Shoreline Change in Urban Massachusetts, Time for Retreat?

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  • Guy Billout, Civil Engineering

    Atlantic Monthly (2001) Shoreline Change in

    Urban Massachusetts:

    Time for Retreat?

    Porter Hoagland Marine Policy Center

    Woods Hole Oceanographic Institution

    Lisa Granquist

    Ph.D. Candidate Law & Public Policy

    Northeastern University

    AAAS February 2013

  • The ocean is huge, powerful, and eternal. Puny man can scarcely expect to win by overwhelming it, and anyone who counters its attack with brute-force solutions is doomed to expensive disappointment.

    Willard Bascom Waves and Beaches

    (1961)

    http://www.panoramio.com/photo/34182602 Minot Beach Community Scituate, MA 2010

  • Some Relevant Socio-economic Studies

    Sea-level rise (Yohe et al.): Normative

    Erosion risk (Kriesel et al.): Positive

    Also:

    Barrier alterations and vulnerability (McNamara, Werner) Beach nourishment between linked communities (Slott) Coordinated management of curved beaches (Jin, Ashton) Beaches and coastal property values (Landry, Pompe, Edwards) Optimal nourishment of beaches (Smith, Murray, Gopalakrishnan) Non-market values (Landry, Parsons, Whitehead)

  • Adaptation in the Face of Sea-Level Rise (Yohe et al.)

    Socially optimal timing:

    Delay

    Protect

    Abandon

    Sea Ranch, CA 2009

    Chatham, MA 2009 Springhill Beach Sandwich, MA 2008

    Springhill Beach Sandwich, MA 2008

    Massachusetts coastal

    urban areas

  • Urban Areas

    Urban areas comprise urbanized areas (UAs) and urban clusters (UCs)

    An urbanized area is an urban area of 50,000 or more people

    An urban cluster is an urban area of between 2,500 to 50,000 people

    Dark blue indicates 80-100% of the coastal Massachusetts population resides in urban areas (with the exceptions of Dukes and Nantucket counties)

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  • Massachusetts South Shore

    Combination of urbanized areas and urban clusters

    Hingham 22,157 Hull 10,293 Cohasset 7,542 Scituate 18,133 Marshfield 25,132 Duxbury 15,059 Kingston 12,629 Plymouth 56,468 Bourne 19,754 Sandwich 20,675 TOTAL 207,842 people

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  • Massachusetts Coastal Structures (n=3,767)

    Seawalls

    Revetments

    Groynes, Jetties

    Bulkheads

    Gabions

    Dune reconstructions

    Beach nourishments Source: MCZM

  • If the [coastal engineer] builds any new shoreline facilities that stop the flow of sand, there will be trouble both at the place where the sand stops and the place where it would have gone.

    Willard Bascom (1961)

    http://www.marineinsight.com/misc/marine-safety/a-barrier-with-a-difference-sea-walls/

    Sea walls are extremely utilitarian it becomes important to build such preventive structures in order to lessen the menace of natural calamities and to assure the people of their safety through a very visible, physically demonstrative and effective barrier.

    MarineInsight.com (2010)

  • Problems with Massachusetts Hard Structures

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    Attempting to halt the natural process of erosion with seawalls and other hard structures simply shifts the problem, subjecting downdrift property owners to similar losses.

    the undermining of sea walls, some of which are many decades old, can result in significant economic and emotional loss in a system of fixed property lines and ownership.

    Both quotes are from the Draft Old Colony Hazard Mitigation Plan (2012)

    Scituate, MA Winter Storm Nemo

    (February 2013)

  • MCZM now compiling data on vintages, conditions, repair costs

    Many gaps in the data

    Ownership (=> responsibility for maintenance) sometimes unclear

    Est. ~$700 million to repair

  • The Gurnet Plymouth, MA

  • Estimating Erosion Costs (Kriesel et al.)

    Data on the geographic position of shorelines over time => shoreline change rates

    Measure the distances from coastal properties to the shorelines

    Calculate the time to inundation for coastal properties

    Estimate the costs of erosion risks using hedonic pricing approaches

    20%

    30%

    40%

    50%

    60%

    70%

    80%

    90%

    100%

    0 10 20 30 40 50 60 70 80 90 100

    expected years away from the shoreline

    % o

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    Kriesel Atlantic 1978-1994 Linear Model 1952-2005 Linear Model

  • A Negotiated Solution? (Kriesel et al. 2000) Inland property owners

    observe significant premiums in home values due to the existence of beaches for recreation in front of proximate waterfront properties

    As erosion occurs, waterfront property owners seek to protect their properties with hard structures (seawalls, revetments)

    often waterfront property owners have the legal right to do this

    In theory, to protect their own home values, inland property owners could pay waterfront property owners to forego hard structural protections or to replenish sand on the beach

  • A Negotiated Solution in Massachusetts? But in Massachusetts, private property rights extend to

    mean low water (i.e., there is only very limited access by inland property ownersfishing and fowling)

    Hard structural responses are already widespread

    Wetlands Protection Act attempts to control hard structuring (but pre-existing structures, grandfathering, variances, illicit activity)

    Nevertheless, there may still be an externality due to the increased risks of erosion to properties adjacent to structures

    Consequently, there may be an opportunity for a negotiated solution among waterfront property owners

  • Harlows Landing Plymouth, MA

  • Harlows Landing Plymouth, MA

    Structure(s): 172 Revetment (with some seawall sections), built circa 1959(?); another structure attached and extending to the north

    Shorelines: Before: 1909, 1952 After: 1978, 1994

    Challenges: Accuracies of shoreline

    measurements Accelerated SLR?

  • Economic Effects

    Can estimate increased costs of risks faced by properties with no structures (both waterfront and inland) near waterfront properties with structures with Kriesel et al. approach (hedonic pricing models)

    Challenges:

    Data limitations (Shorelines, Structures, Vintages)

    Statewide problem?

    Public areas (Beaches, Wetlands)

  • Impacts on Natural Areas?

  • Potential Policy Solutions

    Uncertainty makes negotiated solutions problematic

    Retreat from the coast likely now optimal in many places

    1. FEMAs Hazard Mitigation Grant Program

    Purchase coastal properties and prohibit development

    State/Local Hazard Mitigation Plans Presidential declared disaster area Cost of repair > 50% of home value Must have willing sellers FEMA (75%); State/local (25%) Open space, recreation, or wetlands

    management

    2. NPSs reservations of use and occupancy

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  • Acknowledgements

    Funding:

    NSF/CNH

    WHOI Coastal Ocean Institute

    WHOI Marine Policy Center

    Data and Analysis: Andy Beet Jim OConnell Rob Thieler

    Other colleagues: Andrew Ashton Ilya Buynevich Jeff Donnelly Steve Eberbach Rob Evans Di Jin Hauke Kite-Powell Jorge Lorenzo-Trueba

    Slide Number 1Slide Number 2Some Relevant Socio-economic StudiesAdaptation in the Face of Sea-Level Rise(Yohe et al.)Urban AreasMassachusettsSouth ShoreMassachusetts Coastal Structures (n=3,767)Slide Number 8Problems with Massachusetts Hard StructuresSlide Number 10The GurnetPlymouth, MAEstimating Erosion Costs(Kriesel et al.)A Negotiated Solution? (Kriesel et al. 2000)A Negotiated Solution in Massachusetts?Harlows LandingPlymouth, MAHarlows LandingPlymouth, MAEconomic EffectsImpacts on Natural Areas?Potential Policy SolutionsAcknowledgements

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