Guy Billout, “Civil Engineering”

Atlantic Monthly (2001)

Shoreline Change in

Urban Massachusetts:

Erosion as Pollution?

Porter Hoagland Marine Policy Center

Woods Hole Oceanographic

Institution

Lisa Granquist Ph.D. Candidate

Law & Public Policy

Northeastern University

VIMS October 24, 2014

Acknowledgements

Funding:

• Northeast Sea Grant Consortium

• NSF/Coastal SEES

• NSF/CNH

• WHOI Coastal Ocean Institute

• WHOI Marine Policy Center

• Data and Analysis:

• Andy Beet

• Andy Fallon

• Jim O’Connell

• Rob Thieler

• Other colleagues:

• Andrew Ashton

• Ilya Buynevich

• Jeff Donnelly

• Steve Eberbach

• Rob Evans

• Di Jin

• Hauke Kite-Powell

• Jorge Lorenzo-Trueba

Outline

• Two analytical approaches

• Yohe et al.’s market-based adaptation to SLR

• Kriesel et al.’s empirical studies of erosion risk

• Massachusetts case: extensive coastal armoring

• Implications of armoring

• Erosion as pollution

• Future policies

“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, Smith, Murray)

• Coordinated management of curved beaches (Jin, Ashton, Hoagland)

• 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

t0* T*(t0*)

“Yohe Rule”

Delay Protect Abandon

0

)(

*0

VCAb

rFCt

b is the rate of sea-level rise

Inundation

$ Appreciation Depreciation

“Market-Based” Adaptation to Sea-Level Rise (Yohe et al.)

• ≤ 1m rise over the next century

• Decisions: delay (no action), protect, abandon

• Two main types of costs

• Protection (construction and maintenance)

• Abandoned land

• Market-based adaptation

• Economically rational “adaptation”

• Structures could depreciate with inundation “foresight”

• Society: waterfront “premium” is not lost

• US “true economic cost” of SLR: ~$300m per year

Optimal abandonment assumptions:

• good estimate of SLR rate

• assume society won’t step in to rescue

Woods Hole, MA 2008

Some Problems with Market-Based-Adaptation

• Subsidies (NFIP, ACoE)

• Incomplete information

• External effects of individual protection decisions

• Storms

• Public infrastructure (Plum Island)

→ Remove subsidies?

→ Science, insurance

→ Regulation (but variances often granted)

→ Pilings, setbacks, others

Shoreline Erosion Costs (Kriesel et al.)

• Analysis of the market for coastal housing

• Models the risk associated with shoreline change, while attempting to control for other factors affecting market price

• Asks: does the market incorporate information about the risk of coastal hazards—including SLR?

• Test of whether properties actually “depreciate” as the threat of shoreline change grows

Model of Housing Prices: PH = f (S,N,Q,ε)

• S = structural characteristics

• Land area

• Living area

• Number of bedrooms, bathrooms

• Type of construction

• Age of house

• Age of sale (market trends)

• N = neighborhood characteristics

• Quality of Schools

• Crime Rate

• Distance to Town Center

• Public transportation

• Roads

• Q = environmental

characteristics

• Waterfront property

• Beach width

• Distance to the coastline

• Erosion risk

• Flood risk

• Wind damage risk

• Beach nourishment

• Armoring

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

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100%

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alu

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

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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• 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

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 owners—navigation, fishing, 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

Harlow’s Landing Plymouth, MA

Harlow’s 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?

EROSION AS POLLUTION

• When a seawall is constructed, the

homes behind the seawall gain more

years prior to inundation

• This results in a benefit

• The unprotected homes downdrift

from the seawall approach lose years

prior to inundation

• This results in a cost

• A private decision relates to the

benefits of delayed inundation

relative to the cost of constructing the

seawall

• A social decision would include the

costs of increased erosion downdrift

Economic Effects

• The net effect depends upon:

• Erosion rates

• Property positions and values

• Construction costs

• Challenges:

• Data limitations (Shorelines, Structures, Vintages)

• Statewide problem?

• Public areas (beaches, wetlands, estuaries)

• Context:

• Environmental Bond

• Delayed Biggert-Waters

Impacts on Natural Areas?

Potential Policy Solutions

• Uncertainty makes negotiated solutions problematic

• Retreat from the coast likely now optimal in many places

1. FEMA’s 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. NPS’s “reservations of use and occupancy”

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