Devil’s Gate Annual Maintenance to Begin
September 1, 2022
Over the last three years, Los Angeles County Public Works removed 1.3 million cubic yards of sediment from Devil’s Gate Reservoir. This allowed the Devil’s Gate Dam to regulate high runoff flows during the 2021-22 storm season to mitigate flood risk to communities downstream.
Public Works will now conduct its annual maintenance of the reservoir from September 1 to December 15 to prepare the facility for the upcoming storm season. The work will include clearing vegetation within the reservoir basin and excavating excess sediment that washed in during the past storm season. Additional time is factored for the erosion repairs along the side slopes and the re-building of a low-flow diversion and two low-flow channels along the side slopes that serve the two maintenance areas at the bottom of the reservoir.
We appreciate your patience as we continue to restore the reservoir’s flood protection capacity.
- The Hahamongna Watershed Park perimeter trail will remain open, but access into the reservoir will be restricted during working hours. Safety measures will be implemented for park visitors.
- Sediment hauling will occur Monday through Friday, 7 a.m. to 3 p.m. and work within the reservoir may continue until 6 p.m.
- No work will be conducted on weekends, holidays, or during major Rose Bowl events.
- Trucks entering the reservoir from the facility’s east entrance on Oak Grove Drive will be loaded with sediment, exit the west access ramp onto Oak Grove Drive, and head north to Berkshire Place for freeway access.
- Best management practices will be followed to protect air quality.
For more information and details regarding maintenance, please refer to the Annual Maintenance Plan.