The deadline is today, Sept. 7, to submit comments regarding the recirculated portion of L.A. County’s Devil’s Gate Sediment Removal and Management Project plan. Still, opponents hope residents continue to contact officials with concerns about the project, which seeks to remove 2.4 million cubic yards of sediment from the reservoir.
The Arroyo Seco Foundation and the Pasadena Audubon Society filed a petition in court in 2014 challenging the Final Environmental Impact Report regarding what they call “The Big Dig.”
This April, L.A. Superior Court Judge James Chalfant temporarily halted the project and ruled that the Department of Public Works needed to modify its EIR before it could move forward with its plan, which is aimed at maintaining adequate downstream flood protection.
The judge asked the Flood Control District to provide evidence to support a 1-to-1 mitigation ratio in regard to biological resource impacts and that it find ways to reduce cumulative impacts.
Chalfant also required construction contractors to use only trucks that meet the EPA’s emissions standards for Model Year 2010 or later. (Those trucks are expected to make as many as 400 daily trips along segments of Oak Grove and Berkshire Drives while the project is ongoing.)
The Arroyo Seco Foundation’s Tim Brick said that even with those alterations, the scope of the project remains too large. He and others advocate for the plan proposed by the Devil’s Gate Dam Sediment Working Group and approved by the City of Pasadena, which suggested the county remove only 1.1 million cubic yards of sediment, which they say also creates sufficient reservoir capacity.
But according to the revised EIR, L.A. County’s Flood Control District maintains a mandate that Devil’s Gate Dam keep capacity for two “design debris events,” or about 4 million cubic yards, less than is currently available.
Storms in 2010 that followed the previous year’s Station Fire poured approximately 1.3 million cubic yards of sediment into the reservoir, increasing the risk of serious flooding with less than one design debris event.
Don Bremner, chair of Hahamongna Watershed Park Advisory Committee, said members of the L.A. County Board of Supervisors, including Kathryn Barger, should consider the low probability of two design debris events — often referred to as 50-year storms — hitting the area.
“When was the last time we had a 50-year storm? In 1969?” Bremner said. “We may bet on another one someday, but we’re going to get two of them in one year?”
Bremner and other members of the working group would prefer to see a slow, steady, surgical approach to sediment management, they said.
“The only concession [the county] made to sediment management is to establish a permanent waste zone of 50-70 acres where they’re going to remove sediment over and over on an ongoing basis,” Brick said. “There’s not going to be any sensitivity to habitat, and we’d like to see them have a surgical approach to the habitat, maybe move around a little bit so they wouldn’t destroy one zone over and over again.”
Brick and his colleagues are not impressed by the mitigations offered in the recirculated EIR, either.
“They came back and said, ‘OK, we’ll use 2010 trucks [instead of 2007 trucks],’ but they didn’t consider electric trucks or natural gas trucks,” said Brick, who said he counts 17 schools within a half-mile radius of the project. “That’s thousands and thousands of students, young people who are going to suffer from this project.”
He and Bremner both suggested that the county establish 5-to-1 habitat mitigation ration instead of the current 1-to-1 plan.
“Not all of those plants are going to grow,” Bremner said.
“After thinking about it for an awfully long time, it boils down to an argument about how to manage the sediment in Devil’s Gate Dam,” Brick said. “We’re not against the sediment management portion — we’re for it, but it should’ve started 20 years ago. If they’d started 20 years ago, or even if they’d started seven years ago, we wouldn’t have a problem at all now.
“If they’d have gone slow and steady, removed 200,000 cubic yards a year, they could be done by now.”
Neither Judge Chalfant nor the county supervisors have yet been persuaded that the county’s plan is, in fact, too aggressive. Except for the specific mitigation requirements the Department of Flood Control has sought to address in the recirculated EIR, the court found the remainder of the Final EIR in compliance with the California Environmental Quality Act.
Following the close of the comment period this week, written responses will be prepared and considered by supervisors at a future hearing.
Final Comments Due on Devil’s Gate ‘Big Dig’ Challenge
