers are currently underway or are planned for 2020.
Included is work on the Marysville Ring Levee. Since the first phase was completed in 2013, approximately $84 million has been spent on the project, which, once completed, is expected to provide the city with a greater than 200-year level of flood protection.
The U.S. Army Corps of Engineers is overseeing the project and recently began a new phase in April. The current focus is on an approximately 2,900-foot section of the levee just south of the Fifth Street Bridge on the southwest of town.
“This phase of the MRL project (Phase 2A South) is being constructed to improve and strengthen the levee along the Feather and Yuba rivers and to further protect the city of Marysville and its critical infrastructure, which has experienced extensive and repetitive flooding in the past,” said Margaret Engesser, project manager for the U.S. Army Corps of Engineers.
The work consists of degrading a section of the waterside embankment to allow crews to get into the levee and construct a cutoff wall before reconstructing the embankment with an impervious slope blanket. The cutoff wall, which protects from through- and under-seepage, stretches approximately 2,622 feet. Phase 2A South is expected to be completed by October.
A total of three phases – or about 6,100 feet of levee – have been improved since work began. Once the current phase is completed, crews will still need to install cutoff walls in three different sections (Phase 2C, 2B and 3). Following that, the final phase will include connecting the installed seepage walls together in several different spots. The corps estimates the remaining work to cost up to $50 million.
The project is on scheduled to be completed by 2024.
West Feather River Levee
A $77 million project overseen by the corps is currently underway on the west Feather River levee between Tudor Road and Cypress Avenue in south Sutter County. The work is to repair a five-mile stretch of levee that was heavily damaged in the 2017 Lake Oroville spillway incident that led to emergency repairs being made.
The current work includes degrading the levee before installing cutoff walls as deep as 140 feet. About 90 percent of the work is expected to be completed this year, with the rest being completed in 2020. It’s largely being funded by federal dollars, or $50 million of the total, with the rest being split between state and local agencies.
Just south of where that work is taking place, the California Department of Water Resources, along with the Sutter Butte Flood Control Agency, is working to improve a mile-long stretch of levee from Laurel Avenue to Cypress Avenue. The work includes installation of a cutoff wall in the levee and is expected to be completed by the end of the year.
The project is estimated to cost about $10 million and is being funded through Proposition 1E funds, which made monies available for rural levee repairs. The state’s Flood System Repair Program has committed or used nearly $80 million so far on rural flood protection, said Dave Wheeldon, supervising engineer for DWR.
Lastly, just south of where that project is being done, the U.S. Army Corps of Engineers has plans to repair a 9,000-foot section of levee starting in 2020. The area is also where emergency repairs were needed back in 2017 during the high-water events to help stabilize the slope and address seepage issues.
The project is estimated to cost about $19 million and will utilize federal dollars – Public Law 84-99 – which was set up by the corps to help repair damages sustained during significant storm events on well-maintained levees. The federal program is expected to invest $150 million in levee repairs.
“This shows the value of the PL 84-99 program,” Wheeldon said. “One thing we’re really trying to stress is that we want to get as many Levee Maintaining Agencies to participate in the PL 84-99 program as possible because when we do have flood events, the corps is coming in and putting in $150 million worth of investments.”