In an effort to ensure air quality during work on the Devil’s Gate Dam Reservoir Restoration Project, LA County Supervisor Kathryn Barger directed the Department of Public Works to test tailpipe emissions from the dozens of trucks hauling sediment out of the Hahamongna Watershed Park, where the dam is located.

“In launching Phase II of our air quality strategy, I ordered this additional high level of truck emissions monitoring as an extra level of prevention to ensure trucks hauling sediment from the construction site are in full compliance with the project’s stringent standards,” Barger said in a statement issued Aug. 16. “Vital emissions data will be collected and necessary corrective actions will be taken. I want to ensure that community concerns are fully addressed and that every possible safeguard is in place to protect public safety and the environment.”

Currently, the county Flood Control District is using hundreds of truck trips a day to excavate more than 1.7 million cubic yards of sediment from the Devil’s Gate Dam reservoir, a job that is expected to take four years to complete.

Known as the Big Dig, the project has come under fire by residents of Pasadena and nearby La Cañada Flintridge. It has also been assailed by the Arroyo Seco Foundation (ASF) and the Pasadena Audubon Society (PAS), both of which filed a lawsuit to stop it.

A large amount of sediment has not been removed from Devil’s Gate 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 LA County Flood Control District, providing flood protection for the cities of Pasadena, South Pasadena and Los Angeles.

In June, Los Angeles Superior Court Judge James Chalfant postponed a trial over a lawsuit filed by the Arroyo Seco Foundation and the Pasadena Audubon Society.

Chalfant ruled the county did not provide enough time for people to comment on the project’s environmental impact report. Oct. 15 has been set for a settlement hearing.