Posted on May 20, 2026
Completion of Lower American River Contract 3A in 2025 marked a significant milestone for the American River Common Features program, supporting flood risk reduction in one of the nation’s most at-risk regions for catastrophic flooding.
The LAR C3A project now provides improved flood protection in an area that came close to failure during the 1986 flood event. During that storm, erosion reached nearly to the top of the levee upstream of the Interstate 80 bridge, and officials determined the levee was within hours of catastrophic failure had the rain continued.
This May 5, members of the U.S. Army Corps of Engineers Sacramento and St. Paul districts joined nonfederal sponsor representatives for an inspection of the project following its first winter flood season.
“Contract 3A was one of the most technically and logistically complex reaches within the American River Common Features program. It required close coordination across multiple agencies and stakeholders while working in tight spaces and navigating numerous obstacles and restrictions,” said Kevin Lee, project manager with Sacramento District.
Team members from St. Paul District led the design and implementation of the erosion protection features, leveraging expertise and additional staffing from across the nation to address a critical infrastructure project.
The team evaluated revegetation efforts and overall project performance, including the establishment of native riparian vegetation such as trees, shrubs, grasses, herbaceous perennials*, and wildflowers including the California poppy. Team members also discussed lessons learned from the project’s design and construction.
Contract 3A featured approximately 2,300 feet of levee improvements along the south bank of the Lower American River near the Business Interstate 80 bridge in Sacramento. Project team members designed the site to reduce flood risk and meet regional erosion protection requirements, while supporting vegetation growth to replace habitat impacted by construction of the levee improvements.
Construction crews placed more than 50,000 tons of rock and implemented erosion control measures, tree protection efforts, revegetation work, and instream woody material installation. Crews fastened trees in place to create habitat for juvenile salmon and other fish species during winter flows, and planted vegetation in and above the rock erosion protection structures to support the growth of dense stands of trees and shrubs.
“It’s exciting to come out here and see how the completed project is protecting this stretch of levee and the wildflowers already growing along the soil-filled rock we placed last year,” said Ben Nelson, project manager with St. Paul District.
Crews will complete revegetation plantings by the end of May 2026; however, project teams will actively maintain the site by providing temporary irrigation until vegetation becomes established. The team will also provide weed control for a few years in order to allow the native vegetation to colonize the site and crowd out weedy invasive plants.
The project involved coordination among the Sacramento District, St. Paul District, Caltrans, the City of Sacramento, and Union Pacific Railroad. The St. Paul District has supported Sacramento District flood risk reduction efforts since 2019.
*Herbaceous perennials are plants that live for multiple years but do not become woody.
