The Devil’s Gate Dam sediment removal project, also known as the Big Dig, is expected to involve hundreds of daily round trips by dozens of diesel trucks.
Trucks used in the Devil’s Gate Dam sediment removal project will begin rolling on Monday, May 13, a Los Angeles County official said this week — though that’s not etched in stone.
Steve Burger, assistant deputy director of the L.A. County Department of Public Works cited that date while speaking to The Outlook after he and other officials delivered a progress report Tuesday to a gathering at the La Cañada High School auditorium. Burger, who said he has been put in charge of the project known as the Big Dig, had said during the presentation that trucks would start hauling in “mid-May.”
“I said mid-May because obviously we’re adapting to the community’s concerns and working with all of that,” Burger said. He acknowledged that May 7 and May 6 previously had been announced as the start of the truck traffic and the new date could also be a “moving target” as the county continues to listen to issues raised by residents.
Burger did not specify such concerns, but during a question-and-answer session audience members asked about the testing of soil for the possible use of the herbicide Rounder, reducing the hours trucks are used and general traffic issues.
The project, whose first phase began in late November, is expected to include 425 daily round trips by approximately 95 diesel trucks through the intersection at Berkshire Place and Oak Grove Drive and onto the 210 Freeway in both directions. The haul trucks will meet model year 2010 emission standards, county officials said.
Sediment removal, set for May 13, is the project’s third phase and will take place from 7 a.m.-5 p.m. Monday through Friday — with hauling ending at 3:30 p.m. — and no work on weekends, holidays or during major Rose Bowl events. Removal is to take place April through November and from 2020-22.
In November 2017, supervisors approved a scaled-down project to remove 1.7 million cubic yards of sediment. Work started after a nine-year process that included feedback from local residents, environmental groups, the cities of LCF and Pasadena and the community of Altadena.
The initial process includes removing sediment behind the dam at Hahamongna Watershed Park to restore habitat and increase flood protection within the Arroyo Seco Watershed. In late November 2018, work to clear out vegetation and trees began.
The meeting was put together by LCF 4 Healthy Air, which includes La Cañada Flintridge and other area residents who plan to reduce daily health and safety hazards of the community affected by the project. The volunteer group began in November 2018 to respond to concerns about the impact of traffic and air quality on the approximately 3,000 children located within the project’s area, according to one of its statements.
Elizabeth Krider, LCF 4 Healthy Air co-founder and a La Cañada Unified School District parent, told the audience that the meeting was not the end of the group’s efforts to safeguard children and the rest of the community.
“The purpose is to not stop the project but to improve implementation and overcome the hazards that the project poses with 50 round trips per hour as the maximum sediment removal rate,” said Krider, who holds a Ph.D. in chemistry and has worked at Caltech. “Those will cause impacts to air quality and pedestrians.”
She said the LCF City Council would have a community plan set for public discussion at its regular meeting on Tuesday, May 7.
County Public Works community liaison Brittany Barker told the audience the massive project became necessary when 1.3 million cubic yards of sediment flowed into the watershed because of storms after the 2009 Station Fire.
The officials displayed slides to the audience showing their agreement with some terms of the LCF 4 Health Air project such as conducting a Periodic Smoke Inspection Program Test for all trucks; making sure check-engine lights are not on in any truck; and performing soil samples (which was done in late February; samples were found to be below risk-management criteria).
Officials said they will also start monitoring air quality in proposed locations around the site for NOx (oxides of nitrogen), black carbon, PM10 (particulate matter 10 micrometers or less), and PM 2.5 (particulate matter 2.5 micrometers or less) by next week.
School District Superintendent Wendy Sinnette said LCHS used consultants to evaluate its air quality for pollution levels indoors and outdoors on Monday and Tuesday to help monitor the project’s impact.
The high school currently has “standard-grade” air filters in place but will install “hospital-grade” filters in all classrooms and buildings by Monday, Sinnette said. More expensive “surgical-room grade” filters are being pursued, with a five-year total cost of $210,000, she said.
Sinnette added physical education courses this summer will move to a district office location on Cornishon Avenue for weeks three through five. For the 2019-20 school year, P.E. courses will move indoors on days where air monitoring indicates poor or unhealthful levels, she said. There is not a similar plan for after-school sports because they are “facilities dependent.”
Sinnette discussed the community safety — or immediate action — plan set for discussion at the City Council meeting this Tuesday. She said it would describe trigger events such as truck emissions, harmful air quality and more, with plans on how to address it.
Deputy Michael Cerveny from the Crescenta Valley Sheriff’s Station told the audience — with an emphasis on student drivers — to make extra time for travel because of the massive project, which will bring more truck traffic into the area.
During the Q&A, there was some disagreement with Krider’s comments that the action plan should be started as soon as possible so people can have “that sense of confidence” before the trucks start removing sediment.
“I’m going to respectfully disagree for a number of reasons,” Burger said. “There’s really a dire need to start this project. We’ve got some numbers to indicate we are doing good here,” he said, referring to a study he said environmental scientists recently performed. “I think the monitoring we’re doing and the traffic analysis will inform us and drive us toward better action. Our desire is to move forward. Holding up the project, I don’t see any value in that.”
Mayor Leonard Pieroni responded that the community needs to be prepared in case “we need to slow down the trucks or have less trucks or whatever it is.”
Flyers available at the meeting and shown during Krider’s presentation included recommendations on what people can do if they see smoke from a hauling truck, trucks idling longer than five minutes or being driven unsafely. She suggested people call the L.A. County Public Works hotline at (626) 458-2507.
Those who seek more information about LCF 4 Healthy Air may visit LCF4HealthyAir.org. For more information on the project, visit dpw.lacounty.gov/swe/devilsgate.
