Coastal Hazards Vulnerability and Fiscal Impact Study Report:

Transcription

1 Agenda Item B.1 Coastal Hazards Vulnerability and Fiscal Impact Study Report: Vulnerability Assessment and Adaptation Strategies Review October 12, 2015 Planning Commission Meeting Presentation by: Anne Wells, Advance Planning Manager Dave Revell, Ph.D., Revell Coastal

2 Slide 2of 36 Coastal Hazards Vulnerability and Fiscal Impact Study Report Purpose of Report: Provide scientific, economic and technical analyses to support incorporating new State policy guidance on climate change into the Local Coastal Program. Identify vulnerable assets, adaptation measures and implementation strategies to guide the development of policy and regulations as the City faces future increases in sea level rise, storm, and flood frequency.

3 Slide 3of 36 Report Outline Overview Section 1: Introduction Section 2: Background and Existing Conditions Section 3: Vulnerability Assessment Section 4: Fiscal Impact Analysis Section 5: Adaptation Strategies Section 6: Recommendations Section 7: Summary and Conclusions

4 Slide 4of 36 Vulnerability Assessment Evaluates the impacts of each type of hazard (e.g. erosion, flooding, inundation) Assesses impacts to each asset category over time (e.g. infrastructure, habitat, utility) Identifies thresholds in either time or rise in sea level Flooding at Fairview and Hollister (1998)

5 Slide 5of 36 Climate Change Impacts Temperature Temperature Changes Summary by 2100 Temperature: 4.5 to 5.3 F 6.0 Temp (F) High 2060 High 2100 High 2100 Low Annual Temp. Change ( F) January Temp. Change ( F) August Temp. Change ( F)

6 Slide 6of 36 Climate Change Impacts Extreme Heat # of Days Between April Oct Changes in Extreme Heat (79 F) Summary by 2100 # of Extreme Heat Days: days Duration of Heat Waves: 7 20 days 10 0 Existing Conditions 2030 High 2060 High 2100 High 2100 Low Duration of Heat Wave (# days/year) Extreme Heat Days (# days/year)

7 Slide 7of 36 Climate Change Impacts Sea Level Rise Planning Horizons 2010, 2030, 2060, 2100 Sea Level Rise High: 60.2 inches by 2100 Medium: 30.7 inches by 2100 Low: 10.6 inches by 2100 Sea Level Rise in cm Santa Barbara South Coast No land motion

8 Slide 8of 36 Model Inputs Physical Forces Sea Level Rise scenarios Transformed nearshore waves Tides Total Water Levels Backshore Characterization Geology Geomorphology (slopes, heights) Backshore type (cliff, dune, inlet, armored) Historic erosion rates (short term, long term) Topography Revell et al 2011, PWA 2009 Scale of Analysis 500m

9 Slide 9 of 36 Model Outputs 1. Erosion Hazards Future erosion increases hydraulic connection and risk of flooding 2. Coastal Flooding Inundation during extreme coastal events (integrated with erosion) 3. Wave Velocity Zone of wave momentum (similar to FEMA V Zone) 4. Rising Tides Inundation during monthly extreme tides [not shown] 5. Relative Risk Attempt to represent the ranges of uncertainty ESA 2015

10 Slide 10 of 36 Categories of Vulnerable Assets Parcels and buildings Land use Emergency services Habitats 2100 Infrastructure Water supply Wastewater system Utilities Roads Oil and gas Hazardous materials Public transportation Recreation and access

11 Slide 11 of 36 Vulnerability Assessment Recreation: Trails and Access as of 2010 Length of trails by hazard type (feet) Erosion = 0 Coastal Flooding = 2,444 Total = 2,444

12 Vulnerability Assessment Recreation: Trails and Access in 2030 Slide 12 of 36 Length of trails by hazard type (feet) Erosion = 3,684 Coastal Flooding= 4,115 Total = 7,799

13 Vulnerability Assessment Recreation: Trails and Access in 2060 Slide 13 of 36 Length of trails by hazard type (feet) Erosion = 6,914 Coastal Flooding= 7,792 Total = 14,706

14 Vulnerability Assessment Recreation: Trails and Access in 2100 Length of trails by hazard type (feet) Erosion = 11,443 Coastal Flooding= 13,634 Total = 25,077 Slide 14 of 36 Measures of Impact Percent of trail by hazard type Number of disruptions or breaks in trail network by hazard type Realignment cost Recreational value

15 Vulnerability Assessment Land Use and Buildings in 2010 Slide 15 of 36

16 Vulnerability Assessment Land Use and Buildings in 2100 Slide 16 of 36 Number of parcels by hazard type (acres) Erosion = 6 (3.5) Commercial = 2 (30.9) Ag/Open Space = 4 (89) Coastal Flooding = 282 Residential = 91 (4.4) Industrial = 85 (54.6) Commercial = 71 (96.8) Infrastructure = 10 (9.5) Ag/Open Space = 25(106.7) FEMA Creek Flooding Residential = 500 (64.7) Industrial = 143 (101.7) Commercial = 187 (154.5) Infrastructure = 34 (40.1) Ag/Open Space = 61 (103.9)

17 Vulnerability Assessment Land Use and Buildings in 2100 Slide 17 of 36 Residential Industrial Commercial Infrastructure Ag/Open Space Erosion Coastal Flooding River Flooding Measures of Impact #of parcels by hazard type Acreages Value (dollars) # of buildings by hazard type Depth of flooding at buildings Developed vs. undeveloped land

18 Vulnerability Assessment Schools Slide 18 of 36 One school in existing FEMA flood map Goleta Union School District Headquarters NO coastal confluence modeling to project future creek flooding Waldorf and Montessori School and others in immediate vicinity Data Gap Coastal Confluence Modeling

19 Slide 19 of 36 Environmentally Sensitive Habitat Areas Environmentally Sensitive Habitat Area Existing Conditions Coastal Erosion Beach and Shoreline Monarch butterfly and/or Raptor Roosting Habitat Native grassland Riparian/Marsh/Vernal Scrub Beach and Shoreline Coastal Flooding Monarch butterfly and/or Raptor Roosting Habitat Native grassland Open Water Riparian/Marsh/Vernal Scrub Unvegetated Open Creek Channel Measures of Impact Acreages Not habitat evolution (data gap)

20 Length of Pipe (ft) (manholes) Vulnerability Assessment Wastewater in 2100 Slide 20 of 36 Coastal Flooding Pipe = 22,945 feet (4.3 miles) Manholes = 82 1 Pump Station Measures of Impact Replacement Cost Retrofit costs

21 Slide 21 of 36 Vulnerability Assessment Hazardous Materials and Storage 2100 Hazardous Material Storage & Underground Storage tanks Coastal Flooding Existing = = = = 84 Creek Flooding (existing only) = 258 sites Measures of Impact # of sites by type Cost of clean up

22 Slide 22 of 36 Vulnerability Assessment Roads 2010 Length of roads (ft) Coastal Flooding * = 1159 feet Creek Flooding FEMA * = 71,626 feet = 13.6 miles * Not including Hollister

23 Slide 23 of 36 Vulnerability Assessment Roads 2100 Length of roads (ft) Coastal Flooding = 19,008* = 9.28 miles * Not including Hollister Measures of Impact length of roads (including Hollister) # of interruptions lost traffic trips depth on road

24 Slide 24 of 36 Vulnerability Assessment Oil and Gas 2100 Coastal Flooding = 52 Coastal Erosion = 53 River Flooding (existing only) = 2 Measures of Impact # of sites by type Miles of pipeline and location are data gaps

25 Vulnerability Assessment Emergency Services 2100 Slide 25 of 36 Includes Fire, Police, and Medical (only in City) Coastal Flooding = 0 Fire = 0 Police = 0 Medical Coastal Erosion = 0 Creek Flooding (existing only)= 2 Fire = 0 Police = 2 Medical = 0 Measures of Impact # of facilities by type (police, fire, medical) Proximity to City?

26 Vulnerability Assessment Water Supply Slide 26 of 36 NO MAP allowed under data sharing Measures of Impact Length of pipe # of pump stations # of hydrants # of wells # of valves Length of reclaimed water (potential data gap)

27 Vulnerability Assessment Utility SCE Slide 27 of 36 NO MAP allowed under data sharing NO MAP Measures of Impact Length above ground Length below

28 Slide 28 of 36 Economic and Fiscal Impact Analysis Purpose: Estimate losses due to sea level rise/coastal storms/ coastal erosion Analysis will include: Infrastructure (roads, water, etc.) Land Buildings Loss in economic activity and tax revenues Increased public safety costs Increased clean up costs

29 Sea Level Relative to MSL in 2000, in Recurrence Intervals of Extreme Water Levels Yr. 10 Yr. 1 Yr. 2 MTh 1 MTh Cost / year $500 $2,500 $25,000 $150,000 $300,

30 Slide 30 of 36 Preliminary Vulnerability Findings City most vulnerable to coastal flooding impacts (potentially fluvial/coastal confluence) Coastal erosion has minimal impact to the City except for: Recreation and Trails Bacara by 2060 Sandpiper by 2030 Substantial escalation of impacts between 2060 and 2100

31 Slide 31 of 36 What are Adaptation Strategies? Avoid hazards Move development away from hazards Move hazards away from development Provide barriers between hazards and development Flood proof More Disasters Higher Costs Risk Community Acceptance of Risk Time or Sea Level Elevation

32 Slide 32 of 36 The City can t adapt to climate change alone the County, Airport, and UCSB are our partners. February 28, 2014

33 Slide 33 of 36 Types of Adaptation Strategies (1 of 3) Do nothing Managed realignment of infrastructure over time Elevating to reduce impacts Armoring and protecting resources in place Inlet management engagement Sediment management Policy options

34 Slide 34 of 36 Types of Adaptation Strategies (2 of 3) Sediment management Beach nourishment Opportunistic beach nourishment Utilizing cobbles to protect resources Changing debris basin management Storm berms to protect resources

35 Slide 35 of 36 Types of Adaptation Strategies (3 of 3) Transfer of Development Rights in high risk areas Utilizing zoning regulations to support strategies Hazard overlays Site specific report triggers Real estate disclosures for hazards Regular public education Monitoring effectiveness of strategies Financing for public acquisition of high risk areas

36 Questions? Slide 36 of 36