Fact Sheet

Investigations - Imperial Streams Salton Sea, CA

U.S. Army Corps of Engineers, Los Angeles District
Published April 16, 2024

LOCATION AND DESCRIPTION: The feasibility study area includes the Salton Sea, its tributaries, the playa and surrounding areas suitable for restoration. Salton Sea is a shallow, saline, terminal lake sustained by agricultural discharge from the Imperial Valley. The lake provides significant habitat for birds, an estimated 400 species rely upon the lake, as well as habitat for several state and federally listed species. The sea is naturally receding due to evaporation and recent water transfers causing an increase in salinity and concentration of pollutants.

AUHORIZATION: Resolution of the U.S. Senate Committee on Environment and Public Works, 114th Congress, 2nd Session (April 28, 2016)

IIJA ACTIVITIES: See activities in FY23 / 24.

FY2024 PLANNED ACCOMPLISHMENTS:  Carryover funds will be used to continue feasibility phase

ISSUES AND OTHER INFORMATION: The study scope will require more than $3M and 3 years to complete. Drivers of an extended study duration could include: additional activities to reduce uncertainty about future hydrologic conditions; robust community outreach activities and translation services; extensive public comment from highly engaged stakeholders; and potential policy waivers to include allowing quantification of restoration benefits and construction of restoration projects on lands owned by other federal agencies. The study team explored options within $3M and 3 years but a suitable result could not be expected from that scaled down effort.

As of 26 Jan 2024


Estimated Federal Cost           $1,700,000
Estimated Non-Federal Cost        $1,500,000
Total Estimated Project Cost         $3,200,000
Allocation thru FY22              $1,500,000
                                                                                                                                   Presidents Budget FY24                       $0                                                                                                                                                                                                         Approved IIJA FY24                        $0
Workplan for FY24                     TBD
President’s Budget for FY24            TBD
Balance to Complete After FY24     200,000

Congressional Interest: Senators Padilla (CA), Butler (CA), Kelly (AZ), Sinema (CA), and Representatives: Ruiz (CA-25), Calvert (CA-41), Issa (CA-48) and Lee (NV-3)


The study team held two NEPA (National Environmental Policy Act) public scoping meetings on 18 May, and two focused scoping meetings with the community and non-government organizations. After the public comment period ending on 6 June, the study team refined three different study courses of action (COA) that each entailed a unique scope, schedule, and budget to accomplish the feasibility study.

Of the three COAs, the study team recommended COA 2 with non-federal sponsor (NFS) support, which would retain a final array of approximately 4-6 alternatives. COA 2 would take 8 years and $15.847 million to finish the study. As part of the environmental analysis, the study team would utilize the Audubon Society’s ecological model that was developed specifically for the Salton Sea. The Audubon model accurately represents the unique habitats and conditions of the study area. For the engineering analysis, the modeling approach would utilize hydrodynamic (AdH) and hydrology (GSSHA) models in conjunction with a collaborative future-hydrology workshop.


USACE South Pacific Division leadership concurred with the proposed COA 2 by signing the Vertical Team Alignment Memorandum (VTAM) on 21 November. However, current interpretation of the Bipartisan Infrastructure Law (BIL), which is funding the study, requires that studies “initiate and complete” with BIL funds. As there is no additional BIL funding available, the study team collaborated with the Non-Federal Sponsors on how to best carry out the study while remaining policy-compliant with BIL.

Therefore, the study team revised the original COA 1, which accomplishes a 3-year study with $3 million (3x3), as COA 1.3. Still adhering to the 3x3 cost and duration, COA 1.3 proposed performing technical work that would be documented in a technical report and could be used in a future study. The technical work to be carried out under this COA could align with COA 2, but when funds are exhausted a report would document the work completed. This approach would not result in an implementable plan. The future hydrology workshop would be the highest priority item to complete under this COA because understanding the hydrology is a critical piece of any Salton Sea study.  If there are additional funds after executing the workshop, other priority analyses would be hydrologic modeling, documentation of existing and future conditions, and approving the Audubon ecological model for one-time use.

The study team is preparing for a future hydrology workshop in April 2024. The study team is working together with subject matter experts in the fields of hydrology, climate, biology, agriculture, and water and land use policy to develop a hydrologic and hydraulic model of the Sea.​ On March 8, FY24 budget passed and included a legislative fix on the study’s BIL funding limitations. The study can utilize non-BIL funds. The study team briefed Major General Graham on 10 April and advocated for a 3x3 exemption for additional funding and schedule length. Contingent on exemption approval, the study team will request additional funding through future budget opportunities.



Congressional Liaison