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Pasadena Council approves Devil's Gate Dam sediment removal recommendations





<b>May 12, 2014</b> - Pasadena has taken a strong stand, telling LA County Flood Control District that it will insist on a sediment management program for Hahamongna Watershed Park that will emphasize reduced impacts and sustainability.


Lauren Gold


Pasadena Star-News


The Devil’s Gate reservoir basin including the Devil’s Gate Dam and Hahamonga Watershed Natural Park in Pasadena. Staff file photo

PASADENA>> The City Council unanimously approved a citizen working group recommendation for a revised plan for sediment removal at Devil’s Gate Dam.

The plan will be submitted to the Los Angeles County Flood Control District for consideration in the Devil’s Gate Reservoir Sediment Removal and Management Project. City Manager Michael Beck said he was confident that the county would take the city’s suggestion under serious consideration but stressed along with council members that the city would be forceful if necessary.

“I’m optimistic we will be able to negotiate effectively with the county to accommodate the proposal,” Beck said.

The county completed a draft environmental report on the project in October that proposed several different proposals ranging between creating 3.6 and 4 million cubic yards of storage space by removing 2.4 to 2.9 million cubic yareds of debris over five years. The proposal alarmed many residents and council members as a project that could destroy the cherished Hahamongna Watershed Park if not properly managed. To ensure the city had a strong voice in the process, the council created the six member working group in December to study the issue in depth and submit a more reasonable proposal.

The working group’s plan proposes that 2.5 million cubic yards of storage space be maintained in the dam, meaning that 1.1 million cubic yards should be removed over the next five year using low emission trucks during limited hours of the day, not including holidays and weekends. The proposal also suggests the county not remove sediment in the western portion of the dam area, which is a part of the park that many recreationists and animals use frequently.

“We came to a consensus and we think our report is thorough,” working group member Henreen Nunley said. “And I think you will have to look far and wide to find something better.”

Sediment was last removed from the dam area in 1994, and officials said the 2009 Station Fire contributed a significant amount of the debris that could cause a safety hazard in the flood channel if not removed.

The county’s final environmental report is due out in late summer and the project is scheduled to begin in 2015.

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Correction: A previous version of this story incorrectly stated the working group recommendations for sediment removal and incorrectly identified the proposed project area.

Lauren Gold
Reach the author at or follow Lauren on Twitter: @laurenkgold.




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