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Arroyo Seco Foundation

News of the Arroyo


Devil's Gate Dam sediment removal project dealt a blow after environmental report deemed ‘deficient'





<b>February 15, 2017</b> - Judge James Chalfant ruled the County Flood Control District's Environmental Impact Report on their Big Dig program for Hahamongna Watershed Park deficient and set a hearing on March 23 to consider remedies.<b></b> -


Steve Scauzillo, San Gabriel Valley Newspapers


Pasadena Star-News


This Sept. 14, 2009 staff file photo shows the Devil’s Gate reservoir basin including the Devil’s Gate Dam and Hahamonga Watershed Natural Park in Pasadena. SGVN/Staff photo by Eric Reed/SVCITY/FILE

PASADENA >> A Superior Court judge ruling Tuesday has sent the controversial Devil’s Gate sediment removal project back to square one.

Judge James Chalfant agreed in part with the Arroyo Seco Foundation and the Pasadena Audubon that the Final Environmental Impact Report (FEIR) approved by the county in November 2014, was deficient. Without an adequate FEIR, the Board of Supervisor’s approval may be void.

“It does stop the project until they redo the EIR and get another approval from the Board of Supervisors,” said Mitchell Tsai, attorney for the plaintiffs.

Michael Simon, county counsel on the case, declined to comment. Kerjon Lee, spokesman for the county Department of Public Works, also declined to comment and said he did not attend the hearing.

The judge’s 29-page ruling said the county failed to consider the cumulative impacts on birds, other wildlife and rare plants living in the Hahamongna Watershed Park in Pasadena for a project that would remove 2.4 million cubic yards of sediment, dirt and plants using 425 trucks a day for five years. He also wrote the county used outdated numbers and was wrong to conclude that air pollution from those 425 diesel trucks would not have a significant effect on air quality and the health of nearby residents.

“The FEIR’s cumulative impacts is deficient as a matter of law,” wrote the judge in a tentative ruling. The judge said the county based its mitigation efforts, namely for every acre of riparian or nesting bird habitat destroyed, one acre would be restored, on inadequate science. For example, it reported on the effects of 50 bird species instead of the 206 species of birds in the area as reported by the plaintiffs, including the endangered least Bell’s vireo, a songbird on both federal and state endangered species lists. Nesting pairs have been spotted in the project zone since 2012.

Chalfant also required the county to submit additional evidence proving that a 1:1 mitigation plan is satisfactory, saying the environmental document’s conclusion that impact to biological resources would be less than significant “lacks substantial evidence.”

The county can submit new information and decide whether to do an amended EIR or a completely new EIR — a much more timely and expensive endeavor — by the next court date on March 23.

“Typically this requires a 3:1 mitigation and sometimes a 6:1 mitigation,” said Mickey Long, Pasadena Audubon member who supplied input for the case. Often, new trees do not survive, hence the reason for more than one acre of restored habitat. Additional acreage is a hedge against failure, he said.

However, the judge decided in the county’s favor on two other issues. First, Chalfant disagreed that a new EIR include a separate project planned by the county to pipe storm water from Devil’s Gate to Eaton Canyon spreading grounds in east Pasadena.

Also, Chalfant did not order the county to reduce the project’s scope, something the plaintiffs wanted. Instead, he said the scope of the project should be left up to the county and its engineers.

The county district’s engineers say removing the sediment is necessary to keep the dam operating efficiently and to protect Pasadena and South Pasadena homes downstream in the event of a major flood. The dam, located in Hahamongna Park, catches water and debris from a large watershed area north of the NASA/Jet Propulsion Laboratory in adjacent La Canada Flintridge.

The two groups have argued that the county neglected the dam for years and now want to do a massive sediment removal as catch-up. The groups want to see a small amount of sediment removed each year. A working group convened by the Pasadena City Council recommended taking 1.1 million cubic yards.

The area behind the dam has become a popular spot for migrating birds and nesting birds. It includes 41 plant species, part of the rare riparian woodland and mule fat thicket ecological communities

Built in 1920, Devil’s Gate Dam is the oldest in the county.




Arroyo Seco Foundation, PO Box 91622, Pasadena, CA 91109-1622 (323) 405-7326