LOS ANGELES -- The U.S. Army Corps of Engineers awarded a contract for construction services March 23 to Barnard Construction Company Inc., headquartered in Bozeman, Montana, for the Prado Dam Spillway Modification project.
The approximately $1.13 billion contract enables USACE and Barnard to complete the modifications to Prado Dam, which helps manage flood risk for about 1.4 million people and more than $200 billion in property and infrastructure between the dam and the Pacific Ocean.
The structure is considered a “dry dam,” with generally low water levels behind the reservoir. Its primary features include the main dam, consisting of a large earthen embankment, auxiliary dike, concrete outlet for controlled water releases and a wide concrete spillway to handle excess water flows.
The critical flood-risk management project combines two phases of the project into one.
The first phase is to address the potential failure modes that were identified in a dam safety modification study by constructing a labyrinth-style control structure to replace the existing spillway; demolishing and rebuilding all spillway chute walls and slabs; and connecting it to the earthen embankments. The new design provides a higher level of safety for the downstream communities.
The second phase of the project is to raise the spillway’s crest by 20 feet to match the elevation of the 2005 main dam embankment raise.
USACE is using a form of early contractor involvement, known as Integrated Design and Construction, that leverages both USACE’s and Barnard’s expertise to increase efficiency in project delivery, a key priority for delivering infrastructure projects faster and at a better value to the taxpayer.
Significant construction is expected to begin by the spring of 2027 and is anticipated to be completed by 2033. The dam will remain fully operational and continue to reduce flood risk during construction. USACE is working with surrounding communities to keep them informed and minimize the impacts during construction.
"Our ‘Building Infrastructure, Not Paperwork’ change initiatives are about delivering results by prioritizing our nation’s highest priority projects,” said Adam Telle, the Assistant Secretary of the Army for Civil Works. "At Prado Dam, we’re pairing smarter contracting with the innovative engineering of a labyrinth spillway to provide a higher level of safety for 1.4 million Americans. This is how the U.S. Army Corps of Engineers will continue delivering on President Trump’s vision for better infrastructure for our great nation.”
About Prado Dam
Prado Dam is a flood-risk management project owned and operated by the U.S. Army Corps of Engineers Los Angeles District on the Santa Ana River near Corona, California. Since its completion in 1941, the dam has effectively managed flood risk for the region, while its reservoir also provides for recreation and water conservation. The current safety modifications are necessary to modernize the dam and address challenges that have emerged over decades, such as regional urbanization and increased runoff.
To learn more about Prado Dam and Reservoir, visit https://www.spl.usace.army.mil/Missions/Asset-Management/Prado-Dam/.