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Lower San Joaquin River

The San Joaquin River Basin, Lower San Joaquin River, CA project will provide flood protection for the City of Stockton, CA.   There is significant risk to public health, safety, and property in the project area associated with flooding, with major flood events having occurred in 1955, 1958, and 1997. The project will include 23 miles of levee improvements and two closure structures, one at Fourteenmile Slough and the other at Smith Canal. The levee improvements include cutoff walls, deep soil mixing (seismic), a new levee, levee geometry improvements and erosion protection. Non-structural measures include nonstructural features, such as Comprehensive Flood Warning Emergency Evacuation Planning and Floodplain Management. The project is expected to provide benefits to 162,000 residents by improving Federal and local levees that provide flood risk management.  Flooding risk would be reduced to approximately 122,000 people, over 80,000 structures, and $28.7 billion in property . The project will also offer the area an estimated 83 percent reduction in expected annual property damage, while enhancing security at 486 critical infrastructure sites – 23 of which are essential to life-safety.  Total annual benefits of the project estimated at $345,024,000 and net annual benefits is $295,730,000. As of 2020, the expected cost of the project was estimated at approximately $1.3 billion.  The project would allow the local community to continue to meet both Federal Emergency Management Agency certification requirements and at least a portion of the State of California’s criteria for funding of Flood Risk Management projects, allowing for potential reduction in National Flood Insurance Program costs to the community. Project construction is currently anticipated to start in 2024 with completion in 2039.

Contact Information

For more information on the
Lower San Joaquin River project 
please contact us at the following:



Mailing Address:
U.S. Army Corps of Engineers,
Sacramento District
1325 J Street, Room 1513
Sacramento, CA 95814