PRADO DAM SAFETY MODIFICATION - FACT SHEET
AUTHORIZATION: Flood Control Act 1936, Public Law 74-738. Modified by Flood Control Act of 1938, Public Law 75-761
PROJECT TYPE: Flood Risk Management, Dam Safety Modification Project
ABOUT
Prado Dam is a Dam Safety Action Classification (DSAC) 2 project, which is defined by ER 1110-2-1156 as "High Urgency" where failure could begin during normal operations or be initiated as the consequence of an event and the likelihood of failure from one of these occurrences, prior to remediation, is too high to assure public safety or the combination of life and economic consequences with probability of failure is high. The Dam Safety Modification Study cited foundation seepage w/ backward erosion piping at the central & west embankments and overtopping from the probable failure mode analysis event and recommended this project to address that potential risk.
KEY CONSIDERATIONS
Prado Dam provides flood risk management to 1.4 million residents and property valued at more than $200 billion across 29 cities in Southern California. Prado Dam is designated as a Dam Safety Action Classification (DSAC) 2 (very high incremental risk) project.
The U.S. Army Corps of Engineers awarded the Prado Dam Safety Modification Integrated Design and Construction Base Contract in April 2025. The base contract includes preconstruction services and early work items.
The project delivery team has advanced the design to a 95% maturity, awarded a contract for Quality Assurance laboratory improvements, and continued environmental coordination.
The Fiscal Year 2026 Interior and Environmental Appropriations Act provided authority to utilize incremental contract funding, this will allow the project to award the construction option with funds on hand.
Construction of Prado Dam and Reservoir was completed in 1941. It is operated by the U.S. Army Corps of Engineers, Los Angeles District, and is a central element of the Santa Ana River Basin flood risk management system. It provides incidental water conservation benefits and further reduces flood risk for more than 1.4 million people and over $200 billion in property across 29 cities in Southern California. The Dam Safety Modification Study (DSMS) approved by the Dam Safety Oversight Group in June 2022 designated Prado Dam as Dam Safety Action Classification 2 - "very high incremental risk." This is primarily due to loss of life consequences resulting from potential failure due to overtopping of the embankment low spot, and failure caused by spillway erosion. The project's aim is to design and construct the risk reduction measures identified in the DSMS to reduce the overall risk of failure, potential loss of life, economic consequences, and environmental effects.
STATUS
The base contract for preconstruction services and early work items for the spillway modification was awarded April 14, 2025, ($31,175,954) and the demonstration section contract modification was awarded on December 17, 2025 ($36,185,336). On January 23, 2026, the President signed the Interior and Environmental Appropriations Act authorizing incremental funding for the project.
The construction contract is scheduled to be awarded by March 23, 2026, with the first increment utilizing the Incremental Funding Clause. The current working estimate for the project is $1.646 billion Construction General for dam safety and $140 million BBA-18 Supplemental funding for the Raise portion.