LOS ANGELES -- The U.S. Army Corps of Engineers Los Angeles District released the Report of Findings from its four-year Los Angeles County Drainage Area Project Disposition Study, which determined federal interest continues to exist in the federal project and, therefore, disposition cannot be recommended.
The Los Angeles County Drainage Area, or LACDA, is a comprehensive system that includes all flood-risk management features along the LA River and its tributaries that work in concert to drain the watersheds within LA County. The LACDA Project consists of flood-control and other features authorized by Congress within the LA River watershed, providing critical flood-risk management for approximately 10 million LA County residents.
The purpose of the study, which the LA District conducted under Section 216 of the Flood Control Act of 1970, was to determine whether continued operation and ownership of the LACDA by USACE is in the federal interest. The study, which concluded in May, determined the LACDA Project continues to meet its authorized purpose and provides significant, effective flood-risk management for the Greater Los Angeles area, along with significant economic and public benefits.
The various segments and features within the LACDA Project work together as an inseparable, interconnected system to provide flood-risk reduction and management benefits to the Greater Los Angeles area. Deauthorization of individual LACDA features would impact the ability of USACE to efficiently address emergencies and natural disasters, as well as during routine water management operations.
The channels within the LACDA Project are crucial to the safe passage of flood waters. Safety and operability of the overall LACDA Project and flood-risk management within the adjacent downstream communities is reliant on continued USACE management of releases from the federal dams in the LACDA Project, including associated channels.
Additionally, USACE prioritizes Operations and Maintenance work in the LACDA Project, with an emphasis on safety and operability of the flood-risk management system.
In fiscal year 2023, the Corps awarded a $13.5-million invasive species and sediment management contract for the Glendale Narrows. Work will consist of excavating 100,400 cubic yards of sediment and non-native vegetation as part of a multi-year plan to restore the as-built capacity of the soft-bottom section of the Los Angeles River.
Work in 2024 includes:
- Removal of concrete damaged from recent rain events downstream of Los Feliz Boulevard
- Debris removal and cleanup from more than 100 homeless encampments
- Monitoring 35 additional encampments for flood risk (notifying agencies to help move people out of harm’s way in the event of a storm)
- Removal of sediment on concrete surfaces of the channel
- Disposal of non-native vegetation on a weekly basis
- Inspection and assessment of 38 storm and subdrain pipes, and,
- Removal of graffiti along 250,000 square feet of the channel on an annual basis.
During recent unprecedented rainfall events, including Hurricane Hillary, USACE and the LA County Department of Public Works were in close coordination to manage the excess flood waters, capture storm water runoff and coordinate early notices to local agencies for public safety. This allowed for timely evacuation of channels prior to major storms, preventing flood-related drownings in the channel during the recent winter storms of 2023 and 2024.
“The strong relationships we’ve built over the years with our local and state partners are integral to the U.S. Army Corps of Engineers’ mission in the Los Angeles District area of operations,” said Col. Andrew Baker, U.S. Army Corps of Engineers Los Angeles District commander. “Our teamwork with the LA County Department of Public Works is one of the biggest factors in our success as we continue to provide flood-risk management to ensure the safety of the millions of people who reside here.”
The full Los Angeles County Drainage Area Project Disposition Study Report of Findings is available at https://usace.contentdm.oclc.org/utils/getfile/collection/p16021coll7/id/26162. Questions and comments can be submitted by emailing LACDADS@usace.army.mil. Information on public meetings and additional opportunities to provide feedback will be posted at www.spl.usace.army.mil/Missions/Civil-Works/Projects-and-Studies/Los-Angeles-County-Drainage-Area-Disposition-Study/.