Vulnerability and Adaptation to Sea Level Rise

Transcription

1 Hermosa Beach Community Meeting April 14, 2014 Vulnerability and Adaptation to Sea Level Rise Addressing Coastal Risks through Hermosa Beach s General Plan Susanne Moser, Ph.D. Julie Ekstrom, Ph.D. Susanne Moser Research & Consulting

2 Overview 1. RISKS How much sea level rise and associated flood and erosion risks does the City face? 2. VULNERABILITIES Where and in what ways are infrastructure, the built environment, business activity and city residents vulnerable? 3. PREPARATION AND RESPONSE OPTIONS How can the City address these risks and reduce its vulnerabilities through appropriate preparatory and adaptive actions?

3 Part I Photo: oracletalk.com Sea Level Rise and Risks to Hermosa Beach

4 Source: Walsh et al. (2014, draft)

5 Source: Walsh et al. (2014, draft)

6 Source: Walsh et al. (2014, draft)

7 Source: Walsh et al. (2014, draft)

8 Influences on Global and Regional SLR Source: NRC (2012)

9 What about the S. California Coast? Historical SLR: 8 inches Avg. California SLR by 2030: 6 in ( in. range) 2050: 12 in (5-24 in. range) 2100: 36 in (16-66 in. range) More in southern California than Northern California Source: NRC (2012)

10 Storms, El Niños Will Magnify SLR Source: Caldwell et al (2013)

11 Source: NRC (2012) Global sea level is rising primarily because land ice is melting and ocean water is expanding as it warms ~ 8 in. over 20 th century (from tide gages) Since 1993 ~double that rate (from satellites & tide gages) Over 21 st century: 4-7 x historical rate

12 What Effects Can We Expect in Hermosa Beach and Along LA County? Waves and run up reach higher elevations and extend farther inland Increased erosion of beaches Increased risk of bluff failures Coastal flooding with higher surges, flood elevations Permanent inundation of natural habitat Reduced capacity to absorb runoff Saltwater intrusion into coastal groundwater storm All of this worse if tracking on the high end scenario Photo: huffingtonpost.com

13 Source: Ekstrom & Moser (2014) Hermosa Beach 100 year flood zone with 55 inches of sea level rise (red)

14 Historical Threat of Coastal Erosion Source: based on Thieler and Hammer Klose (2000)

15 Hermosa Beach View toward King Harbor, Redondo Beach Source: Image Science and Analysis Laboratory, NASA Johnson Space Center

16 Part II Photo: csc.noaa.gov Social, Economic and Infrastructure Vulnerabilities

17 Photos from Wikimedia Commons

18 Guidance on Key Terms Climate Change Impacts Consequences of climate change on natural and human systems (the hazards potentially faced or actually experienced). Vulnerability = Susceptibility to change or harm from climate variability, climate change and climatic extremes. Exposure = The degree to which a system is at risk, i.e., would experience the threat, if it unfolded. Sensitivity = The degree to which a system is affected, either adversely or beneficially, by climatic hazard (i.e., the potential severity of impact if experienced). Adaptive capacity = The ability of a system to respond to climate change (including climate variability and extremes), to moderate potential damages, to take advantage of opportunities, and to cope with the consequences. Adaptation = Adjustments in natural or human systems in response to actual or expected climatic hazards, aimed at minimizing harm or taking advantage of beneficial opportunities.

19 Social Vulnerability Not everyone is equally vulnerable! Range of factors matter: Income and poverty Race Females as head of household Age Housing type (percent rentals) Physical and mental illnesses and disabilities Transient populations Photos (t>b): newsone.com; freeimages.com; S. Moser

20 Social Vulnerability Locally Integrated Perspective Source: Ekstrom & Moser (2014)

21 So. Vuln. and 100 year Flooding w/ 55 in. SLR Source: Ekstrom & Moser (2014)

22 Water Related Infrastructure >90% impermeable surface Back up of runoff during heavy rainfall events More street flooding Recent stormwater system overhaul very helpful Sewage system deficient, need for rehab already recognized Additional challenges from saltwater intrusion, corrosion

23 Structural Vulnerabilities 202 buildings exposed, incl. 143 residential buildings a church parking lot (at 1540 Hermosa Avenue) 13 government owned buildings Replacement value of buildings and contents (Hazus database) $35 million (in 2000$) Not incl. growth, infill, value change

24 Buildings at Risk Source: Ekstrom & Moser (2014)

25 Transportation Routes Emergency Response Source: Los Angeles County Draft General Plan (December 26, 2013) No major emergency routes impacts IN Hermosa Beach BUT: Access to those roads partially disrupted AND: Access to flooded neighborhoods limited

26 Tsunami Inundation/Evacuation Key Ares at risk now: Downtown District, Hermosa Avenue Hermosa Valley Elementary School 1645 Valley City Lifeguard 1201 The Strand Seven Pump Stations 3500 The Strand Sources: City of Hermosa Beach (tsunami inundation), Pacific Institute (flood w/ SLR)

27 Part III Preparation and Adaptation Options for Hermosa Beach

28 California coastline various adaptation needs and strategies No one size fits all But valuable lessons from other communities! Photos (l>r; t>b): USFWS; Wikimedia Commons; Coastal Records Project; USGS, Wikimedia Commons, Coastal Records Project)

29 Snapshot of California s Coastal Communities 45% 40% Where are California Coastal Communities in the Adaptation Process? (Status: Fall 2011) 40% 41% 35% 30% 25% 20% 15% 10% 5% 10% 9% 0% Not yet begun Understanding Planning Implementing Source: Finzi Hart, Griffman, Moser et al. (2013)

30 What Got Them Started? 50% Motivation to Begin Adaptation Planning 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% Source: Finzi Hart, Griffman, Moser et al (2013)

31 Adaptation Options: Sets of Examples Structural/Technical Hard and soft coastal protection (seawalls, beach replenishment) Artificial reefs Moving infrastructure inland/higher Stormwater system improvements Ecosystem restoration Planning & Policy Tools Setback regulations Building codes Land use policies Water rights Financial Mechanisms Insurance pools (risk sharing & transfer) Restoration/redevelopment funds Water trading schemes Ecosystem service payments Taxation Informational & Behavioral Approaches Education Disaster preparedness Decision support/climate services Improved warning systems Stakeholder engagement

32 Context Draft Guidance on Incorporating Sea Level Rise into Local Coastal Program (Updates) Released October 2013 Extended public comment period ended in mid February Currently finalizing

33 Coastal Commission Guidance Overarching Guiding Principles: A. Use Science to Guide Decisions B. Minimize Coastal Hazards through Planning and Development Standards C. Maximize Protection of Public Access; Recreation; and Sensitive Coastal Resources D. Maximize Agency Coordination and Public Participation Source: CA Coastal Commission (2013, draft)

34 Issue Areas to be Addressed in the LCP Update Issue Area Relevance 1 Public Access Yes 2 Recreation & Visitor-Serving Facilities Yes 3 Water Quality Protection Yes 4 Environmentally Sensitive Habitats and Other Natural Resources Yes 5 Agricultural Resources No 6 Planning and Locating New Development and Archaeological/Cultural Resources Yes 7 Scenic and Visual Resources Yes 8 Coastal Hazards Yes 9 Shoreline Erosion & Protective Devices Yes 10 Energy and Industrial Development No (yes) 11 Timberlands No Source: based on CA Coastal Commission (2013, draft)

35 Source: Ekstrom & Moser (2014) Adaptation Options Overview Ongoing Overarching Regional Strategies PURPOSE: Participate in regional alliances to improve scientific basis, develop regional approaches to maintaining beaches and to financing adaptation Ongoing Overarching Local Strategies PURPOSE: Build local government and community capacity to prepare for disasters and to adapt Specific Improvements in Disaster Preparedness and Recovery Planning PURPOSE: Improve near term disaster preparedness and increase local resilience

36 Adaptation Options A. Ongoing Overarching Regional Strategies Strategy 1: Continue Participating in the Regional Partnership in Climate Change Assessment and Adaptation Planning Substrategy 1.1 Participate in LARC. Substrategy 1.2 Update Scientific Basis for Coastal Adaptation Planning. Strategy 2: Pursue a Regional Approach to Sediment Management and Adaptive Shoreline Protection Substrategy 2.1. Participate in Regional Sediment Management Planning Substrategy 2.2. Develop a Long term Adaptive Shoreline Management Policy Substrategy 2.3 Conduct a Cost Effectiveness Assessment of Shoreline Adaptation Alternatives Substrategy 2.4. Develop Creative Local and Regional Financing Mechanisms for the Preferred Shoreline Adaptation Strategy. Source: Ekstrom & Moser (2014)

37 Adaptation options (cont.) B. Ongoing Overarching Local Strategies Strategy 3: Educate the Public about Flooding Risks and Promote Household Disaster Preparedness Substrategy 3.1. Develop Flood Risk Educational Materials and Distribute them Widely and Repeatedly. Substrategy 3.2. Survey Household level Preparedness and Develop Programs to Fill Disaster Preparedness Gaps Substrategy 3.3. Require Flood Risk Disclosure and Active Acknowledgment of Flood Risk in Property Purchases/Turn overs. Strategy 4: Educate the Public about Climate Change Risks and Adaptation Alternatives Substrategy 4.1. Communicate climate change risks and what the City is doing to address them. Substrategy 4.2. Provide frequent updates to the population to keep climate change messaging fresh, and to signal the importance of the issue Source: Ekstrom & Moser (2014)

38 Source: Ekstrom & Moser (2014) Adaptation Options (cont.) Strategy 5: Meaningfully Engage the Public in Adaptation Planning Direct communication and dialogue Clearly visible impact on range of adaptation options, and selection Strategy 6: Update Development and Redevelopment Policies Substrategy 6.1 Update Definitions Substrategy 6.2. Update Elevation Requirements of Infill and Redevelopment Substrategy 6.3. Update Building Height Restrictions to Account for Elevation Requirements on New/Redevelopment Above Base Flood Level Substrategy 6.4. Update Parking Requirements Associated with Infill and Redevelopment

39 Source: Ekstrom & Moser (2014) Adaptation Options (cont.) Strategy 7. Reduce Flood Vulnerability of Existing Structures Substrategy 7.1. Issue Guidance to Homeowners and Renters on How They Can Protect Floodprone Ground Floor Installations Substrategy 7.2. Floodproof Public Buildings. Substrategy 7.3. Develop Incentive Programs for Businesses to Floodproof their Establishments Strategy 8. Reduce Flood Vulnerability of Existing Infrastructure Substrategy 8.1. Continue Stormwater Runoff Improvements Substrategy 8.2. Increase Surface infiltration Throughout the City Substrategy 8.3 Integrate Sea Level Rise into the Repair and Replacement of Aging Infrastructure

40 Source: Ekstrom & Moser (2014) Adaptation Options (cont.) Strategy 9: Routinely Assess Synergies and Trade offs Between Climate Mitigation and Adaptation Policies, and between Climate and Non Climate Policies Substrategy 9.1. Require City Staff to Routinely Assess Implications of Local Government Action for Greenhouse Gas Emissions and Climate Change Risks Substrategy 9.2. Minimize Future Carbon Burden and Future Vulnerability to Climate Change Impacts Whenever Possible

41 Source: Ekstrom & Moser (2014) Adaptation options (cont.) C. Specific Improvements in Disaster Preparedness and Recovery Planning Strategy 10. Update Tsunami Emergency Response Planning Substrategy Require Future Tsunami Inundation Mapping to Include the Best Available Science on Sea Level Rise Substrategy Ensure that Tsunami Emergency Response Considers Social Vulnerability Before, During and After the Event Strategy 11. Improve Emergency Response Planning Substrategy 11.1 Review and Improve Evacuation, Emergency Response and Recovery Plans by Considering Identified Vulnerabilities Substrategy Assess the Costs and Benefits of Joining the National Flood Insurance Program

42 Selected Additional Resources Presentation based on draft report prepared by Ekstrom and Moser (2014), available from S. Moser. California Climate Change Portal California Adaptation Plan (2009, 2014 draft), Resources California Coastal Commission SLR Guidance (2014 draft) California Mitigation Policies and Activities California Climate Change and Energy related publications

43 Thank you! Susi Moser, Ph.D. Web: Julie Ekstrom, Ph.D. Web: