Presentation Outline. Project Overview. Sea Level Rise Assessment & Decision Tools. Community Engagement. Tina Whitman, Friends of the San Juans

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1 Healthy Beaches for People & Fish Sea Level Rise Adaptation Tools for San Juan County, WA Tina Whitman & Andrea MacLennan December 10, 2015 Presentation Outline Project Overview Tina Whitman, Friends of the San Juans Sea Level Rise Assessment & Decision Tools Andrea MacLennan, Coastal Geologic Services Community Engagement Tina Whitman, Friends of the San Juans

2 Healthy Beaches for People & Fish Sea Level Rise Adaptation Tools for San Juan County, WA Tina Whitman and Andrea MacLennan Project Overview Partners: Friends of the San Juans Coastal Geologic Services Salish Sea Biological Resource Media Funders: U.S. EPA North Pacific LCC Sustainable Path Foundation Bullitt Foundation Technical Team: Washington Departments of Ecology, Natural Resources and Fish and Wildlife, The University of Washington, Tulalip Tribes, Samish Indian Nation, United States Geological Survey, Padilla Bay National Estuarine Research Reserve San Juan County Public Works, SJC Salmon Recovery, Puget Sound Partnership

3 Healthy Beaches for People & Fish Sea Level Rise Adaptation Tools for San Juan County, WA Project Overview > 400 Miles Marine Shoreline Diverse Shoreform Types High Ecosystem Services Non-urban Flood & Erosion Hazards Vancouver, BC Good place to develop & test sea level rise adaptation tools Seattle, WA

4 Healthy Beaches for People & Fish Sea Level Rise Adaptation Tools for San Juan County, WA Project Overview New Research SLR Vulnerability Model SLR Regulatory Review Tidal Elevation of Surf Smelt Spawn Manager Outreach Local and Regional Interviews, Surveys, Focus Groups & Workshops Mgt. Recommendations Community Engagement Decision Tools, King Tide Events, Workshops & Surveys Adaptation Projects Public Infrastructure/Habitat Relocation of Private Homes Improved Policy

5 Sea Level Rise Decision Tools Sea Level Rise Vulnerability Assessment of San Juan County December 10, 2015 By: Andrea MacLennan, MS Coastal Geologic Services

6 Make Informed Decisions How will my shoreline respond to sea level rise? How vulnerable is my property? What are appropriate responses for my type of shoreline? Shoreform Response San Juan County Vulnerability Assessment Appropriate Adaptation Approaches

7 Make Informed Decisions Shoreform San Juan County Response Vulnerability Assessment Appropriate Adaptation Approaches Different shoreforms will respond differently What type of hazards? (erosion or floods? both?) When? 2050/2100? What are longterm vs short term solutions? Costs?

8 Shoreform Response Different shoreforms will respond differently Shoretype Topography Geology Sediment supply Littoral drift cells No Appreciable Drift Space to move landward Septic?

9 Shoreform Response Different shoreforms will respond differently Increase in water levels, high tides Increase bluff/bank erosion Natural shorelines will move landward More frequent high water events storms and el ninos Habitat loss via coastal squeeze armored shores

10 Shoreform Response Rocky Shores Vertical shift upwards/landward shift in tidal elevation Similar shift in intertidal habitats

11 Shoreform Response - Bluffs Landward shift of entire beach profile Bluff erosion enables local and down-drift beaches to adjust

12 Shoreform Response Barrier Beaches Crest of berm will build higher and shift landward via overwash Landward shift in habitats, dune grass, driftwood, intertidal spawners Habitat/beach loss can occur where landward constrains limits natural migration of beach features

13 Shoreform Response - Artificial Static shoreline armor prevents landward migration of shoreline and habitats resulting in habitat and beach loss

14 Make Informed Decisions Shoreform San Juan County Response Vulnerability Assessment Appropriate Adaptation Approaches Different shoreforms will respond differently What type of hazards? (erosion or floods?) When? 2050/2100? What are longterm vs short term solutions? Costs?

15 San Juan County Vulnerability Assessment Objectives Develop a GIS tool to visualize SLR implications that integrates bluff erosion and inundation Identify structures and roads vulnerable to erosion and inundation Identify priority areas and potential management strategies

16 San Juan County Vulnerability Assessment SLR Projections National Research Council 2012 Sea Level Rise for the Coasts of California, Oregon and Washington: Past, Present, and Future ISBN The project Technical Advisory Group recommended using 2 scenarios and 2 planning horizons NRC SLR Projections (NAS 2012) 2050 (ft) 2100 (ft) Moderate (IPCC A1B) Scenario High (IPCC A1FI) Scenario

17 San Juan County Vulnerability Assessment Create the Inundation (Bath Tub) Model Step 1. Created a countywide MHHW shoreline MHHW = Mean Higher-High Water Step 2. Linked that with topography Step 3. Created contours for Highest Observed Water Level (HOWL) and each scenario and time horizons (2050 Mod, 2050 High, 2100 Mod, 2100 High) Step 4. Create polygons from lines

18 San Juan County Vulnerability Assessment Erosion Rates Background erosion rates from a stratified sample of shoretypes (1-2%). - Feeder bluffs, - Transport zones - Pocket Beaches - Accretion shoreforms Exposure, Orientation DSAS, 1960s

19 San Juan County Vulnerability Assessment Buffering Bluff Erosion Bluff crest was digitized from LIDAR slope data Estimated future erosion was buffered from bluff crest Shoreform ( ft) Scenario (Mod, High) Planning horizon (2050, 2100) Structures and roads were selected that intersect Profile view of future erosion estimates NOT to SCALE

20 San Juan County Vulnerability Assessment Uncertainty, Assumptions and Limitations NOT a predictive tool, developed to enhance understanding and facilitate planning Detailed error analysis in report Error analysis included measures of cumulative error Cumulative error was mapped as polygons to bracket results Not all drivers of change accounted for in the model Uncertainty in rate of accelerated bluff retreat and sea level rise

21 San Juan County Vulnerability Assessment Assess vulnerability to floods and erosion

22 SJC Vulnerability Assessment Threatened Roads: Flood Assess road access vulnerability to flooding

23 SJC Vulnerability Assessment Threatened Roads: Eros Assess road access vulnerability to erosion

24 Make Informed Decisions Shoreform San Juan County Response Vulnerability Assessment Appropriate Adaptation Approaches Different shoreforms will respond differently What type of hazards? (erosion or floods? When? 2050/2100? What are longterm vs short term solutions? Costs?

25 Appropriate Adaptation Approaches Appropriate Adaptation Approach Planning horizon Cost of infrastructure Maintenance Opportunities Habitat conservation / restoration Increased resilience

26 Appropriate Adaptation Approaches - Relocate Effective for managing erosion and inundation in the long-term Requires adequate upland area for relocation Often cheaper than engineered solutions Most effective for septic, outbuildings, and highly vulnerable primary structures

27 Appropriate Adaptation Approaches - Elevate Only effective for managing coastal flooding, not erosion Driftwood can damage pilings, elevated structures

28 Appropriate Adaptation Approaches - Fortify Shore armor has limitations: Only effective for managing erosion, not flooding Will not curb all bluff erosion

29 Appropriate Adaptation Approaches - Nourish Nourish entire beach profile Build a storm berm, to absorb wave energy Compensate (short-term) for lost sediment supply or habitat loss

30 Appropriate Adaptation Approaches Bluffs Barrier beaches Pocket beaches Relocate structures Nourish entire beach profile Nourish storm berm Nourish waterward of armor Elevate Fortify The most appropriate approach depends on site-specific conditions

31 Want to learn more? DOT com

32 Partners: FRIENDS of the San Juans Coastal Geologic Services Resource Media Funders: U.S. EPA North Pacific LCC Sustainable Path Foundation FRIENDS Membership Sea Level Rise Adaptation Tools San Juan County, WA Engaging Managers & Community Members Tina Whitman, MS FRIENDS of the San Juans dot org

33 SJC Sea Level Rise Adaptation Tools Multiple Scales of Sea Level Rise Outreach Efforts 1. Regional Managers Regulators, Managers, Scientists 2. County Managers County Public Works and Planning Departments, Conservation Entities 3. Community Focus Area Workshop and Survey of Residents and Property Owners 4. Lessons Learned and Next Steps

34 Manager Outreach SJC Sea Level Rise Adaptation Tools Stakeholder Interviews 39 federal, state, tribal and county scientists, regulators, managers Focus Groups 17 federal, county, state, tribal and ngo managers Surveys 20 federal, state, county and city planners Technical Team County, state agency, federal, tribal scientists and managers County Workshops Public Works, Planning, Conservation Groups

35 SJC Sea Level Rise Adaptation Tools In the future, normal tides may look more like today s extreme tides Local Outreach- vulnerable communities King Tide Events 2015 Low Tide 2012 King Tide Ginny Sherrow Photo

36 SJC Sea Level Rise Adaptation Tools Local Outreach- vulnerable communities Shaw Island Community Workshop 39 residents 2/3 shoreline property owners Workshop Partners & Roles Regional SLR WA Sea Grant Local shorelines 101- FSJ SLR vulnerability assessment- CGS Local adaptation projects- FSJ Live-results, anonymous participant polling- WA Sea Grant

37 SJC Sea Level Rise Adaptation Tools Local Outreach- vulnerable communities Shaw Island Community Survey Results

38 SJC Sea Level Rise Adaptation Tools Local Outreach- vulnerable communities Shaw Island Community Survey Results

39 SJC Sea Level Rise Adaptation Tools SJC Sea Level Rise Adaptation Tools Local Outreach- vulnerable communities Shaw Island Community Survey Results

40 SJC Sea Level Rise Adaptation Tools SJC Sea Level Rise Adaptation Tools Local Outreach- vulnerable communities Shaw Island Community Survey Results

41 SJC Sea Level Rise Adaptation Tools Local Outreach- vulnerable communities Shaw Island Community Survey Results

42 SJC Sea Level Rise Rise Adaptation Tools Tools Local Outreach- vulnerable communities Shaw Island Community Survey Results Example image testing- Shaw community event survey

43 SJC Sea Level Rise Rise Adaptation Tools Tools Local Outreach- vulnerable communities Shaw Island Community Survey Results Example image testing- Shaw community event survey

44 SJC Sea Level Rise Adaptation Tools Lessons Learned Management Structure Improved or different frameworks are needed to support the implementation of adaptation and multi-benefit projects; Real Life Examples Successful on-the-ground adaptation case studies from our region will be key; Expanded Community Engagement Public feedback to managers is essential.

45 SJC Sea Level Rise Adaptation Tools Next Steps Additional community workshops and surveys. Cost/benefit analysis for adaptation case studies. Implement multi-benefit adaptation projects. Annual King Tides events with Conservation collaborators.

46 Sea Level Rise Adaptation Tools San Juan County, WA Project Reports at: dot org dot com