Marin County Watershed Stewardship ProgramMarin County Watershed Stewardship Program

Marin County Department of Public WorksMarin County Department of Public Works

Countywide Watershed Program

The watershed program provides a framework to integrate flood protection, creek and wetland restoration, fish passage and water quality improvements with public and private partners to protect and enhance Marin’s watersheds.

Why A Watershed Approach? Why now? We have momentum and support from our partners and

the County.

The issues identified by the community aren’t going away so this program allows us to be ready when the economy recovers and new funding programs come on line.

Supports and guides protection and enhancement of significant natural resources

Ensures alignment with State and Federal resource agency goals which should support timely project implementation

Leverages funding to attract State and Federal sources

Dedicates staff to search for and pursue funding

Policy Advisory Committee: •BOS FC District Rep•City Council Reps•Flood Zone Advisory Board Reps•Water and Sanitary Board Reps

Technical Working Group:•Municipal Directors •Local, State & Federal Agency Reps •Watershed Groups •Homeowner’s Association Reps

Operations and Finance Committee: •City Managers & County DPW Director

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Board of SupervisorsFlood Control and Water Conservation District

Objectives Provide an increased level of flood protection Reduce on-going maintenance costs and impacts Develop projects that provide multiple benefits i.e

restoration and flood protection Ability to permit as a self-mitigating project Respond to sea level rise Opportunities to improve ecological benefits Ability to meet multiple partner agency objectives

Next Steps

Continued improvements to the website

Watershed-level planning Habitat Assessments Hydrology and Hydraulics studies Watershed Master Plans

Continued review of grants and other funding opportunities

Habitat Assessment

2009 Fish and Game creek assessments Goal is to translate their data into an

informative and accessible manner Spatial or GIS analysis is the tool

• Fish passage barriers• Pipelines and other infrastructure• Storm drain system• Restoration opportunities• Habitat features• Flow history and stream persistence• Other relevant information

Hydrology and Hydraulics Collecting field data including topography, rainfall, stream

flow, and sediment transport

Using the field data, a model is developed to show: How water moves in the creek Water depth outside the creek

How will the model be used? Representation of past and predicted storms Depict the footprint and elevation of flood waters Show the benefit of any proposed alternative Can be altered to include new information in the future

Hydrologic model development

Model is a predictive tool to test the effectiveness of various flood control measures

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1,000

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6,000

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12/30/056:00

12/30/0512:00

12/30/0518:00

12/31/050:00

12/31/056:00

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Total discharge

Out-of-channel discharge

In-channel discharge

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5,400 cfs

H & H Study outcomes

Understanding of the flood benefit and estimated cost for all proposed projects.Clear understanding of the current flood

impacts for a series of storm eventsModel will be a tool that quantifies the flood

impactShows the extent and depth of flooding

before and after for a given alternative or a suite of alternatives

Can be adapted for future conditions

For more information contact:Liz Lewis, Principal Planner 499-7226

Chris Choo, Senior Planner499-7586

www.marinwatersheds.org