Devil’s Gate Dam Sediment Removal Completed Early

The Los Angeles County Department of Public Works announced that sediment removal involved in the Devil’s Gate Restoration Project was expected to be completed by Tuesday.

The planned four-year effort to remove 1.7 million cubic yards of sediment from the Devil’s Gate Dam Reservoir is concluding a year earlier than expected. 

Contributing factors included efficient sediment removal and favorable weather conditions. 

“Los Angeles County Public Works would like to thank the local residents, the Community Advisory Committee, local stakeholders, neighbors, and businesses in the communities of Altadena, La Cañada, Pasadena, and Sun Valley for their continued collaboration and patience through to the completion of this project,” according to a statement issued by the department. 

Public Works team members will continue to perform finishing construction activities within the reservoir through November. The habitat enhancement component of the project will continue through fall 2022.

Supervisor Kathryn Barger announced earlier this month that the project was all but completed. 

People living near the project site complained about air and noise pollution caused by the frequent truck trips in and out of Hahamongna Watershed Park to remove the sediment.

The project began in December 2017 to restore the facility’s flood control capacity to protect the communities downstream while establishing a permanent maintenance area and restoring native habitat in the surrounding 70 acres.

A large amount of sediment had not been removed from the Devil’s Gate reservoir since 1994 when workers hauled out 160,000 cubic yards of soil and debris. An additional 1 million cubic yards of soil and debris were dumped into the basin by the Station Fire in 2009, which burned more than 160,000 acres in Altadena, Pasadena, La Cañada Flintridge, and Acton.

Devil’s Gate is the oldest dam constructed by the L.A. County Flood Control District, providing flood protection for the cities of Pasadena, South Pasadena and Los Angeles.