C-SMART: Planning for Sea Level Rise in Tomales Bay, September 23, 2016 Jack Liebster, Planning Manager, Marin County

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3 C-SMART: Planning for Sea Level Rise in Tomales Bay, September 23, 2016 Jack Liebster, Planning Manager, Marin County

4 Sustainable Marin?

5 Sea Level Rise Adaptation Process Evaluate Science Info. Implement & Monitor Identif Assets Plan Action Assess Vulnerability Evaluate Adaptations

6 Uncertainty in Estimates Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 4

7 Identifying Future Risk with CoSMoS 1. Global forcing using the latest climate models 2. Drives global and regional wave models 3. Scaled down to local hazards projections

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9 EXPOSURE SLR VS. ANNUAL STORM

10 December 3, Mill Valley

11 December 3, Mill Valley

12 Today

13 1.6 feet SLR

14 3.3 feet SLR

15 3.3.feet SLR

16 Today

17 6.6 feet SLR

18 16.4 feet SLR

19 ASSET MAPPING & INVENTORYING I & M Plan Science Assets Vulnerabl. Mapping people; livelihoods; environmental services and resources; infrastructure; and economic, social, & cultural assets Evaluate Agricultural land Protected areas Public beaches and parks Dunes River & streams Wetland areas Habitat areas Oyster beds Sandspits Shorebirds Roads and transportation Trails Buildings Residential development Commercial buildings Schools Elderly/mobility limited facilities Hotels/Motels Harbors and marinas Fishing, aquaculture facilities Utilities & services Septic leach fields Water Supply wells Archeological/ Paleontological sites Historic sites

20 The Vulnerability Assessment Tool

21 Community Vulnerability

22 Local Citizens Providing Additional Information on Assets at Public Workshops

23 Game of Floods Board Workshops 21

24 Excerpt of Table of Contents

25 Key Findings 4,700 acres exposed at mean higher high water Mean higher high water: The average high tide, thus some sites could be dry during lower tides. Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 23

26 Key Findings 1,100 buildings 1,300 parcels 22% of residential, 33% of commercial Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 24

27 Key Findings 20 miles of roads including Shoreline Hwy, Calle del Arroyo, Olema-Bolinas Rd., and Sir Francis Drake Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 25

28 Key Findings $300 million in assessed value, market value is higher $7 million in property tax $700,000 in Transient Occupancy Tax Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 26

29 Key Findings Utilities, septic and drinking water systems Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 27

30 Marshes could convert to mud flats or move upland Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 28

31 Key Findings Beaches could flood and erode Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 29

32 Chicken Ranch Beach at King Tide Credit: Richard James for California King Tides Project Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 30

33 Inverness at King Tide Credit: Abe Doherty for California King Tides Project Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 31

34 Natural Assets Vulnerability Assessment Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 32

35 Community-Specific Adaptation Concepts Approach Protect (hard and soft) Accommodate Retreat Timeframe for implementation (based on timing of impacts feasibility, public support and cost are currently being assessed) Near-term Medium-term Long-term Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 33

36 Near-term Restore and enhance wetlands Oyster reef/ living shorelines Elevate/floodproof buildings Permit houseboats Replace old septic systems Medium-term Convert road segments to levee Construct horizontal levee Elevate or realign road segments Community wastewater system Remove/relocate development Long-term Convert additional road to levee Remove/relocate development Boat moorings Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 34

37 LCP Policies for coastal hazard areas 1. Perform a sea level rise hazards analysis as part of a Coastal Development Permit for new projects on vacant land or for projects that expand the size of existing development by 50% unless exempt or Categorically Excluded. 2. Allow waivers or seek a Categorical Exclusion for projects in coastal hazard areas, including structures in the 100-year floodplain, that meet certain standards. Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 35

38 Policies for coastal hazard areas 3. Raise building height limits in coastal hazard areas to allow for adaptation to sea level rise. 4. Encourage the creation of local self-funded assessment districts to manage common hazard risks. 5. Evaluate a managed retreat program. 6. Prioritize adaptation options that protect, enhance, and maximize protection of coastal resources and public access. Community Development Agency Collaboration: Sea-level Marin Adaptation Response Team December 10, Slide 36

39 We Could Go This Way

40 or This.

41 Collaboration with Stanford s Center for Ocean Studies on Natural Capital

42 Seagrass and Oyster to Calm the Waters?

43 Living Shoreline Oyster beds in SF Bay 41

44 Oyster Reef Complex

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46 Structural Protection 44

47 A Personal Invitation

48 Questions?

49 Draft V.A. available at Hard copies at West Marin libraries Mail comments to: Marin County Community Development Agency c/o Vulnerability Assessment 3501 Civic Center Drive, Suite 308 San Rafael, CA Or THANK YOU!

50 Community Development Agency 3501 Civic Center Drive, Suite 308 San Rafael, CA T / F marinslr.org

51 Game of Floods : Pt. Reyes Station