David Wilson, PE, CFM Snohomish County Public Works Surface Water Management

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1 Through the FEMA Hazard Mitigation Assistance Programs Background and Review of recent Snohomish County experiences David Wilson, PE, CFM Snohomish County Public Works Surface Water Management Stillaguamish Technical Advisory Group - March

2 To share information on Snohomish County s experience with mitigation of flood hazards. To discuss techniques for meeting FEMA criteria for funding under the Flood Mitigation Assistance, and Hazard Mitigation Grant programs offered. To compare and contrast strategies for dealing with flood hazard conflicts with the built environment. 2

3 Third largest county in Washington State by population, over 772,501 citizens (2016 OFM estimate) with most population in the SW corner near Seattle. Five major river systems: Snoqualmie, Skykomish, Snohomish, Stillaguamish, Sauk Rivers. 5.7% of county land area located in the flood plain. Joined the NFIP in the 1970 s, the community flood insurance study adopted in 1984, many older homes constructed without the benefit of flood information. 3

4 Snohomish County experiences a presidential disaster declaration about every 3-4 years, 15 have occurred since Between 1978 and 2017, the National Flood Insurance Program paid nearly $ 23.5 Million in 1,332 flood insurance claims within unincorporated Snohomish County. In 2016, the county had 152 properties that met FEMA s definition of repetitive flood losses. 41 properties have been mitigated with 10 of them located within the Stillaguamish Basin. 4

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6 Community property acquisition: Acquire home, demolish it, decommission well and septic system, convert to open space with deed restriction. Home relocation: Move home to an area outside or above the flood risk area. No action: Wait until the river floods the home and make a flood claim. 6

7 Basis for the County Elevation program is an action initiative from the 2004 Stillaguamish River Comprehensive Flood Management Plan. Longer history of privately funded home elevations particularly in the Snohomish and Stillaguamish coastal/ estuarine areas. After flood events such as the January 2009/ Fall 2015 floods, demand intensifies with nearly 20 inquiries a week as recovery ramps up. First project sponsored by Snohomish County was a Historic home built in

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12 Snohomish County uses a reimbursable contract. Owners are responsible for development of building plans, hiring/ directing contractor, obtaining permits. Cooperating citizens drawn from FEMA provided RL list, annual flood season brochure, response to phone and internet/ inquiries. Eight projects implemented in eight years, three homes currently under contract, beginning the plan preparation and construction process. 12

13 Property owners: May be overwhelmed by overlapping regulations, hiring/ managing a contractor, cash flow and liquidity during active construction are a barrier for low income families. Project costs: Completed projects vary in cost from as low as $ 55K to $ 230K over eight homes countywide since 2009 for estimated construction costs of $ 930K un- adjusted for inflation. Patience required: The typical home elevation project can take months from grant application development to the point of ground breaking by a general contractor. 13

14 Less controversial use of public financing as the community owns an asset at the end of the project. Purchase of high flood risk homes at market rates with FEMA funded relocation assistance in some cases. Chatham Acres near Darrington, 14 parcels acquired in , $ 1.8 Million (Nisqually Earthquake Recovery funds) for total of 28 acres of open space. 14

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17 Two Homes in The Jordon Trails plat at risk to channel migration and erosion One Home in the Indian Summer plat substantially damaged by Flooding One Home in the Cedar Lanes Estates One Home in the Blue Spruce Grove Plat One Home downstream of the Cicero Bridge with flooding and channel migration issues One home located in Silvana, behind the Viking Hall 17

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27 Two Homes in the Silvana Area One Home in the Terrace Falls Plat 27

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30 For projects proposed in the mapped flood plain; in August 2013 FEMA adopted programmatic nationwide thresholds of $175,000 for Home Elevations and $ 276,000 for Acquisitions. Local matching funds may be higher for sites without flood damage histories. For Channel Migration and head ward Mass Wasting hazards a historic erosion rate must be developed by a Qualified Professional. The erosion rate is then screened by the FEMA approved cost analysis software to determine eligibility of projects. 30

31 Develop a balanced take on code enforcement, and focus on long term outcomes as citizens value their privacy and can be slow to trust government With acquisition projects, develop good relationships with neighbors to maintain stewardship goals for each site after a buyout Many flood mitigation projects do not pan out, from scoping in a grant to implementation roughly a 50% success rate on implementation has occurred in the last five years in our experience managing projects 31

32 David Wilson, PE, CFM Snohomish County Public Works (425)

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