Upload
lisa-granquist
View
588
Download
0
Tags:
Embed Size (px)
Citation preview
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
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
f 2
00
yr v
alu
e
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)
htt
p:/
/ww
w.c
en
su
s.g
ov/g
eo
/ww
w/m
ap
s/2
01
0_
ce
nsu
s_
UA
_m
ap
s/im
gs/U
A2
01
0_
Urb
an
_P
op
_M
ap
.pd
f
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
htt
p:/
/ww
w2
.ce
nsu
s.g
ov/g
eo
/ma
ps/d
c1
0m
ap
/UA
UC
_R
efM
ap
/ua
/ua
09
27
1_
bo
sto
n_
ma
--n
h--
ri/D
C10U
A0
92
71.p
df
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
ww
w.b
osto
nglo
be
.com
/metro
/20
13/0
2/0
9/lo
se
-po
wer-s
torm
-exp
ecte
d-c
on
tinu
e-in
to-m
idd
ay/1
I0rz
zS
PG
sdJ5
8jf0
LfF
IK/p
ictu
re.h
tml
htt
p:/
/ww
w.b
osto
n.c
om
/yo
urt
ow
n/s
citu
ate
/art
icle
s/2
01
1/0
5/2
9/s
citu
ate
_se
a_
wa
ll_re
pa
irs_
to_
be
_d
on
e_
in_
se
ve
ral_
cycle
s/
“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
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
• 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
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”
Bo
sto
n R
egio
n M
etro
po
lita
n P
lan
nin
g O
rgsa
niz
atio
n “
All
Haz
ard
s P
lan
nin
g”
htt
p:/
/ww
w.t
ow
n.s
citu
ate.
ma.
us/
flo
od
/Sci
tuat
e_H
azar
d_M
itig
atio
n_P
lan
.pd
f