King County Flood Control District Flood Risk Reduction Work Program and Accomplishments

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1 King County Flood Control District Flood Risk Reduction Work Program and Accomplishments Brian Murray Water and Land Resources Division April 26, 2016 Department of Natural Resources and Parks Water and Land Resources Division River and Floodplain Management Section

2 Presentation Overview Floodplain Management in King County: Past and Present Flood Risk Reduction Program Objectives Regulatory and Planning Context Partnerships to Reduce Flood Risks Accomplishments to Date Capital Project Prioritization Policies and Corridor Planning Flood Risk Reduction Strategies and Capital Projects by River System

3 3 Key King County River Engineering Activities and Dates 1899: Landsburg Diversion Cedar River 1906: White River Diverted (permanently in 1912) 1912: Cedar River Diverted to Lake Washington 1913: Tacoma Public Utilities Headworks Green R. 1914: Cedar River Masonry Dam 1948: Mud Mountain Dam White River 1962: Howard Hanson Dam Green River 1964: South Fork Tolt River Dam 1966: Sammamish River Channelization 1930s-1970s: 500 levees & revetments constructed 3

4 Ecomomic Impacts of Flooding 32,000 Floodplain Residents 65,000 jobs $3.7 Billion in total income 30% of aerospace jobs 20% of manufacturing / wholesale trade jobs Critical Infrastructure

5 Three objectives: Reduce risks from flood and channel migration hazards Minimize the environmental impacts of flood projects Reduce long term maintenance costs

6 Flood Control District Operating Programs How do we reduce flood risks? 1. Identify hazards 2. Assess risk and vulnerabilities 3. Build awareness of hazards 4. Develop a plan and strategy to reduce risks 5. Actions to avoid risk 6. Actions to reduce or mitigate risk 7. Evaluate, learn, and adjust ILA Work Program Categories 1. Flood Preparedness, Regional Flood Warning Center, and Post Flood Recovery 2. Planning, Grants, Mitigation, and Public Outreach 3. Flood Hazard Assessments, Mapping, and Technical Studies 4. Resource Management, Annual Maintenance, and Facility Monitoring 5. Capital Investments: Construction and Repair, Acquisitions and Elevation

7 Tools to reduce but not eliminate risk: Source: FEMA and USACE

8 Eligibility requires regular inspections and compliance with Corps levee maintenance requirements Activity Who are our partners in reducing flood risk? Communicating Risk: Flood Warning and Preparedness Planning and Prioritizing Actions Partners USGS, NOAA, Corps, Seattle, Emergency Management, local governments Take Winter by Storm regional partnership Local governments through Basin Technical Committees and Advisory Committee Actions to Reduce Risk Project Design, Permitting, and Mitigation Funding to Support Regional Partners Maintenance and Repairs Corps, FEMA, Ecology, local governments, funding partners Fisheries co-managers (tribes and WDFW), Corps, Ecology, local agencies Provide $12.9 million in 2016 to jurisdictions, agencies, non-profits, and tribes to support complementary floodplain management efforts. Federal funding following disasters for levees (Corps PL 84-99) and revetments (FEMA public assistance)

9 Funding Partnership Examples Grant Source Corps PL Levee Repairs What is it for? Cost-share levee repairs following federally-declared disasters. Corps will fund repairs to levees (structures that contain floodwaters) but not revetments. Levee maintenance policies for vegetation on levees have been the subject of much debate over the last several years; the Corps SWIF process offers an alternative to resolve these debates. Program is generally more cost-effective in constrained urban areas like the Green than in less constrained areas with higher quality habitat like the Snoqualmie and Cedar. FEMA Public Assistance Revetment Repairs FEMA Hazard Mitigation Grants Floodplains by Design Cost-share revetment repairs following federally-declared disasters, plus flood response costs. FEMA will fund repairs to revetments (structures that prevent riverbank erosion but do not contain floods). Cost-share acquisition and elevation of at-risk homes. Majority of the available funding is intended to reduce insurance claims to the National Flood Insurance Program; in recent years funding tends to go toward homes that have insurance and multiple large damage claims in the Southeast United States. State capital funding through the Department of Ecology. Funding for large-scale multi-objective projects combining public safety, habitat

10 Overview of Accomplishments 79 projects to reduce flood risks 64 homes elevated, with 12 more underway 27 farm pads built for flood refuge, 3 agricultural structures elevated Barn Elevation, Lower Snoqualmie Valley 186 at-risk structures acquired on 450 acres to move people out of harms way 6,500 Flood Alert subscribers, 2,600 flood app downloads Flood Warning Center opened 43 times, 1,296 hours of operation Over $52 million for multi-objective projects from multiple grant sources

11 Accomplishment: Improved channel migration mapping Cedar River Channel Migration Maps (2015) Taylor Creek Confluence Next: South Fork Skykomish, Tolt, White

12 Accomplishment: Landslide Investigation (Major River Floodplains)

13 Accomplishment: Improving flood awareness Flood safety videos available in 22 languages Flood Update mailed to 18,000 floodplain addresses each year Flood information available in multiple languages

14 Accomplishment: Flood Warning and Patrols Warning Center activated 43 times for 1,296 hours Over 6,500 flood alert subscribers Smart phone application over 4,800 subscribers

15 Accomplishment: Cedar River Rainbow Bend

16 Accomplishment: Green River Reddington Levee

17 Upcoming Projects South Fork Snoqualmie, I-90 / North Bend ( ) White River, Countyline ( ) Lower Snoqualmie Tolt Pipeline (2017)

18 Upcoming Projects: Willowmoor 23

19 City Partnership Projects Seattle ( ) Lake Forest Park (2015) Bellevue ( ) Renton ( )

20 Corps Levee Repair Partnerships ( ) $10.8 million total project cost $4.5 million local share Desimone Reach 1 Floodwall, Tukwila Dykstra Levee, Auburn

21 Evaluation Criteria: Project Evaluation Approach Implementation Opportunity Potential Address Project RESCOPE Constraints or Rescope High Flood Risk Reduction Potential Medium Priority Priority NOT A PRIORITY Low Priority NOTE: This is a conceptual diagram and is not intended to imply clear and distinct thresholds between these categories.

22 Capital Project Planning River Corridor Plans Corridor Planning Phase Phase 1: Risk Characterization Phase 2: 6-year Capital Investment Plan based on existing placeholder funding Phase 3: Integrative multi-objective plans River System Cedar (2016) Tolt (2016) MF Snoqualmie (2017) SF Snoqualmie (2016) Cedar (2016) Lower Green River

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24 Snoqualmie and South Fork Skykomish Flood Risks Flood inundation Channel migration Bank erosion Alluvial fan hazards

25 South Fork Snoqualmie Corridor Plan Existing Conditions 100-yr Flow 500-yr Flow

26 South Fork Snoqualmie 6-Year Capital Investment Strategy FCD adopted framework with goals, objectives, approaches Characterization of conditions complete Stakeholder and public meetings last October Alternatives evaluation nearly complete FCD Possible Action Sept 2016 Setting up for a boring to evaluate levee stability

27 Tolt River 6-Year Capital Investment Strategy Lower Tolt River upstream of Carnation Levees unstable, do not contain floodwaters 60 homes in high risk areas Hwy 203 and Tolt River Road subject to inundation FCD adopted framework with goals, objectives, approaches Characterization of conditions nearly complete Stakeholder and public meetings January 2015

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29 Cedar River Strategy Reduce flood velocities and volumes that threaten critical public infrastructure, residential dwellings, and block sole-access roads Reduce public safety risks associated with neighborhood-scale flooding and channel migration

30 Cedar River Corridor Plan Complete risk characterization 6-year capital investment strategy in 2016

31 General Approach to Corridor Plans Multi-objective: Scope and goals based on Flood Plan and County policies Flood inundation, erosion, channel migration where applicable Ecological resources, including salmon habitat where present Economy, agriculture, recreation, other community goals Characterize existing and potential future conditions Develop and evaluate alternatives Long-term: What will it take to be done? Near-term: Priority actions for 6-10 year CIP Recommend long-term strategy and near-term actions Key is to customize to the needs of the river basin and segment!

32 Green River System-Wide Improvement Framework (SWIF) Interim SWIF submitted to Corps in Feb 2016 Maintain eligibility for Corps repair funding Lower Green River Corridor Plan and EIS Potential Exec Cmte action in June

33 Lower Russell Rd Levee Setback Lower Russell Road, Green River Reconstruct 1.4 mile levee to improve flood protection, restore habitat, and enhance recreational opportunities $43 Million total project cost $17.4 Million FCD $4.9 Million WA State Floodplains by Design grant funding

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35 Questions? Brian Murray, Environmental Programs Managing Supervisor (206)