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Protecting the Storm Damage
Prevention and Flood Control Interests
of Coastal Resource Areas
Presented by:
Massachusetts Department of Environmental Protection &
Massachusetts Office of Coastal Zone Management
Purpose of the Workshop
• Focus Area - Proposed projects that are likely to
affect the storm damage prevention and flood
control functions of coastal resource areas
• Important adjudicatory decisions and policy
direction
• Guidance for interpreting the existing coastal
wetlands regulations for delineation of coastal
dunes and coastal banks
FACT: Most of our coastline and coastal
resource areas are eroding
BEFORE AFTER
2011
Past Development Practices on
Coastal Resource Areas
• Inadequate to protect the
structures and ability of the
resource area to provide
flood control or storm
damage prevention
• Building elevations are
typically not allowing for
dune/bank migration or
growing vegetation
• No accounting for
shoreline retreat
• Economic losses for
homeowner
Inappropriately located dwellings and
infrastructure = costs to community
OVERWASH DESTROYS
ROAD
ROADS BECOME
IMPASSABLE
Inappropriately located dwellings
= costs for emergency response • Emergency orders
from conservation
commissions to allow
homeowners to
construct emergency
erosion barriers
• Police and DPW
response for public
safety to prevent public
access to areas with
severe erosion
• Public health dept. &
Building official
response to assess
building integrity
• Rescue personnel may
be put at risk
Important Adjudicatory Decisions
and Policy Direction
Peabody
New structure on undeveloped lot on primary dune
in V-Zone of barrier beach prohibited
• Would permanently alter 2000 sq ft of coastal dune
• Removal of vegetation cannot be mitigated at alternative
location and can cause erosion elsewhere
• Would interfere with landward or lateral migration of dune
Ocean
Site
Peabody
• All coastal dunes are likely to be significant to
storm damage prevention and flood control
and all coastal dunes on barrier beaches and
coastal dunes closest to beach are per se
significant to storm damage prevention (310
CMR 10.28(1))
• Because dunes on barrier beaches and the
coastal dune closest to the beach are singled
out as intrinsically important to storm damage
prevention and flood control, they warrant
greater scrutiny
Peabody
• Final Order upheld by Superior Court and
Massachusetts Appeals Court
• Short term accretion and erosion support
conclusion of inherent dune instability
• Dune accretion resulted from human
intervention
• Previous structure on property was removed in
1960 due to dune erosion
Important Adjudicatory Decisions
and Policy Direction
Kline
• 20 feet of fill placed on top of a barrier beach in
the 1870’s
– Definition of dune states “sediment deposited by
artificial means serving the purpose of storm damage
prevention and flood control” 310 CMR 10.28(2)
Site
Kline
• Does the fill function as a dune?
– Two way exchange of sediment with beach
– Landform can form and reshape in response to wind and
waves especially during a coastal storm
– Landform can migrate landward or laterally
• Decision found that artificial fill placed on the site
was functioning more like coastal bank than
coastal dune
• Functions like a coastal bank if it is clearly
landward of the 100-year floodplain and storm
water cannot wash over the top of the landform
and move sediments landward
Important Adjudicatory Decisions
and Policy Direction Frost
• Site contained large dune on top of a Coastal Bank
– Is it a Coastal Dune subject to regulation under the Act?
Example only
NOT the Frost Site
Frost
• Administrative Law Judge concluded that the dune
was a non-jurisdictional dune since it was
separated from the ocean by two wetland resource
areas—a coastal beach and a coastal bank
• A dune must either border the ocean or border
another wetland resource area that borders the
ocean in order for it to be an area subject to
protection under the Act.
Important Adjudicatory Decisions
and Policy Direction
Tzitzenikos
Located on
undeveloped
lot on the
primary frontal
dune of a
barrier beach
Site
Tzitzenikos
• Hearing Officer found project would not comply with
the Coastal Dune performance standards because it
would adversely impact:
1) the ability of the waves to remove sand from the dune
2) the landward or lateral movement of the dune
3) the vegetative cover, destabilizing the dune and
4) the site's ability to further the interests of preventing
storm or flood damage
• The primary dune methodology relied on by
MassDEP provided best available information and
was effective in delineating the landward toe of the
primary dune because it captured the entire dune
structure
Tzitzenikos
• Superior Court found that Hearing Officer did
not err by applying a federal standard to a
state requirement, but that state’s definition of
primary frontal dune was the same as federal
standard
• Superior Court found that the finding that the
site was within the primary dune was
supported by substantial evidence
• Superior Court found that the denial of the
project did not constitute an unconstitutional
taking of a private property
Important Adjudicatory Decisions
and Policy Direction
Bornstein
• Site was a low relief bank located adjacent to
salt marsh behind a barrier beach
• Hearing Officer found bank acted as both a
vertical buffer to wave action and as a source
of sediment
• Hearing Officer found the Coastal Bank was a
sediment source regardless of the volume of
sediment it provided
When Determining if a Coastal Bank is a
Sediment Source
Look for evidence that wave activity causes
erosion of a coastal bank
1) Must be a receiving landform, specifically a
beach, dune, or barrier beach, that is the recipient
of the sediment
2) Must be some current or historical evidence that
the bank is eroding or has eroded in the past
3) Coastal banks that are armored may provide
sediment if the area of the bank above the top of
the wall is subject to wave activity and can still
erode sediment from the bank
Implementing the WPA to reduce
storm damage and flooding
It is important to delineate all resource areas on a
site, then assess functions and determine if the
project complies with performance standards.
The guidance DEP and CZM developed has detailed
information on each of these three steps.
Focus today:
• Primary dune delineation
• Coastal Bank delineation
Primary Dunes
The regulations state that
all coastal dunes on
barrier beaches and the
coastal dune closest to the
coastal beach (primary
dune) are per se
significant to storm
damage prevention and
flood control.
Delineating Primary Dunes
• Primary frontal dunes (or primary dunes) are the first dune
landward of the coastal beach
• Peabody Decision: Dunes on barrier beaches and the coastal
dune closest to the beach are singled out as intrinsically
important to storm damage prevention and flood control = they
warrant greater scrutiny
• Use the primary dune delineation methodology based on
geological processes, topography, and a mathematical analysis
• Methodology was peer reviewed by a panel of coastal
geologists, FEMA technical consultants, FEMA staff and others
• Tzitzenikos Decision: Primary dune delineation methodology
relied on by MassDEP provided best available information and
was effective in delineating the landward toe of the primary
dune because it captured the entire dune structure
WPA Regulations
“a continuous or nearly continuous mound or ridge of sediment with relatively steep seaward and landward slopes immediately landward and adjacent to the beach and subject to erosion and overtopping from high tides and waves during coastal storms. The Primary Frontal Dune is the dune closest to the beach. The inland limit of the Primary Frontal Dune occurs at the point where there is a distinct change from a relatively steep slope to a relatively mild slope.”
Amended in 2014 to provide a definition and boundary
description of the primary dune to further clarify the
importance of delineating this landform
Find the inland limit of
the primary dune…
MHW
MHW
Geological
science
Quantitative
analysis
Breakdown of PFD Definition…
Primary frontal dune’ means a
continuous or nearly continuous
mound or ridge of sand with
relatively steep seaward and
landward slopes…subject to
erosion and overtopping from
high tides and waves during
major coastal storms.
The inland limit of the primary
frontal dune occurs at a point
where there is a distinct change
from a relatively steep slope to a
relatively mild slope.
Defensible &
Repeatable
Typical
Ridge
Type Dune
OCEAN
Low-Volume
Mound Type
Dune
POND
OCEAN
Use Detailed Topographic Data: LIDAR MassGIS Data - LiDAR Terrain Data
Primary Dune Delineation
Are the peaks micro or macro-topography?
If micro, select the next highest peak.
0
1
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10
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distance from shore (m)
ele
va
tio
n (
m)
-0.08
-0.06
-0.04
-0.02
0
0.02
0.04
0.06
0.08
se
co
nd
de
riv
ati
ve
slo
pe
0
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0255075100125150175200225
distance from shore (m)
ele
vati
on
(m
)
Ground-truth all points
?
Coastal Banks
Definition
Coastal Bank means the seaward face or side of
any elevated landform, other than a coastal
dune, which lies at the landward edge of a
coastal beach, land subject to tidal action, or
other wetland.
Coastal Banks
Delineation:
• Seaward edge (or bottom) of the coastal
bank begins at the toe of the coastal bank
slope, where other coastal wetland resource
areas end
• The landward edge (or top) of the coastal
bank is generally the top of, or the first major
break in, the face of the coastal bank.
• Note that a coastal bank is an “elevated
landform” so a coastal engineering structure
can not serve as a coastal bank.
Coastal Banks
• Delineation based on overall slope of landform and
not micro-topography or small incremental breaks
in slope
• In some cases, there may be a small break in slope,
which does not necessarily constitute the top of the
coastal bank
• There may be multiple coastal banks within the
same site, when they are separated by land subject
to coastal storm flowage (i.e., an area less than
10:1)
Approximate Scale: 1”=20’
Draw Transect Lines
• Draw transect lines perpendicular to all contour lines -
may not necessarily be straight lines
• Divide up transect into multiple segments – based on
lengths that appear to be uniform in slope
• If necessary take transect line “through” artificial features
to obtain overall landform
Determine Slopes for Each Segment
• Use ruler to measure
segments and scale to
the plan to find RUN
• Use contour lines to
determine RISE
• Depict as a ratio of
RUN:RISE
• The lower the ratio of
run (horizontal distance)
to rise (vertical
distance), the steeper
the slope (a 1:1 slope is
steeper than a 4:1
slope).
• Covers all coastal resource areas with storm damage
prevention or flood control interests
• Culmination of research, review, and input from the
best technical and regulatory advisors
• Includes delineation, function,
performance standards, case
scenarios
• Details primary dune delineation
• Includes adjudicatory and court
decisions
Future Source of Information –
Coastal Manual
Questions?
• Lealdon Langley - MassDEP
– 617-574-6882
• Rebecca Haney - CZM
– 617-626-1228
• Betsy Rickards - CZM
– 617-626-1214
