This past month the Engineering Contractors’ Association along with other construction groups showed up in support of a Los Angeles County project to remove sediment that had been building up behind Devil’s Gate Dam on the Arroyo Seco waterway in Pasadena.

Built in 1920, at the narrowest place on the often dry riverbed, the dam was originally designed to control flooding. It was named Devil’s Gate Dam for the demon-like face of a horned figure in the natural rock outcropping next to the structure.

Devil’s Gate flood waters

Over nearly 100 years since the dam was built the forces of erosion in the nearby San Gabriel Mountains have packed the reservoir behind the concrete structure to near the bursting point.

The L. A. County Department of Public Works has been working on a plan to both save the dam and remove the sediment buildup for the intervening 97 years.

The original plan, approved in 2014, was to remove 2.4 million cubic feet of debris, restoring the flood control basin to its original capacity. Environmentalists and neighbors rose up in opposition over noisy trucks and “wildlife habitat.” The city of Pasadena wanted the sediment removal effort nearly halved to 1.4 million cubic feet.

That’s where things stalemated until Fifth District Supervisor Kathryn Barger came up with a compromise through discussions with what she called “…our concerned community members, environmental groups and the city of Pasadena who have participated in discussions with me and county departments over many months.”

The compromise proposal, to remove 1.7 million cubic feet of material, along with sweeteners for the opponents such as full funding for the Arroyo Seco Ecosystem Restoration Study, watershed improvements, and an early warning system for similar flood control facilities across the county was approved by a unanimous vote of the Board of Supervisors.

ECA was there to support the proposal as a way of getting something done before the dam actually collapsed under the weight of sediment and was overtopped by rising flood waters. It also may mean job opportunities for our members.

We thank Supervisor Barger for skillful efforts, one of the many reasons we proudly supported her election to the board.

By Wes May, ECA Executive Director
Email: [email protected]