Notice
Sediment removal at the reservoir now takes place Monday through Saturday. West Fork Road is closed to all vehicles. Pedestrian and cyclist use is ok on Saturdays, Sundays and holidays. Please watch for any work-related traffic.
West Fork Access Road
Due to potential safety hazards because of the Bobcat Fire, the U.S. Forest Service has prohibited public use or access of the West Fork Access Road.
Forest Order No. 05-01-24-02 West Fork Road Closure Map.
Coordination with Regulatory Agencies
While the Cogswell Reservoir Post-Fire Emergency Restoration Project is an emergency project, Public Works will ensure the project complies, and in some instances exceeds, regulatory requirements typically enforced on non-emergency projects. Public Works is partnering with the agencies below to ensure measures are taken to protect the public, recreational resources, wildlife, habitat, and water quality to the extent possible.
- Regional Water Quality Control Board (RWQCB) – Coordination with RWQCB to implement measures to protect water quality and aquatic resources. Restoration of the SPS will be implemented per a plan reviewed by RWQCB. A Section 401 certification has been issued by RWQCB.
- United States Forest Service (USFS) – Coordination for continued use of Cogswell Sediment Placement Site (SPS) and revegetation of the SPS at the end of the Project per a plan approved by USFS.
- United States Army Corps of Engineers (USACE) – Coordination for impacts to Waters of the United States. A Section 404 permit will be issued by USACE.
- California Department of Fish and Wildlife (CDFW) – Coordination with CDFW to implement measures that protect wildlife and habitat. Restoration of the SPS will be implemented per a plan reviewed by CDFW.
Emergency Declarations
On October 13, 2020, the Los Angeles County Board of Supervisors passed a motion instructing Los Angeles County Public Works to take immediate action to repair and restore facilities affected by the Bobcat Fire. This includes the removal of sediment from major dams and reservoirs such as Cogswell Reservoir. In accordance with the Board of Supervisors’ motion, Public Works has proposed a three-year project to remove 2.0 MCY of sediment from Cogswell Reservoir.
In addition to the emergency declaration by the Los Angeles County Board of Supervisors, the Bobcat Fire was also declared an emergency by the federal government and the State of California. These emergency declarations can be found in the Resources section.
Construction Schedule
Spring 2021 – Spring 2024
2 months each year
Spring 2021 – Fall 2024
4 years
Spring 2021 – Fall 2024
4 years
Fall 2021 – Fall 2025
5 years
Reconstruct access ramp to Cogswell Reservoir. Portions of the access ramp may need to be reconstructed each year.
The access ramp will connect the reservoir to Cogswell Sediment Placement Site (SPS). The access ramp will not interfere with the West Fork Road.
Remove 2.0 million cubic yards of excess sediment, which will enable the County to meet and maintain acceptable flood control standards.
Place material at Cogswell SPS, located adjacent to Cogswell Reservoir. The U.S. Forest Service has approved the use of Cogswell SPS for the placement of sediment removed from Cogswell Reservoir.
Erosion control measures will be implemented at the SPS following each work season.
Revegetation of the finished slopes of the SPS will occur at the conclusion of the project. The revegetation plan will be approved by the U.S. Forest Service.
Site Plan
