19 September 2025 - Update on Sacramento Weir Expansion Construction
The U.S. Army Corps of Engineers identified vertical settlement that exceeded the design tolerances at the Sacramento Weir Expansion’s north abutment wall in early 2025 and is designing a solution to address it. The north abutment wall is one of the 26 supports for a future bridge along the overall Weir Expansion Construction project. None of the other constructed features are experiencing movement issues. Addressing the unexpected movement is expected to delay project completion by about one year, but the current Sacramento Weir remains fully operational and there are no impacts to public safety.
Why Did This Happen?
Large, complex infrastructure projects often require adjustments due to real-world conditions that may not align with initial predictions. While we conduct subsurface investigations and analyses following industry standards and best geotechnical practices, unforeseen variations can still occur. To account for this, USACE includes cost and schedule contingencies. While we estimate a year delay, we’re confident this fix will stay within budget contingency.
At the north abutment, the underlying soil has responded in a manner that differs from the original design assumptions. We are performing additional subsurface investigations and installing instrumentation to better understand the slope soil movement so we can rebuild the abutment.
North Abutment Wall Timeline and Next Steps
- January - February 2025 – Routine monitoring of the north abutment. Movement remained within anticipated design tolerance.
- March 2025 – Movement exceeded tolerance limits, prompting evaluation.
- Spring–Fall 2025 – Engineers have been studying the issue and designing an appropriate solution.
- 2026 – Finalize cost estimate and construction schedule and begin corrective work.
- 2027 – Complete corrective work.
_________________________________________________________________________________
September 8, 2025- Update on Sacramento Weir Expansion Construction
The Sacramento Weir Widening construction project is well underway after starting in July 2023. The project construction is continuing year-round but is weather dependent. Primary activities since July 2023 include:
- Earthwork activities for the new North Levee setback, Old River Road embankment, and County Road 126 embankment.
- Pile Driving Rigs will be onsite in 2026 to drive 20-inch diameter steel pipe piles at the North Abutment and will serve as the northern extent of the weir and bridge.
- Dewatering system was installed which includes a network of white piping near the southern end of the project and is conveying water from groundwater pumps to allow for excavation activities below the groundwater level.
- Vehicle Bridge expected to be completed by early 2027. Traffic control detour will remain in place until the vehicle bridge is completed along Old River Road.
- Fish Passage Structure concrete placements have been completed for the fish ladder and riprap placement is underway for the fish passage channel. Fish Passage Phase 2 project features were completed in 2024 including modifications to the Sacramento Weir stilling basin to address fish stranding, completion of a new rock-lined channel, and completion of a new earthen channel that connects to Tule Canal.
Sacramento Weir Widening Draft SEIS/SEIR Virtual Public Meeting
August 19, 2020
Notice of Availability
Draft SEIS/SEIR Report
Draft SEIS/SEIR Appendices
Webinar Presentation Slides
Sacramento Weir Widening - Supplemental EIS/EIR Public Scoping
Virtual meeting held April 13, 2020. Public comment period closed on May 1, 2020. See presentation slides below:
