New Hampshire’s Coastal Risks and Hazards Commission Overview and Update Gulf of Maine Council Working Group Meeting October 15-16, 2014 Cliff Sinnott, Commission Chair Executive Director, Rockingham Planning Commission Exeter, NH

Commission Established SB-163 Introduced by Sens. Watters, Stiles, Clark in Jan An Act… “establishing a commission to recommend legislation to prepare for projected sea level rise and other coastal and coastal watershed hazards” Adopted and signed July 2, 2013 Commission first assembled August 16, 2013 Will sunset December 1, 2016

Commission Membership (= 37) 2 Senators, 2 House members Reps from 17 coastal & tidal municipalities State Agency designees from: Other Stakeholders: NHDESNH Office of Energy & Planning NH Fish & GameDRED – Commissioner’s office NHDOTDiv. of Parks and Recreation (DRED) Bureau of Public WorksDiv. of Historic Resources (DCR) NH HomebuildersPRIMEX Seacoast Board of RealtorsNHMA UNH - SeaGrantStrafford RPC UNH – Pres. designeeRockingham RPC

CRHC Mission “The purpose of the Coastal Risk and Hazards Commission is to develop sound guidance and recommendations for the state and municipalities regarding prudent and necessary changes to laws, regulations, plans, standards, and other actions that should be taken to prepare for anticipated sea level rise and increased future risks from coastal flooding, stormwater and related hazards.”

Approach End Product: Reports with guidance and recommendations to: legislature, state agencies, muncipalities Process: 1.gather facts; understand the science, quantify risks 2.receive input from stakeholders and the public 3.assess and evaluate 4.develop recommendations 5.report to the legislature, stakeholders, public Organization: Steering Comm., Science Adv. Panel, Sector Workgroups

Information needs Anticipated Future Conditions (ranges) – Sea level rise, 2050 & 2100 (CSRC/AECOM/RPC) – Areas vulnerable to coastal flooding, with SLR, storm surge (RPC Vulnerability Study) – Changes in precipitation (Wake report) – Impacts to wetlands and fisheries (NHF&G SLAMM model) – LiDAR based high resolution topography

Science Advisory Panel Established to help Commission interpret & assess peer-reviewed science Chaired by UNH CRHC member Dr. Paul Kirshen Focused on preparing guidance on future sea-level rise, storm surge, and precipitation based on existing published science Initial findings made July 2014 Panel suggests report update at least every 2 years

Figure 2.4. Global mean sea-level (GMSL) rise from 1860 to 2010 from Church and White (2011). GLOBAL MEAN SEA-LEVEL (GMSL) RISE Mean: 1.7 mm/yr (+/- 0.2) Mean: 3.2 mm/yr (+/- 0.4)

New England Sea-level Rise Figure 2.5 Portland 1.82 mm/yr (+/- 0.17) Seavey Island 1.76 mm/yr (+/-0.30) Boston 2.63 mm/yr (+/- 0.18)

Contributions to GMSL Rise 1993 – 2012 Table %

GMSL Rise Scenarios from US National Climate Assessment (Figure 2.7) Highest 6.6 ft Intermediate-High 3.9 ft Intermediate-Low 1.6 ft Lowest 0.7 ft

Planning guidance for risk averse assets

Storm Surge Sea-level rise increases the baseline water level for storm surges generated by extratropical and tropical storms. Estimates of future changes in storm surge remain uncertain. Wind

Observed Change: Trends in frequency and intensity are uncertain. Likely poleward shift in storm tracks. Projected Change: Future changes in frequency and intensity uncertain. Possible poleward shift in storm track. Storm Surge Extratropical storms develop north of the tropics. Strong easterly winds within the upper tier of the storm generate storm surge within Gulf of Maine.

Storm Surge Tropical storms form over tropical oceans and move poleward. Called hurricanes in the Atlantic if wind speeds exceed 73MPH. Observed Change: Increase in frequency, intensity and duration. Likely poleward shift in storm tracks. Change in response to: sea-surface temperature, tropical climate, and atmospheric circulation. Projected Change: Change in frequency uncertain. Likely increase in intensity and rainfall. Possible increase in frequency of major hurricanes. Possible shift in storm track toward northwestern Atlantic basin. Image Source: Unisys Image Source: Murakami and Wang (2010)

Precipitation Inland areas threatened by flooding from extreme precipitation. (Detailed assessment of precipitation trends and projections for NH in Wake et al. 2014) Image Source: NCA (2014) – Chapter 2 Total Precipitation – Northeastern US Observed Change: Increase in mean annual precipitation. Projected Change: Likely increase. Extreme Precipitation – Northeastern US Observed Change: Increase in the amount of precipitation falling during extreme events (largest 1% of total daily precipitation). Projected Change: Likely increase in number of extreme precipitation events.

Science Advisory Panel Findings & Guidance SEA-LEVEL RISE For coastal assets or areas with low risk tolerance: plan for “intermediate high” to “highest” scenario projections: – By 2050: 1.3 feet to 2 feet – By 2100: 3.9 feet to 6.6 feet EXAMPLES OF ASSETS WITH LOW RISK TOLERANCE: Essential Infrastructure (esp.: high cost and/or long design life) Densely settled areas Critical habitats Historical, archeological and valued cultural assets

Science Advisory Panel Findings & Guidance SEA-LEVEL RISE: Additional planning guidance:  Consider time period relevant to system/structure  Commit to manage to “intermediate high” range, be prepared to adapt to “highest” range  Update & revise as new science emerges or certainty increases

STORM SURGE: Science remains uncertain about future frequency and intensity Planning guidance: – Continue to plan for current storm frequency and intensity – Plan for greater flooding extent due to storm surge combined with sea-level rise – Update as new science emerges Science Advisory Panel Findings & Guidance

PRECIPITATION: Mean annual precipitation increase 10% from Annual precipitation in extreme events increased more than 50% from Mean annual precipitation and precipitation in extreme events projected to increase, but magnitude is uncertain Planning guidance – Use Cornell Northeast precipitation data for current projects – Plan for 15% increase in precipitation after 2050 – Update as new science emerges Science Advisory Panel Findings & Guidance

CRHC Guidance Scope of Interest – Assumptions RE sea level rise, flooding, precipitation, etc. – Economic impacts (business continuity, real estate, insurance) – Infrastructure (roads, bridges, telecomm, utilities, public facilities) – Ecosystem & Environment (salt marsh, groundwater) Dynamic and evolving information – Recognize explicitly that our findings are based on information and science that is still developing – implementation of recommendations should be phased and iterative allowing for “course corrections”

Types of Recommendations Municipal focus: – Recommended risk assumptions – Processes for building consensus for preparing for greater coastal flood risks – Models for implementation State agency focus: – General policies – New standards for design and construction – Infrastructure investment conditions – Coordination among agencies

WORKGROUPS State-Legislative Workgroup members assigned to report on: Existing regional adaptation strategies, legislation and executive orders Assessment and evaluation of vulnerabilities to state assets and resources Identifying legislative actions (first cut)

WORKGROUPS Inland-Great Bay Workgroup members assigned to report on background and technical documents: Georgetown Sea Level Rise Toolkit FEMA Mitigation Ideas and Community Rating System Vermont Law School Study (do statutes allow use of projected future climate data to regulate) Dover Climate Change Project & “Role Play” Simulation

WORKGROUPS Coastal Workgroup members assigned to summarize and report on: Results from questionnaire/survey of municipal staff, officials, boards Vermont Law School Study (do statutes allow use of projected future climate data to regulate) Input from regional stakeholders and practitioners from various workshops and outreach projects

CRHC General Timeline Fact FindingAssessment/EvaluationReporting & Outreach Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4 CRHC MeetingsXXX XX XXX XX XXX Science Advisory Panel ★ Sector Working Groups ★ Vulnerability Assessment ★ Other Research Eval. Responses/ Measures Devel. Recommendations Public Engagement Reports ★★★

Observations Made 1.Ours is the ‘first’ state level guidance in New Hampshire, not the last 2.Integrate risk tolerance into our recommendations 3.Recognize that the information we are using is dynamic 4.Most responses to coastal risks should be iterative 5.There is value is acting now to take advantage of ongoing rehab, reconstruction, redevelopment to better prepare the built environment, at less cost

More Information Website – via StormSmartCoasts NH (agendas, minutes, presentations, members roster, reports, resources)