Lessons Learned and Best Practices: Resilience of Coastal Infrastructure Coastal Erosion Impact on Rincón Infrastructure Luis D. Aponte, Ph.D. P.E. luisd.aponte@upr.edu Professor University of Puerto Rico Miguel Canals, Ph.D. miguelf.canals@upr.edu Associate Professor Francisco Villafañe francisco.villafane@upr.edu Graduate student researcher March 9, 2017 College of Engineers and Surveyors of Puerto Rico Hato Rey, Puerto Rico
Agenda Introduction Site location Objective and motivation History of shoreline changes at Rincón Problems and solutions Vulnerable infrastructure Alternatives against coastal erosion Methodology Property cost analysis Cost-benefit ratio Effects of Hurricane Matthew Damage assessment site visit
Objective and Motivation Research LIFE CYCLE COST ANALYSIS OF BEACH RESTORATION: RINCÓN, PR TESTBED Provide a methodology to establish a cost-benefit ratio of beach nourishment vs. armoring the beach and managed retreat. Provide alternatives against the severe beach erosion that is compromising the infrastructure. Justify projects of beach restoration to develop the local economy.
NOAA Resilience Cycle Community resilience refers to the ability to adapt to changing conditions and withstand and rapidly recover from disruption due to emergencies. - Presidential Policy Directive/PPD-8: National Preparedness
Problems and Solutions Vulnerable Infrastructure Alternatives against coastal erosion
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Historical shoreline changes 1936 1983 1987 2007 2010 2016 Thieler et al., 2007 USACE Puerto Rico Planning Board Sea Grant UPRM
Alternatives Against Erosion Managed Retreat Armoring Beach Nourishment R. Chaparro Coastal Engineering Solutions
Managed Retreat Advantages No negative environmental impacts Maintains recreational value and use of beach Disadvantages Cost can be significant Limited by available of land for relocation Comparing Erosion Management Strategies in Waikiki, Hawai i R. Porro, 2015
Armoring Advantages Protects valuable coastal property Protects property against chronic erosion Disadvantages Results in loss of recreational value and use of beach Storm may exceed structure design capacity R. Chaparro Comparing Erosion Management Strategies in Waikiki, Hawai i R. Porro, 2015
Advantages Support tourism economy Increases coastal property values Beach Nourishment Long Branch NJ beach replenishment by NY District US Army Corps of Engineers Disadvantages Requires recurring maintenance ($$$) Limited to beach quality sand source Filmed by Bob Alberding / NJHeliPhoto.com Comparing Erosion Management Strategies in Waikiki, Hawai i R. Porro, 2015
Reinforced concrete wall Vinyl sheet piles
Type of protection Length (m) Boulders 841 Reinforced Concrete 328 Sheet piles 155 Manmade local design 2172 Natural protection 5475 Total 8.97 km
Methodology Property cost analysis (CRIM database) Cost-benefit ration (preliminary assessment)
Estimation of growth rate using CRIM data
Estimation of growth rate Data reduction Filtered data from 1993-2014 No. of property with sales information = 1911 F = P (1 + i) n Average growth rate = 5.76% σ = 1.40% F = future value P = present value i = growth rate n = number of periods 4.37% 5.76% 7.16%
Value of oceanfront properties impacted by proposed nourishment project 492 ocean front properties (Considered) ~5 km P 1958 = $ 6,402,020 i = 4.37% F 2016 = $ 79,851,366 F = P (1 + i) n F = future value P = present value i = growth rate n = number of periods Data source: Puerto Rico CRIM Office (Center for Municipal Revenue Collection)
Cost Benefit Ratio (CBR) CBR = Benefits Costs Beach Nourishment Unit cost: $20/m 3 Nourishment volume 1,000,000 m 3 Cost nourishment = $20/m 3 * 1,000,000 m 3 = $20,000,000 CBR nourishment = $79,851,355 $20,000,000 4 *CBR PRELIMINARY ASSESSMENT (Construction cost does not consider equipment mobilization)
Effects of Hurricane Matthew Rincón, PR
Matthew became a Category 5 hurricane at 13.3 degrees north, surpassing Hurricane Ivan as the southernmost hurricane of this intensity on record in the Atlantic basin. [2][1] [1] Philip Klotzbach [philklotzbach] (September 30, 2016). "#Matthew is the lowest latitude category 5 hurricane in the Atlantic on record (beating old record set by Ivan (2004))." (Tweet). Retrieved October 2, 2016 via Twitter. [2] Lixion Avila (September 30, 2016). Hurricane Matthew Discussion Number 12(Report). National Hurricane Center. Retrieved September 30, 2016.
500 nautical miles
On October 6, 2016 CariCOOS buoy at Rincón, P.R. measured waves with significant height of ~6ft @ 270⁰ and ~ 12 sec period Hurricane Matthew Other swell rounds (Oct. 4-18, 2016)
Weather.com
Matthew: first round Sept 27-29
Matthew: first round (Sept 27-29) Matthew @Ponce Buoy: 15 ft. Hs (26 ft. max)
Weather.com
Hurricane Matthew s 2 nd round: west-southwest swell Oct 4-6 2016 West-southwest swell, 6-8 @ 12-13 seconds
SWELL (periods > 10s) wave height and peak wave direction for Tuesday Oct 4 2016 @ 2PM
Villa Cofresí Hotel
Rincon Ocean Club 1 Sep-18-2016 Oct-6-2016
Oct-8-2016 Oct-14-2016
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