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
Kline Important Adjudicatory Decisions and Policy Direction 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
Frost Important Adjudicatory Decisions and Policy Direction 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
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. Primary Dunes
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 Amended in 2014 to provide a definition and boundary description of the primary dune to further clarify the importance of delineating this landform 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.
Find the inland limit of the primary dune MHW MHW
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. Geological science Defensible & Repeatable Quantitative analysis
Typical Ridge Type Dune OCEAN
POND Low-Volume Mound Type Dune OCEAN
Use Detailed Topographic Data: LIDAR MassGIS Data - LiDAR Terrain Data
Primary Dune Delineation
second derivative slope elevation (m) Are the peaks micro or macro-topography? If micro, select the next highest peak. 0.08 10 0.06 9 8 0.04 7 0.02 6 0 5-0.02 4-0.04 3 2-0.06 1-0.08 0 225 200 175 150 125 100 75 50 25 0 distance from shore (m)
elevation (m) Ground-truth all points? 10 9 8 7 6 5 4 3 2 1 225 200 175 150 125 100 distance from shore (m) 75 50 25 0 0
Definition Coastal Banks 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).
Future Source of Information Coastal Manual 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
Questions? Lealdon Langley - MassDEP lealdon.langley@state.ma.us 617-574-6882 Rebecca Haney - CZM rebecca.haney@state.ma.us 617-626-1228 Betsy Rickards - CZM betsy.rickards@state.ma.us 617-626-1214