County of Marin - News Releases - Flood Control Review

For Immediate Release
March 24, 2015

Public’s Requests Lead to Flood Control Review

All ideas, including those eliminated in past, back on table in Ross Valley

San Rafael, CA – A full range of alternative flood control measures, including flood detention basins and ideas eliminated through the years, are being considered in a review of the Ross Valley Flood Protection and Watershed Program. A draft plan is expected to be completed by June.

A man speaks with a microphone in front of a group of people attending a flood control meeting.The Marin County Flood Control & Water Conservation District has initiated the review to analyze the proposed measures that would help prevent flooding in Zone 9, comprised of the chronically vulnerable Ross Valley communities of Fairfax, San Anselmo, Larkspur, Ross, Kentfield and Greenbrae. The goal will be to arrive at the most viable and publicly accepted plan for flood reduction in areas near Corte Madera Creek.

Alternatives will be laid out at an April 16 meeting Flood Zone 9 Advisory Board at San Anselmo Town Hall, 525 San Anselmo Avenue. The meeting starts at 7 p.m. and the public is invited to attend and provide input.

“We have heard community members of the Ross Valley loud and clear in their desire for more information about the proposed measures to reduce significant flooding in Ross Valley, as well as opportunities to provide public input,” said Scott Lyle, Program Manager with the Flood Control District. “We look forward to working together with the community to arrive at a mutually-agreed upon plan.”

The review, to be led by CH2M HILL Engineers, is designed to revisit measures included in the district’s 2011 Capital Improvement Plan Study and put forth in its 10-Year Work Plan. It will include alternatives that have been brought forward by residents and eliminated after evaluation.

CH2M HILL Engineers is a global engineering and environmental consultant firm with offices throughout the Bay Area and extensive experience with flood program design and implementation. It was awarded the contract November 25, 2014, to conduct the review and plans to make its recommendations to the Flood Zone 9 Advisory Board on June 16. The public is invited to that meeting as well. The review results and recommendations will be incorporated into the upcoming County environmental review process on the watershed, a key milestone prior to project construction.

Five detention basin system is considered a critical element of the flood control plan, but the proposed locations of the basins remain under review. Using revised and comprehensive criteria developed with public input, the review will examine all proposed detention basin sites, including those previously considered but not carried forward and ones identified by the public or the consultant as potentially viable locations.

The review will include criteria to evaluate and rank the flood reduction elements. Initially, a subset of the measures will be applied as “fatal flaw criteria” to identify sites that would endanger the public or make flooding worse. Elements that are not eliminated by the application of the fatal flaw criteria will be combined to create alternative watershed-wide flood control plans that will then be ranked with public input.

Feedback is welcomed on the latest review documents, which can be found on the Ross Valley Flood Protection and Watershed Program website at E-mail input on the review criteria to Senior Civil Engineer Russ Eberwein at  Additional feedback will be requested regarding future stages of review to be made available on the website at a later date.

The Marin County Department of Public Works serves as staff for the Marin County Flood Control and Water Conservation District, which is overseen by the Board of Supervisors when it convenes as district board.

Ross Valley Flood Protection and Watershed Program is a collaboration between the County government and the municipalities of Fairfax, Ross, San Anselmo and Larkspur created after the devastating flood of 2005 that caused approximately $100 million in damage. The program goals are to reduce the risk of flooding using a watershed-wide approach; integrate environmental restoration features with the flood mitigation projects; and leverage funds obtained through the Ross Valley storm drainage fee to secure state and federal grant funding to study and construct publically-approved projects.


Neal Conatser
Capital Planning & Project Manager
Ross Valley Flood Protection & Watershed Program, Department of Public Works

3501 Civic Center Drive
Suite 304
San Rafael, CA 94903
(415) 473-2941
Email: Neal Conatser
Public Works website