The Sacramento Metropolitan area is one of the most at risk areas for flooding in the United States due to its location at the confluence and within the floodplain of two major rivers. The 1997 Sacramento flood events revealed deep under-seepage on the Sacramento River, including in areas that were remediated to address through-seepage with shallow cutoff walls in the early 1990s.
Construction is set to begin this spring on three miles of levee improvements on the east side of the Sacramento River just south of the confluence downstream to the town of Freeport. The work will entail installation of various types of seepage cutoff walls, raises and berms within or adjacent to the levee prism.
This is the fourth major construction contract to address seepage and stability concerns with the levee between Old Sacramento and the Freeport Regional Water Intake Facility near Sacramento’s Pocket neighborhood. In 2020, construction crews installed nearly three miles of seepage cutoff wall along the Sacramento River East Levee, and a 400-foot-long seepage berm on the landside levee adjacent to Front St. In 2021, USACE contractors installed approximately 1.8 miles of seepage cutoff wall at four locations, including on both sides of Business 80/Highway 50 just upstream of Miller Park, on the south side of the little pocket, and on the north side of the big pocket. In 2022 there were two miles of improvements completed in the Big Pocket and erosion improvements just north of the Little Pocket. In total, the American River Common Features 2016 project is expected to construct approximately 9 miles of slurry cutoff walls along the Sacramento River East Levee, and up to 10 miles of erosion protection at a number of locations.