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1 Click to edit title style Samuel B. Merrill, PhD Jeffrey Western Ron Frazier September 16, 2015 Click to edit Master text styles Second level Third level Fourth level» Fifth level Benefit-Cost Analysis A Framework for Transportation Organizations

2 Northeast Extremes in 1-Day Precipitation

3 Spring_flood_risk.jpg

4 Flooding on the Red River in Minnesota

5 Surge from Hurricane Sandy crashes over a sea wall in Kennebunk, Maine on October 29, 2012

6 How to prioritize vulnerable assets? Ranking tools VAST Many state-level tools tailored to each individual setting e.g. Maine s Decision Support Tool (Judy Gates, Session 26)

7 But ranking doesn t get us there Still have important questions: Now what? Which design is best in this most important location? How much money does it make sense to spend here?

8 SLR Scenario Predictions for Portland, ME

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10 What is standard these days? NOAA Sea Level Rise viewer, Surgingseas.org Powerful visualizations and risk metrics Limit for BCA: not tied to local dollar values or actions

11 What is standard these days? NOAA Sea Level Rise viewer, Surgingseas.org Powerful visualizations and risk metrics Limit for BCA: not tied to local dollar values or actions ADCIRC and most other hydrologic modeling Detailed understanding of where water will go

12 Detailed water models are available, but

13 Detailed water models are available, but

14 Detailed water models are available, but

15 What is standard these days? NOAA Sea Level Rise viewer, Surgingseas.org Powerful visualizations and risk metrics Limit for BCA: not tied to local dollar values or actions ADCIRC and most other hydrologic modeling Detailed understanding of where water will go Limit for BCA: not tied to local dollar values or actions FEMA s HAZUS-MH Detailed analysis of damage from single events Limit for BCA: not cumulative; no gradual SLR; risk reduction comparisons are not possible FEMA s BCA toolkit Detailed analysis of real estate damage from single events Limit for BCA: Same as for HAZUS-MH; BCA, while strong, is per-building only. Not well-suited for transportation.

16 What is standard these days? NOAA Sea Level Rise viewer, Surgingseas.org Powerful visualizations and risk metrics Limit for BCA: not tied to local dollar values or actions ADCIRC and most other hydrologic modeling Detailed understanding of where water will go Limit for BCA: not tied to local dollar values or actions FEMA s HAZUS-MH Detailed analysis of damage from single events Limit for BCA: not cumulative; no gradual SLR; risk reduction comparisons are not possible FEMA s BCA toolkit Detailed analysis of real estate damage from single events Limit for BCA: Same as for HAZUS-MH; BCA, while strong for single buildings, is not well-suited for transportation.

17 The Framework Engineering Project Timeline Benefit-Cost Benefit-Cost Analysis Analysis $ Design $ Build $ Planning Preliminary Design Start Conceptual Design BCA

18 The Framework Engineering Project Timeline Conceptual Design BCA D1 D2 D3 Cumulative Avoided Damages Construction and Cumulative Repair Costs BCRs 5:1 1:1 0.2:1 25x savings

19 So what do we design for? 19

20 So what do we design for? A key measure of the value of any adaptation design investment is cumulative avoided damage

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22 Muskie School of Public Service University of Southern Maine Portland, Maine

23 Some Project Sites Completed or Underway Selsey, United Kingdom Santos, Brazil Fort Lauderdale, Florida Key Largo, Florida Islamorada, Florida Kingston, New York Piermont, New York Catskill, New York Groton/Mystic, Connecticut Hampton, New Hampshire Seabrook, New Hampshire Hampton Falls, New Hampshire East Machias, Maine Falmouth, Maine Portland, Maine Bowdoinham, Maine Old Orchard Beach, Maine Scarborough, Maine Bath, Maine Duxbury, Massachusetts Marshfield, Massachusetts Scituate, Massachusetts Duluth, Minnesota Rochester, Minnesota

24 Bridge Sensitivity to Elevated Water Levels View of a bridge over the Sandy River on ME-41 in Farmington, an example of the types of structures that have been evaluated with COAST software.

25 Maine 2014 FWHA Pilot Key elements: For each asset, the software analyzed benefitcost relationships of three alternatives: Replace in-kind Replace with structure built to 3.3 of SLR Replace with structure built to 6.6 of SLR In general: Costs: Initial replacement or construction costs. Maintenance and repair over time, after each surge event. Benefits: Avoided damages provided by each structure in the face of a range of SLR and surge scenarios cumulatively over time.

26 Depth Damage Functions Designed for Each Candidate Structure Elev. Damage Cost Extreme = $E/event Severe = $D/event 8-11 Moderate = $C/event 7-8 Minor = $B/event 0-7 Slight = $A/event Waterway Base Elevation

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29 Scarborough Low Sea Level Rise (3.3') Initial Construction Costs Total Damage/Repair Costs by 2100 TOTAL LIFE CYCLE COST BY 2100 Replace in Kind $3,600,000 $349,128 $3,949,128 Replace with 3.3' SLR design $4,300,000 $181,330 $4,481,330 Replace with 6' SLR design $6,000,000 $3,323 $6,003,323 Initial Construction Costs High Sea Level Rise (6') Total Damage/Repair Costs by 2100 TOTAL LIFE CYCLE COST BY 2100 Replace in Kind $3,600,000 $823,325 $4,423,325 Replace with 3.3' SLR design $4,300,000 $642,948 $4,942,948 Replace with 6' SLR design $6,000,000 $69,547 $6,069,547 Replace in Kind was the most cost effective choice for both Low and High sea level rise scenarios.

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31 Bath Low Sea Level Rise (3.3') Initial Construction Costs Total Damage/Repair Costs by 2100 TOTAL LIFE CYCLE COST BY 2100 Replace in Kind $400,000 $697,476 $1,097,476 Replace with 3.3' SLR design $594,000 $697,476 $1,291,476 Replace with 6' SLR design $1,000,000 $281,242 $1,281,242 Initial Construction Costs High Sea Level Rise (6') Total Damage/Repair Costs by 2100 TOTAL LIFE CYCLE COST BY 2100 Replace in Kind $400,000 $1,867,580 $2,267,580 Replace with 3.3' SLR design $594,000 $1,867,580 $2,461,580 Replace with 6' SLR design $1,000,000 $916,598 $1,916,598 Replace in Kind was the most cost effective choice for a Low sea level rise scenario, but Replace with 6 SLR design was the most cost effective choice for a High sea level rise scenario.

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33 Bowdoinham Low Sea Level Rise (3.3') Initial Construction Costs Total Damage/Repair Costs by 2100 TOTAL LIFE CYCLE COST BY 2100 Replace in Kind $250,000 $1,656,830 $1,906,830 Replace with 3.3' SLR design $394,000 $1,162,080 $1,556,080 Replace with 6' SLR design $491,000 $205,159 $696,159 Initial Construction Costs High Sea Level Rise (6') Total Damage/Repair Costs by 2100 TOTAL LIFE CYCLE COST BY 2100 Replace in Kind $250,000 $2,163,283 $2,413,283 Replace with 3.3' SLR design $394,000 $1,900,813 $2,294,813 Replace with 6' SLR design $491,000 $908,565 $1,399,565 Replace with 6 SLR design was the most cost effective choice for both Low and High sea level rise scenarios.

34 Minnesota DOT Example: Spring Valley Creek, Rochester

35 Projected Hydrologic Conditions 24-Hr Storm Return Period 2-yr storm 5-yr storm 10-yr storm 25-yr storm 50-yr storm 100-yr storm 500-yr storm Existing Discharge (cfs) Low Scenario Discharges (cfs) Medium Scenario Discharges (cfs) High Scenario Discharges (cfs) ,020 1,080 1,000 1,120 1,270 1,380 1,430 1,430 1,430 1,520 1,590 1,660 1,690 1,990 2,320 1,880 1,930 1,930 1,940 2,030 2,120 2,210 2,440 3,010 3,630 2,670 2,720 2,740 2,750 2,860 2,970 3,090 3,540 4,430 5,400 3,340 3,420 3,440 3,460 3,590 3,720 3,870 4,420 5,520 6,770 4,100 4,200 4,230 4,240 4,390 4,560 4,740 5,350 6,650 8,150 6,160 6,320 6,380 6,410 6,620 6,900 7,200 7,710 9,350 11,370

36 Option #1 Incremental improvement at the site. Add 2 6 x10 culverts. Widen stream channel. Maintain existing Culverts and roadway profile. Addresses inadequate conveyance.

37 Option # Improvements allow for 25-year storm to pass through facility (50-yr storm still overtops).

38 Option # Span 3.6 Rise Complete replacement and major site improvement New dual 32-foot span bridge Raise the roadway profile by 3.6-feet

39 Option #2 Provides 3-feet of clearance over the 50-year storm event for the moderate climate conditions in Span sized to meet current FEMA criteria Addresses 2 of 3 hydraulic impairments Undersized conveyance area Low lying roadway profile

40 Large Culvert #5722 Carrying US 63 over Spring Valley Creek 64 Option # Span 3.6 Rise Bridge Carrying US 16 over Spring Valley Creek Rise Holistic on-site and off-site improvements Replaces 47 bridge with a 70 Addresses all hydraulic impairments

41 Sample MN Results

42 And how to optimize across scenarios?

43 Framework Summary In terms of fiscal efficiency, there is no one right answer to the question what design standard should we use? Site-specific analysis is required.

44 The construction costs of seawall and road elevation are different for different states or situations, so the economic analysis should be conducted based on the actual construction plan in proposed locations.

45 Framework Summary In terms of fiscal efficiency, there is no one right answer to the question what design standard should we use? Site-specific analysis is required. Non-local, non structural elements can be incorporated into these BCAs, to reflect broad categories of agency costs.

46 Framework Summary In terms of fiscal efficiency, there is no one right answer to the question what design standard should we use? Site-specific analysis is required. Non-local, non structural elements can be incorporated into these BCAs, to reflect broad categories of agency costs. BCA for transportation structures should occur at the conceptual design stage, prior to launch of typical preliminary design efforts.

47 Final Points Asset-specific benefit-cost work Does not need to cost new money Does not need to be politically charged

48 Thank You! IMPLEMENTATION PLANNING Sam Merrill: Jeff Western: Image courtesy of Renjith Krishnan at FreeDigitalPhotos.net Ron Frazier: