environmental sensitivity index: rhode island

ENVIRONMENTAL SENSITIVITY INDEX: RHODE ISLAND
INTRODUCTION
Environmental Sensitivity Index (ESI) maps have been
developed for the marine and coastal areas of Rhode Island. The
ESI maps are a compilation of information from three main
categories: shoreline habitats; sensitive biological resources; and
human-use resources.
The individual map pages in this atlas are divided according
to the U.S. Geological Survey (USGS) topographic quadrangle
index. Black and white scanned images of these maps are used as
a backdrop for each map page in the atlas. The name and date on
the bottom right of each map page refer to the corresponding
USGS quadrangle and its publication or latest photorevision date.
SHORELINE HABITAT MAPPING
Original ESI maps, published in 1983, were re-examined and
fully updated using the sources and methods described below.
The intertidal shoreline habitats of Rhode Island were mapped
during overflights and ground surveys conducted by an
experienced coastal geologist in November of 1999. Preliminary
classification of portions of the shoreline near inlets was conducted
using black and white vertical aerial photography at a scale of
1:12,000 and color oblique photos taken from previous studies.
The overflights were conducted using an H-60 helicopter operated
by the U.S. Coast Guard, flying at elevations of 400-600 feet and
slow air speed. During this work, the ESI ranking of observed
intertidal shoreline habitats was denoted directly onto the
shoreline depicted on 1:24,000-scale USGS topographic maps.
Where appropriate, revisions to the existing shoreline were made
and where necessary, multiple habitats were described for each
shoreline segment. Basemaps used in the field were then scanned
using a large format scanner and shoreline classifications mapped
during the surveys were transposed onto the digital shorelines
provided by the Narragansett Bay Estuary Program (NBEP, a
program of the Rhode Island Department of Environmental
Management) and the RIGIS database of the University of Rhode
Island.
To determine the sensitivity of a particular intertidal shoreline
habitat, the following factors are integrated:
1) Shoreline type (substrate, grain size, tidal elevation, origin)
Each of the shoreline habitats are described on pages 7-12 in
terms of their physical description, predicted oil behavior, and
response considerations.
In addition to the field mapped ESI shoreline habitats, coastal
wetland habitat types as depicted on the maps come from data
provided by NBEP and RIGIS. These polygonal wetland types
were not checked or edited extensively as a part of this project.
One of the polygonal wetland types, freshwater scrub/shrub
wetlands, occurs mostly in inland areas, and therefore is not
generally considered part of the ESI shoreline classification. In
some cases, expert data providers and reviewers provided edits on
wetland location and extent. When provided, these changes were
incorporated in the atlas. Coastal wetland types depicted in this
atlas include:
•
Salt-Brackish Marshes
•
Freshwater Marshes
•
Freshwater Scrub/Shrub Wetlands
SENSITIVE BIOLOGICAL RESOURCES
Biological information presented in this atlas was collected,
compiled, and reviewed with the assistance of biologists and
resource managers from the Rhode Island Department of
Environmental Management (RIDEM), the U.S. Fish and Wildlife
Service (USFWS), the New England Aquarium, the RI Coastal
Resources Management Council (CRMC), the University of Rhode
Island, and other agencies, organizations, and groups (see the
acknowledgments). Information collected and depicted on the
maps denotes the key biological resources that are most likely at
risk in the event of an oil spill. Six major categories of biological
resources are included in this atlas: marine mammals, birds,
reptiles, fish, invertebrates, and habitats.
Polygons and points represent the spatial distribution of
biological resources on the maps. Associated with each of these
representations is an icon depicting the types of species or habitats
that are present. Species have been divided into groups and
subgroups, based on their behavior, morphology, taxonomic
classification, and spill vulnerability and sensitivity. The icons
below reflect this grouping scheme. The groups are color coded,
and different icons represent the subgroups:
2) Exposure to wave and tidal energy
3) Biological productivity and sensitivity
4) Ease of cleanup
Prediction of the behavior and persistence of oil in intertidal
habitats is based on an understanding of the dynamics of the
coastal environments, not just the substrate type and grain size.
The intensity of energy expended upon a shoreline by wave action,
tidal currents, and river currents directly affects the persistence of
stranded oil.
The need for shoreline cleanup activities is
determined, in part, by the slowness of natural processes in
removal of oil stranded on the shoreline. The potential for
biological injury and ease of cleanup of spilled oil are also
important factors in the ESI ranking. Generally speaking, areas
exposed to high levels of physical energy, such as wave action and
tidal currents, and low biological activity rank low on the scale,
whereas sheltered areas with associated high biological activity
have the highest ranking. The list below includes the shoreline
habitats delineated for Rhode Island, presented in order of
increasing sensitivity to spilled oil.
1A)
Exposed Rocky Shores
1B)
Exposed, Solid Man-made Structures
2A)
Exposed Wave-cut Platforms in Bedrock
3A)
Fine- to Medium-grained Sand Beaches
3B)
Scarps and Steep Slopes in Sand
4)
5)
Coarse-grained Sand Beaches
Mixed Sand and Gravel Beaches
6A)
Gravel Beaches
6B)
Riprap
7)
Exposed Tidal Flats
8A)
Sheltered Rocky Shores
8B)
Sheltered, Solid Man-made Structures
8C)
Sheltered Riprap
9A)
Sheltered Tidal Flats
9B)
Sheltered, Vegetated Low Banks
10A)
Salt- and Brackish-water Marshes
10B)
Freshwater Marshes
10D)
Scrub-Shrub Wetlands
The polygon color and pattern are generally the same for all
species in each major group (e.g., birds are green), and match the
icon colors. Also associated with each biological polygon or point
feature on the map is a resources at risk identification number
(RAR#), located under each icon or group of icons. The RAR#
references a table on the reverse side of the map with a complete
list of species associated with the polygon or point feature, and the
state and federal protected status (T&E), concentration,
seasonality, and life-history information for each species.
There are some species that are found throughout specific
geographical areas or habitat types on certain maps. Displaying
the polygons for these species would cover large areas or would
obscure the shoreline, ESI classification, or other biological
features, making the maps very difficult to read. Thus, species
which occur over the majority of certain geographic areas or
habitats are often identified in a small box on the maps which
states that they are “Present in ...” (e.g., “Present in Block Island
Sound” or “Present in Wetlands”). This approach informs the user
of the presence of these species, while maintaining readability of
the map. The use of this strategy is implemented on a map per
Rhode Island - Page 1
map basis, depending on the location, size, and number of
polygons present on each map.
MARINE MAMMALS
Marine mammals depicted in the Rhode Island atlas include
whales, dolphins, and seals. General distributions of cetaceans are
depicted on the maps, as specific concentration areas are not well
known. Known pupping and haul-out sites for seals are show on
the maps as polygons and points. Rhode Island Resource
Protection Project (RIRPP) seal haul-out and pupping information
was provided a 1996 digital point coverage, and by expert sources.
Other cetaceans were mapped based on interviews with local
resource experts from RIDEM, the New England Aquarium, and
Mystic Aquarium. Areas where seals are frequently sighted
swimming in coastal waters are designated by larger polygons.
Expert contacts for marine mammals in Rhode Island include:
April Valliere (DEM-Division of Fish & Wildlife (DF&W)),
401/782-4753; Greg Early (New England Aquarium), 617/9735246; and Rob Nawojchik (Mystic Aquarium), 860/572-5955.
Marine mammal areas are displayed on the maps as polygons
with a brown-hatched pattern or as brown points. In cases where
multiple resource types occupy the same polygon (such as sea
turtles and seals), a black-hatched multi-group pattern is used
rather than a brown-hatched pattern. A brown icon with a whale,
dolphin, or seal silhouette is used to indicate the presence of
marine mammals and is associated with all polygons containing
these resources.
The RAR# under the icon (or icon group) on the maps
references a table on the reverse side of the map. In this table, the
first column gives the species name. The second column indicates
whether the species is listed as threatened (T), endangered (E), or
special concern (S) on either the state and/or federal lists. The
next column provides an estimate of the concentration of the
species at the site. Concentration is usually represented as a
descriptive term, such as “uncommon”, “low”, “medium”, or
“high”. Descriptive concentrations are based on the opinion of
local resource managers or experts concerning relative
concentrations within the study area. In many cases, concentration
values have not been used, often because this level of information
is not known. Note that concentration should not be interpreted as
the “level of concern” or “importance” associated with a certain
site or particular resource.
The seasonality for each species or resource is shown in the
next twelve columns, corresponding to the months of the year. If a
species is present at a location in a particular month, an “X” is
placed in the month column. The final columns list the time
periods for sensitive life-history activities, such as pupping for
seals.
BIRDS
Birds in this atlas are divided into several species subgroups
based on taxonomy, morphology, behavior, and oil spill
vulnerability and sensitivity. The species table lists all the birds
included on the maps, sorted by subgroup. These species are
included either because of their likelihood of direct or indirect
impacts by an oil spill or similar incident, their general rarity or
imperilment, or their special protection status as threatened or
endangered. Rare/endangered species nesting sites, colonial
waterbird nesting colonies, osprey nesting sites, and migratory
waterfowl and shorebirds are especially emphasized. Colonial
waterbird and osprey nesting sites were based on 1992 and 1995
RIRPP data sets, respectively, and expert knowledge. Nesting and
concentration areas for rare/endangered species were based on
information provided by the RI Natural Heritage Program and
expert knowledge. General distribution and concentration areas
for many species were provided by the RIDEM and the USFWS.
An expert contact for osprey nesting sites is Lori Suprock
(DEM-DF&W), 401/789-7481. An expert contacts for waterfowl is
Charlie Allin (DEM-DF&W), 401-789-0281. An expert contact for
National Wildlife Refuge bird species is Charlie Vandemoer
(USFWS-Ninigret National Wildlife Refuge (NWR)), 401/364-9124.
An expert contact for colonial waterbirds and shorebirds is Chris
Raithel (DEM-DF&W), 401/789-7481. An expert contact for
threatened/endangered birds is Rick Enser (DEM-Natural
Heritage Program (NHP)), 401/222-2776 ext. 4308.
In several cases, general terms referring to species
assemblages, such as “shorebirds”, “waterfowl”, or “wading
birds” were included along with common names of individual
species, because it is possible that other species are present in
addition to the most common ones that were listed. In some cases,
these terms were used in place of individual species names
because the exact composition of the assemblages varies at many
locations.
Rhode Island – Page 2
Birds are shown on the maps as polygons with a greenhatched pattern. Osprey nest are shown as green points. Nests for
other bird species are typically shown as polygons, but are
occasionally depicted as points. In cases where multiple resource
types occupy the same polygon (such as birds and reptiles), a
black-hatched, multi-group pattern is used rather than a greenhatched polygon. A green icon (or icons) with the appropriate
subgroup silhouette(s) is used to indicate the presence of different
bird types (shorebirds, waterfowl, wading birds, etc.). The
appropriate icons are associated with all polygons containing
birds.
The RAR# under the icon (or icon group) on the maps
references a table on the reverse side of the map. In this table, the
first column contains the species common name. The second
column indicates whether the species is listed as threatened (T),
endangered (E), or special concern (S) on either the state (S)
and/or federal (F) lists. The next column provides an estimate of
the concentration of the species at the site. Concentration was
typically represented using a descriptive term, such as “very high”
or “high”, in Rhode Island. Concentration was sometimes
represented as the number of nests, breeding pairs, or birds in
Connecticut, and therefore maps along the state border may
include numeric concentrations for some species. Concentration
values have not been used if the information was not available.
Note that concentration should not be interpreted as the “level of
concern” or “importance” associated with a certain site or
particular resource. The seasonality for each species or resource is
shown in the next twelve columns, corresponding to the months of
the year. If a species or resource is present at a location in a
particular month, an “X” is placed in the month column. The last
four columns denote the nesting, laying, hatching, and fledging
time-periods for each species, if nesting occurs in the particular
area or site in question.
REPTILES
Reptiles depicted in the Rhode Island atlas include sea turtles
and diamondback terrapins. Resource experts from RIDEM, the
New England Aquarium, and the Mystic Aquarium provided
information on species distribution.
Expert contacts for sea turtles are: Greg Early (New England
Aquarium), 617/973-5246; and Rob Nawojchik (Mystic Aquarium),
860/572-5955. An expert contact for diamondback terrapins is
Chris Raithel (DEM-DF&W), 401/789-7481.
Reptiles are depicted as polygons with a red-hatched pattern.
In cases where multiple resource types occupy the same polygon, a
black-hatched, multi-group pattern is used rather than a redhatched polygon. A red icon with a turtle silhouette is used to
indicate the presence of reptiles, and is associated with all
polygons containing these resources.
The RAR# under the icon (or icon group) on the maps
references a table on the reverse side of the map. In this table, the
first column contains the species common name. The second
column indicates whether the species is listed as threatened (T),
endangered (E), or special concern (S) on either the state and/or
federal lists. The next column provides an estimate of the
concentration of the species at the site. Concentration is usually
represented as a descriptive term, such as “very rare”, “low”, or
“medium”. Descriptive concentrations are based on the opinion of
local resource managers or experts concerning relative
concentrations within the study area. Concentration values have
not been used because the information was not available. Note
that concentration should not be interpreted as the “level of
concern” or “importance” associated with a certain site or
particular resource.
The seasonality for each species or resource is shown in the
next twelve columns, corresponding to the months of the year. If a
species or resource is present at a location in a particular month, an
“X” is placed in the month column. The last columns denote
different life-history time-periods for reptiles, such as nesting,
hatching, juveniles, and adults.
FISH
Finfish depicted in this atlas include selected marine,
estuarine, and anadromous species. Species of commercial,
recreational, ecological, and/or conservation interest are
emphasized. Fish distributions are based largely on expert
opinion and incorporate a combination of resource survey data,
field experience, and habitat-based designations.
Expert contacts for marine and estuarine finfish are: Chris
Powell and Tim Lynch (DEM-DF&W), 401/294-4524; Dick
Satchwill and Jen Temple (DEM-Marine Fisheries); 401/783-2304.
An expert contact for anadromous fish is Bill Lapin (DEM-DF&W),
401/789-0281.
Estuarine, and marine fish species were mapped using broad
distributions on most maps. Some important spawning areas were
noted for key commercial species (i.e., winter flounder, tautog).
Anadromous species were mapped using arcs to delineate the
portions of rivers and streams where spawning occurs, and where
juveniles and adults are likely to pass through at some point
during their life cycles.
Marine and estuarine fish are shown on the maps as polygons
with a blue-hatched pattern. Blue arcs are used to designate
anadromous fish streams. In cases where multiple resource types
occupy the same polygon (such as fish and invertebrates), a blackhatched, multi-group pattern is used rather than a blue-hatched
polygon. A blue icon with a fish silhouette is used to indicate the
presence of fish. This icon is associated with all polygons or point
features containing fish.
The RAR# under the icon (or icon group) on the maps
references a table on the reverse side of the map. In this table, the
first column contains the species common name. The second
column indicates whether the species is listed as threatened (T),
endangered (E), or special concern (S) on either the state (S)
and/or federal (F) lists. The next column provides an estimate of
the concentration of the species at the site. Concentration is
usually represented as a descriptive term, such as “high” or “low”
for marine species, and “major” or “possible” for anadromous
runs. Descriptive concentrations are based on the opinion of local
resource managers or experts concerning relative concentrations
within the study area. In many cases, concentration values have
not been used, often at the request of data providers. Note that
concentration should not be interpreted as the “level of concern”
or “importance” associated with a certain site or particular
resource.
The seasonality for each species or resource is shown in the
next twelve columns, corresponding to the months of the year. If a
species or resource is present at a location in a particular month, an
“X” is placed in the month column. The last columns denote
different life-history time-periods for fish, including spawning,
eggs, larvae, juveniles, and adults.
INVERTEBRATES
Invertebrates depicted in this atlas include selected marine,
estuarine, and terrestrial species.
Species of commercial,
recreational, ecological, and/or conservation interest are
emphasized. Several known invertebrate concentrations, as well
as larger, more general areas where invertebrate habitat exists
were mapped. Invertebrate distributions are based largely on
expert opinion provided by the RIDEM. Natural Heritage
Program data were used to map occurrences of rare terrestrial
species.
Expert contacts for marine and estuarine invertebrates are:
Chris Powell and Tim Lynch, (DEM-DF&W), 401/294-4524; and
Dick Satchwill, (DEM-Marine Fisheries), 401/783-2304. An expert
contact for lobsters is Tom Angell, (DEM-Marine Fisheries),
401/783-2304. An expert contact for mollusks is Art Ganz, (DEMMarine Fisheries), 401/783-2304.
Invertebrates are shown on the maps as polygons with an
orange-hatched pattern. In cases where multiple resource types
occupy the same polygon (such as fish and invertebrates), a blackhatched multi-group pattern is used rather than an orange-hatched
polygon. An orange icon with the appropriate silhouette is used to
indicate the presence of different types of invertebrates (bivalves,
crabs, lobsters, etc.). This icon (or icon group) is associated with all
polygons or point features containing invertebrates.
The RAR# under the icon (or icon group) on the maps
references a table on the reverse side of the map. In this table, the
first column contains the species common name. The second
column indicates whether the species is listed as threatened (T),
endangered (E), or special concern (S) on either the state (S)
and/or federal (F) lists. The next column provides an estimate of
the concentration of the species at the site. Concentration is
usually represented as a descriptive term, such as “abundant”,
“moderate”, “mod/abund”, “high”, or “medium”. Descriptive
concentrations are based on the opinion of local resource managers
or experts concerning relative concentrations within the study
area. In many cases, concentration values have not been used,
often at the request of data providers. Note that concentration
should not be interpreted as the “level of concern” or
“importance” associated with a certain site or particular resource.
The seasonality for each species or resource is shown in the
next twelve columns, corresponding to the months of the year. If a
species or resource is present at a location in a particular month, an
“X” is placed in the month column. The last columns denote
different life-history time-periods for invertebrates, including
spawning, eggs, larvae, juveniles, and adults.
HABITATS
Three types of habitats were mapped for Rhode Island: 1)
eelgrass beds, 2) macroalgae, and 3) rare/endangered coastal
terrestrial plants. These resources were mapped using a variety of
data sources and methods. The following digital coverages were
used to depict eelgrass data: 2000 URI Natural Resources Science
eelgrass polygons for Ninigret Pond; 2000 URI Graduate School of
Oceanography (GSO) eelgrass polygons for Ninigret Pond; 2000
URI/GSO eelgrass polygons for Quonochontaug Pond; 2000
Coastal Resources Management Council (CRMC/RIDEM) eelgrass
polygons; 2000 RIDEM Department of Fish & Wildlife eelgrass
points; 1996 Narragansett Bay Estuary Program (NBEP) eelgrass
polygons; and 1991 Applied Science Associates (ASA) eelgrass
polygons. These data were all compiled onto USGS topo quads
and reviewed by resource experts from several RIDEM and URI
departments and programs who supplemented the existing data
with field knowledge. In areas where data from multiple sources
overlapped but were not consistent with one another, the polygons
covering the largest area of water were used, as to err towards
protection of the resource.
Macroalgae distributions were based on 1991 ASA macroalgae
polygons. Threatened/endangered plant locations were provided
by the RI Natural Heritage Program.
Expert contacts for eelgrass are: Chris Deacutis, (DEM-NBEP),
401/222-4700 ext. 7270; Helen Cottrell, (DEM-NBEP), 401/2223961; Laura Ernst, (DEM-CRMC), 401/783-3370; Chris Powell and
Tim Lynch (DEM-DF&W), 401/294-4524; and Art Ganz, (DEMMarine Fisheries), 401/783-2304.
An expert contact for
threatened/endangered plants is Rick Enser, (DEM-NHP),
401/222-2776 ext. 4308.
Eelgrass and macroalgae are depicted on the maps using two
different purple “simplified-wetland” patterns for the different
vegetation types. No icons or RAR#s are used for the benthic
habitats, in order to simplify the maps.
Plants are depicted as polygons shaded with a purple-hatched
pattern. In cases where multiple resource types occupy the same
polygon (such as plants and invertebrates), a black-hatched multigroup pattern is used rather than a purple-hatched polygon. A
purple icon with the appropriate silhouette is used to indicate the
presence of plant resources. This icon (or icon group) is associated
with all polygons containing plants.
The RAR# under the icon (or icon group) on the maps
references a table on the reverse side of the map. In this table, the
first column contains the species common name. The second
column indicates whether the species is listed as threatened (T),
endangered (E), or special concern (S) on either the state (S)
and/or federal (F) lists. The next column provides an estimate of
the concentration of the species at the site. Concentration values
have not been used, because the information is not available.
The seasonality for each species or resource is shown in the
next twelve columns, corresponding to the months of the year. If a
species or resource is present at a location in a particular month, an
“X” is placed in the month column. All plant resources are shown
as present all year in this atlas.
HUMAN-USE RESOURCES
Most human-use resources in this atlas are mapped as point
features, indicated by a black and white icon (see legend).
Management areas such as wildlife refuges, state parks, state
forests, etc. are mapped as polygons, with the boundaries
indicated as a black dot-dash line with the corresponding icon
placed near the center of the polygon. Where the feature is a
known point location (e.g., water intake, boat ramp, marina), the
exact location is shown as a small black dot and a leader line is
drawn from it to the icon. Recreational beaches, archaeological
sites, etc. are indicated by an icon placed in the general area,
without any points or polygons, since the boundaries for these
resources are not readily defined.
Airport: Locations of airports, airfields, landing strips, helipads
etc., whether they are manned or unmanned. This information
was gathered from published maps and atlases.
Aquaculture: Locations of aquaculture sites. When known, the
site name, owner/manager, and contact information are provided
on the data tables for each map. This information was provided by
RIDEM, Marine Fisheries
Rhode Island - Page 3
SHORELINE CLASSIFICATIONS
The ESI shoreline habitat classification is stored as lines and
polygons with associated attributes. In many cases, a shoreline
may have two or three different classifications. These multiple
classifications are represented on the maps by double and triple
line patterns and in the database by ESI#1/ESI#2, where ESI#1 is
the landward-most classification and ESI#2 is the seaward-most
classification. In addition to the line features, exposed wave-cut
platforms (ESI = 2A), tidal flats (ESI = 7, ESI = 9A), marshes
(ESI=10A, ESI=10B), swamps (ESI=10C), and Scrub-Shrub
Wetlands (ESI = 10D) are also stored as polygons.
SENSITIVE BIOLOGICAL RESOURCES
Archaeological/Historical Site: Location of archaeological and
historic sites for coastal areas. These resources include known and
potential archaeological/historical sites documented by the State
Historic Preservation and Heritage Commission (RIHPHC). The
exact location and extent of these sites are not represented on the
maps due to their sensitivity to disturbance and vandalism,
instead, sites are depicted on the maps with an icon placed in the
general vicinity of the site (or group of sites). This information was
provided by the RIHPHC. For more specific site information and
guidance during planning and response operations, contact Dr.
Paul Robinson or Charlotte Taylor at 401-222-2678.
Boat Ramp: Locations of boat ramps. This information was
gathered from overflight observations, aerial photographs, and a
digital point coverage provided by the RIGIS Program.
Commercial Fishing: Locations of commercial fishing sites. This
information was provided by RIDEM, Marine Fisheries.
Ferry: Locations of ferry landings.
Marine Sanctuary: Location of the Naragannsett Bay National
Estuarine Research Reserve (NERR) managed by NOAA. This
information was gathered from a digital polygon coverage
provided by the RIGIS Program.
Marina: Location of marinas. This information was gathered from
overflight observations, aerial photographs, and a digital point
coverage provided by the RIGIS Program.
Recreational Beach: Locations of recreational beaches used for
activities such as swimming, sun-bathing, boating, picnicking, etc.
Water activities and use of recreational beaches may occur along
all shoreline areas where access is possible. This information was
gathered from published atlases and local resource managers.
State/Regional Park: Locations of areas managed by the State
Parks and Recreation Division as state parks, state forests, and
related properties. Property names are provided in the data tables
for each map. This information was gathered from a digital
polygon coverage provided by the RIGIS Program.
Washover site: Locations of sites along the coast where tidal
waters may overwash the land surface forming non-permanent or
ephemeral connections to tidal creeks, steams, and coastal ponds
etc. Overwash is particularly common at these sites during storm
events.
The washover sites were mapped as part of the
overflights. In some cases they were interpreted from the USGS
topographic basemaps.
Water Intake: Locations of surface water intakes. When known,
the site name, owner/manager, and telephone number are
provided on the data tables for each map. This information was
provided by the U.S. Coast Guard, Marine Safety Office,
Providence, Rhode Island.
Wildlife Refuge/Management Area: Areas managed by the
USFWS as National Wildlife Refuges, and other management areas
managed by the RIDEM. Site names are provided on the data
tables for each map.
GEOGRAPHIC INFORMATION SYSTEM
The entire atlas product is stored in digital form in a
Geographic Information System (GIS) as spatial data layers and
associated databases. The format for the data varies depending on
the type of information or features for which the data are being
stored.
Under separate cover is a metadata document which details
the data dictionary, processing techniques, data lineage, and other
descriptive information for the digital data sets and maps that
were used to create this atlas. Below is a brief synopsis of the
information contained in the digital version. Refer to the metadata
file for a full explanation of the data and its structure.
Rhode Island – Page 4
Biological resources are stored as polygons, arcs, or points.
Associated with each feature is a unique identification number that
is linked to a series of data tables that further identify the
resources. The main biological resource table consists of a list of
species identification numbers for each site, the concentration of
each species at each site, and identification codes for seasonality
and source information. This data table is linked to other tables
that describe the seasonality and life-history time-periods for each
species (at month resolution) for the specified map feature. Other
data tables linked to the first table include:
the species
identification table, which includes common and scientific names;
the species status table, which gives information for state and/or
federal threatened or endangered listings; and the source database,
which provides source metadata at the feature-species level
(specific sources are listed for each species occurring at each
mapped feature in the biology coverages).
HUMAN-USE FEATURES
Human-use features are represented as lines, points, or
polygons. The resource name, the owner/manager, a contact
person, and phone number are included in the database for
management areas, water intakes, and aquaculture sites when
available. All metadata sources are documented at the feature
level.
REFERENCES
Listed below are the major hardcopy reference materials used
during this project.
Able, K.W. and M.P. Fahay. 1998. The First Year in the Life of
Estuarine Fishes in the Middle Atlantic Bight. Rutgers
University Press, New Brunswick, NJ. 342 p.
Conway, R.A. 1992. Field checklist of Rhode Island birds. Bull.
No. 1. Audubon Society of RI, Smithfield, RI, 18 p.
Delorme. 1999. Connecticut/Rhode Island Atlas & Gazetteer.
Delorme, Yarmouth, ME. 80 p.
Stone, S.L., T.A. Lowery, J.D. Field, C.D. Williams, D.M. Nelson,
S.H. Jury, M.E. Monaco, and L. Andreasen. 1994. Distribution
and abundance of fishes and invertebrate in Mid-Atlantic
estuaries.
ELMR Rep. No. 12.
NOAA/NOS Strategic
Environmental Assessments Division, Silver Spring, MD. 280
p.
Wynne, K. and M. Schwartz. 1999. Guide to Marine Mammals &
Turtles of the U.S. Atlantic and Gulf of Mexico. Rhode Island
Sea Grant, Narragansett, RI. 114 p.
ACKNOWLEDGMENTS
This project was supported by the NOAA Office of Response
and Restoration, Hazardous Materials Response Division. Steve
Lehmann, NOAA SSC, assisted greatly in all aspects of the
project’s completion.
The biological and human-use data included on the maps were
provided by numerous individuals and agencies. Rhode Island
Department of Environmental Management staff from several
divisions and programs, particularly the Division of Fish and
Wildlife, Marine Fisheries, the Natural Heritage Program, the
Coastal Resources Management Council, the Narragansett Bay
Estuary Program, and the Rhode Island Historic Preservation and
Heritage Commission contributed a vast amount of information to
this effort, including first-hand expertise, publications, reports,
maps, and data. Other agencies and organizations contributing to
data development and review included: U.S. Fish and Wildlife
Service, University of Rhode Island, Graduate School of
Oceanography, and the URI Natural Resources Science
Department, the New England Aquarium, Mystic Aquarium, and
the U.S. Coast Guard.
At Research Planning, Inc. (RPI) of Columbia, South Carolina,
numerous scientific, GIS, and graphic staff were involved with
different phases of the project. Scott Zengel was Project Manager.
Shoreline habitat mapping was conducted by Miles O. Hayes and
Colin Plank. The biological and human-use data were collected
and compiled onto base maps by Christine Lord. Chris Locke (GIS
Project Coordinator), Jon Whitlock, and Vermell Simon Pyatt
entered, processed, and produced the GIS data and hardcopy atlas
under the supervision of Mark White, GIS Director. Graphic art
production was conducted by Joe Holmes. Becky Cox and Kristi
Suggs prepared the final text documents and metadata.
APPROPRIATE USE OF ATLAS AND DATA
This atlas and the associated database were developed to
provide summary information on sensitive natural and human-use
resources for the purposes of oil and chemical spill planning and
response. Although the atlas and database should be very useful
for other environmental and natural resource planning purposes, it
should not be used in place of data held by the RIDEM Division of
Fish and Wildlife, RI Natural Heritage Program, RI Coastal
Resources Management Council, RIDEM Narragansett Bay
Estuary Project, RI Historical Preservation and Heritage
Commission, USFWS, University of Rhode Island Graduate School
of Oceanography, URI Natural Resources Science, or other
agencies. Likewise, information contained in the atlas and
database cannot be used in place of consultations with natural and
cultural resource agencies, or in place of field surveys. Also, this
atlas should not be used for navigation.
Rhode Island - Page 5
SPECIES LIST
Common Name *
Species Name *
Common Name *
MARINE MAMMAL
BIRD cont.
DOLPHIN
Atlantic white-sided dolphin
Harbor porpoise
Saddle-backed dolphin
WATERFOWL cont.
Waterfowl
White-winged scoter
Wood duck
PINNIPED
Gray seal
Harbor seal
Harp seal
Hooded seal
Seals
WHALE
Humpback whale
Minke whale
Northern right whale
Lagenorhynchus acutus
Phocoena phocoena
Delphinus delphis
Halichoerus grypus
Phoca vitulina
Pagophilus groenlandicus
Cystophora cristata
Megaptera novaeangliae
Balaenoptera acutorostrata
Eubalaena glacialis
BIRD
FISH
Alewife
American eel
American sand lance
American shad
Anadromous fish
Atlantic herring
Atlantic mackerel
Atlantic menhaden
Atlantic salmon
Atlantic sturgeon
Bay anchovy
Black sea bass
Blueback herring
Bluefish
Brown trout (sea run)
Butterfish
Cunner
Gizzard shad
Hickory shad
Rainbow smelt
Scup (porgy)
Shortnose sturgeon
Skates
Striped bass
Summer flounder
Tautog
Weakfish
White perch
Windowpane flounder
Winter flounder
Gavia immer
Phalacrocorax auritus
Podiceps auritus
Podilymbus podiceps
Gavia stellata
GULL/TERN
Common tern
Great black-backed gull
Herring gull
Least tern
Roseate tern
Sterna hirundo
Larus marinus
Larus argentatus
Sterna antillarum
Sterna dougallii
PASSERINE
Saltmarsh sharp-tailed sparrow
Seaside sparrow
Whip-poor-will
Yellow-breasted chat
Ammodramus caudacutus
Ammodramus maritimus
Caprimulgus vociferus
Icteria virens
RAPTOR
Osprey
Pandion haliaetus
REPTILE
Haematopus palliatus
Charadrius melodus
Calidris maritima
TURTLE
Diamondback terrapin
Green sea turtle
Kemp's ridley sea turtle
Leatherback sea turtle
Loggerhead sea turtle
WADING BIRD
American bittern
Black rail
Black-crowned night heron
Clapper rail
Glossy ibis
Great egret
Green heron
King rail
Least bittern
Little blue heron
Snowy egret
Sora
Wading birds
Yellow-crowned night heron
WATERFOWL
American black duck
American coot
American wigeon
Black (common) scoter
Blue-winged teal
Brant
Bufflehead
Canada goose
Canvasback
Common eider
Diving ducks
Gadwall
Greater scaup
Green-winged teal
Harlequin duck
Hooded merganser
Lesser scaup
Mallard
Mute swan
Red-breasted merganser
Ring-necked duck
Ruddy duck
Sea ducks
Surf scoter
Rhode Island - Page 6
Catoptrophorus semipalmatus
Botaurus lentiginosus
Laterallus jamaicensis
Nycticorax nycticorax
Rallus longirostris
Plegadis falcinellus
Ardea alba
Butorides virescens
Rallus elegans
Ixobrychus exilis
Egretta caerulea
Egretta thula
Porzana carolina
Nyctanassa violacea
Anas rubripes
Fulica americana
Anas americana
Melanitta nigra
Anas discors
Branta bernicla
Bucephala albeola
Branta canadensis
Aythya valisineria
Somateria mollissima
Anas strepera
Aythya marila
Anas crecca
Histrionicus histrionicus
Lophodytes cucullatus
Aythya affinis
Anas platyrhynchos
Cygnus olor
Mergus serrator
Aythya collaris
Oxyura jamaicensis
Melanitta perspicillata
Melanitta fusca
Aix sponsa
FISH
DIVING BIRD
Common loon
Double-crested cormorant
Horned grebe
Pied-billed grebe
Red-throated loon
SHOREBIRD
American oystercatcher
Piping plover
Purple sandpiper
Shorebirds
Willet
Species Name *
Alosa pseudoharengus
Anguilla rostrata
Ammodytes americanus
Alosa sapidissima
Clupea harengus
Scomber scombrus
Brevoortia tyrannus
Salmo salar
Acipenser oxyrinchus
Anchoa mitchilli
Centropristis striata
Alosa aestivalis
Pomatomus saltatrix
Salmo trutta (sea run)
Peprilus triacanthus
Tautogolabrus adspersus
Dorosoma cepedianum
Alosa mediocris
Osmerus mordax
Stenotomus chrysops
Acipenser brevirostrum
Morone saxatilis
Paralichthys dentatus
Tautoga onitis
Cynoscion regalis
Morone americana
Scophthalmus aquosus
Pleuronectes americanus
Malaclemys terrapin
Chelonia mydas
Lepidochelys kempii
Dermochelys coriacea
Caretta caretta
INVERT
BIVALVE
Atlantic surfclam
Blue mussel
Eastern oyster
Northern quahog (hard clam)
Softshell clam
Spisula solidissima
Mytilus edulis
Crassostrea virginica
Mercenaria mercenaria
Mya arenaria
CEPHALOPOD
Longfin squid
Loligo pealeii
CRAB
Blue crab
Horseshoe crab
Callinectes sapidus
Limulus polyphemus
INSECT
Claybanks tiger beetle
Saltmarsh tiger beetle
Cicindela limbalis
Cicindela marginata
LOBSTER
American lobster
Homarus americanus
HABITAT
PLANT
Endangered plant
Rare plant
Threatened plant
Sea-beach knotweed
Eastern gamagrass
Freshwater tidal marsh
Sea level fen
Sea pink
Whorled milkwort
Polygonum glaucum
Tripsarum dactyloides
Sabatia stellaris
Polygala verticillata
* Threatened and endangered species and species of special
concern are designated by underlining
SHORELINE DESCRIPTIONS
EXPOSED ROCKY SHORES
ESI = 1A
DESCRIPTION
•
The intertidal zone is steep (greater than 30° slope), with
very little width; solid and composed of bedrock
•
Sediment accumulations are uncommon because waves
remove the debris that has slumped from the eroding cliffs
•
There is strong vertical zonation of intertidal biological
communities
•
This shoreline type is regularly exposed to wave action and
strong currents
•
Wave reflection is a common phenomena along these
shorelines
•
Attached organisms are accustomed to the impacts of the
waves and the associated hydraulic pressure
•
Species density and diversity vary greatly, but barnacles,
snails, mussels, polychaetes, and macroalgae are abundant
in places
•
They are common along the outer coast of Rhode Island, the
south western shores of Narragansett Bay, and near
Branford, Connecticut
PREDICTED OIL BEHAVIOR
The most resistant oil would remain as a patchy band at or
above the high-tide line
•
Impacts to intertidal communities are expected to be shortterm in duration. An exception would be where heavy
concentrations of a light refined product comes ashore very
quickly
RESPONSE CONSIDERATIONS
•
Oil is held offshore by waves reflecting off the steep, hard
surfaces
•
Any oil that is deposited is rapidly removed from exposed
faces
EXPOSED, SOLID MAN-MADE STRUCTURES
•
•
Cleanup is usually not required
•
Access can be difficult and dangerous
ESI = 1B
DESCRIPTION
•
These structures are solid, man-made structures such as
seawalls, groins, revetments, piers, and port facilities
•
Many structures are constructed of concrete, wood, or metal
•
Often there is no exposed substrate at low tide, but multiple
habitats are indicated if present
•
They are built to protect the shore from erosion by waves,
boat wakes, and currents, and thus are exposed to rapid
natural removal processes
•
Attached animals and plants are sparse to moderate
•
They are common throughout the study area, in both highly
developed commercial zones such as Newport and
Providence Harbor, and residential waterfronts.
PREDICTED OIL BEHAVIOR
RESPONSE CONSIDERATIONS
•
Oil is held offshore by waves reflecting off the steep, hard
surface in exposed settings
•
Oil readily adheres to the dry, rough surfaces, but it does not
adhere to wet substrates
•
The most resistant oil would remain as a patchy band at or
above the high-tide line
EXPOSED WAVE-CUT PLATFORMS IN BEDROCK
•
Cleanup is usually not required
•
High-pressure water spraying may be conducted to:
- remove persistent oil in crevices;
- improve aesthetics; or
- prevent leaching of oil
ESI = 2A
DESCRIPTION
•
They are characterized by a narrow shelf or platform that
can be flooded depending on water levels
•
The substrate is solid and portions of the platform may be
covered by a relatively thin veneer of sand or gravel
•
The surface of the platform is irregular and the presence of
tidal pools is common
•
Species density and diversity varies greatly, but barnacles,
snails, mussels, polychaetes, and macroalgae are often very
abundant
•
Attached organisms are accustomed to the impacts of the
waves and the associated hydraulic pressure
•
They are very common throughout the study area, often
found with gravel and mixed sediment beaches along the
high tide line. They are also common at the foot of exposed
rocky shores. On Block Island they occur as wave cut till
platforms consisting of highly irregular boulder and cobble
surfaces
PREDICTED OIL BEHAVIOR
•
Oil will not adhere to the wet rock surface, but could
penetrate crevices, sediment veneers or associated beaches if
present
•
Persistence of oil is usually short-term, except in wave
shadows or where the oil was deposited high above normal
wave activity
RESPONSE CONSIDERATIONS
•
Cleanup is usually not required except for areas of high
recreational use
•
Where the high-tide area is accessible, it may be feasible to
manually remove heavy oil accumulations and oiled debris
Rhode Island – Page 7
FINE- TO MEDIUM-GRAINED SAND BEACHES
ESI = 3A
DESCRIPTION
•
These beaches are flat to moderately sloping and relatively
hard packed
•
They are composed of predominantly quartz sand
•
There can be heavy accumulations of wrack present
•
They are utilized by birds and turtles
•
Upper beach fauna include ghost crabs and amphipods;
lower beach fauna can be moderate, but highly variable
•
They are present along the Atlantic coast and grade laterally
into coarse grained beaches. They are generally areas of
recreational use such as Sand Hill Cove State Beach
PREDICTED OIL BEHAVIOR
•
Light oil accumulations will be deposited as oily swashes or
bands along the upper intertidal zone
•
RESPONSE CONSIDERATIONS
•
These beaches are among the easiest shoreline types to clean
Heavy oil accumulations will cover the entire beach surface;
oil will be lifted off the lower beach with the rising tide
•
Cleanup should concentrate on removing oil and oily debris
from the upper swash zone once oil has come ashore
•
Maximum penetration of oil into fine- to medium-grained
sand is about 10-15 cm
•
Traffic through both oiled and dune areas should be severely
limited, to prevent contamination of clean areas
•
Burial of oiled layers by clean sand within the first week
after a spill typically will be less than 30 cm along the upper
beach face
•
Manual cleanup, rather than road graders and front-end
loaders, is advised to minimize the volume of sand removed
from the shore and requiring disposal
•
Organisms living in the beach sediment may be killed by
smothering or lethal oil concentrations in the interstitial
water
•
All efforts should focus on preventing the mixture of oil
deeper into the sediments by vehicular and foot traffic
•
•
Biological impacts include temporary declines in infauna,
which can affect important shorebird foraging areas
Mechanical reworking of lightly oiled sediments from the
high-tide line to the upper intertidal zone can be effective
along outer beaches
SCARPS AND STEEP SLOPES IN SAND
ESI = 3B
PREDICTED OIL BEHAVIOR
DESCRIPTION
•
Bluffs and scarps of fine to medium grained sand are
typically associated with undeveloped inlets and the cut
banks of meandering rivers and tidal creeks
•
May be associated with narrow beaches where erosion is
episodic or is occuring at a moderate rate
•
Tops of scarps and slopes may be vegetated with grasses,
scrub-shrub vegetation, or trees all of which are eventually
undercut by the retreating shoreline, resulting in a collection
of woody debris at the high tide line.
•
Uncommon in study area at the time of overflights, these
shoreline types may develop on any erosional coastline
COARSE-GRAINED SAND BEACHES
•
Stranded oil may accumulate at the high tide line, possibly
penetrating sandy sediments
•
Slight potential for burial exists due to erosional nature of
the slope or scarp
•
Oil may adhere to dry surfaces of the woody debris at the
base of the slope or scarp
RESPONSE CONSIDERATIONS
•
Cleanup is usually not required, because oil is quickly
removed by wave action
•
Access may be difficult and dangerous; crews must be
mindful of slope instability
•
The need for the removal of oiled sediments and debris
should be carefully evaluated because of the potential for
increased erosion
ESI = 4
DESCRIPTION
•
These beaches are moderate-to-steeply sloping, of variable
width, and have soft sediments. These characteristics
combine to lower their trafficability
•
Generally species density and diversity is lower than on
fine-grained sand beaches
•
They are very common along the coasts of the open sounds,
specifically south western Rhode Island, where they occur as
long, continuous features in front of coastal ponds or
lagoons. They are commonly recreational areas such as
Weekapaug and Quonochontaug beaches
PREDICTED OIL BEHAVIOR
•
•
•
•
•
•
During small spills, oil will be deposited primarily as a band
along the high-tide line
Under very heavy accumulations, oil may spread across the
entire beach face, though the oil will be lifted off the lower
part of the beach with the rising tide
Penetration of oil into coarse-grained sand can reach 25 cm
Burial of oiled layers by clean sand can be as rapid as one
tidal cycle and to depths of 60 cm or more
Burial to depths over one meter is possible if the oil comes
ashore at the start of a depositional period
Biological impacts include temporary declines in infaunal
populations, which can also affect important shorebird
foraging areas
Rhode Island – Page 8
RESPONSE CONSIDERATIONS
• Remove oil primarily from the upper swash lines
• Removal of sediment should be limited to avoid erosion
problems
• Mechanical reworking of the sediment into the surf zone
may be used to release the oil without sediment removal
• Activity in the oiled sand should be limited to prevent
mixing oil deeper into the beach
• Use of heavy equipment for oil/sand removal may result in
the removal of excessive amounts of sand; manual cleanup
may be more effective
MIXED SAND AND GRAVEL BEACHES
ESI = 5
DESCRIPTION
•
Moderately sloping beach composed of a mixture of sand
and gravel (gravel component should comprise between 20
to 80 percent of total sediments)
•
Because of the mixed sediment sizes, there may be zones of
pure sand, pebbles, or cobbles
•
There can be large-scale changes in the sediment distribution
patterns depending upon season, because of the transport of
the sand fraction offshore during storms
•
Because of sediment desiccation and mobility on exposed
beaches, there are low densities of attached animals and
plants
•
The presence of attached algae, mussels, and barnacles
indicates beaches that are relatively sheltered, with the more
stable substrate supporting a richer biota
•
Common throughout the study area from the northern most
reaches of Narragansett Bay to Block Island. They are often
found in association with wave-cut bedrock or till platforms
PREDICTED OIL BEHAVIOR
•
During small spills, oil will be deposited along and above
the high-tide swash
•
Large spills will spread across the entire intertidal area
•
Oil penetration into the beach sediments may be up to 50
cm; however, the sand fraction can be quite mobile, and oil
behavior is much like on a sand beach if the sand fraction
exceeds about 40 percent
GRAVEL BEACHES
•
Burial of oil may be deep at and above the high-tide line,
where oil tends to persist, particularly where beaches are
only intermittently exposed to waves
•
In sheltered pockets on the beach, pavements of asphalted
sediments can form if there is no removal of heavy oil
accumulations, because most of the oil remains on the
surface
•
Once formed, these asphalt pavements can persist for many
years
•
Oil can be stranded in the coarse sediments on the lower
part of the beach, particularly if the oil is weathered or
emulsified
•
Low-pressure flushing can be used to float oil away from the
sediments for recovery by skimmers or sorbents. Highpressure spraying should be avoided because of the
potential for transporting contaminated finer sediments
(sand) to the lower intertidal or subtidal zones
•
Mechanical reworking of oiled sediments from the high-tide
zone to the upper intertidal zone can be effective in areas
regularly exposed to wave activity (as evidenced by storm
berms). However, oiled sediments should not be relocated
below the mid-tide zone
•
In-place tilling may be used to reach deeply buried oil layers
in the middle zone on exposed beaches
•
Heavy and weathered oils are more difficult to remove,
requiring scraping and/or hot-water spraying
•
It may be necessary to remove heavily oiled blocks and
replace them
ESI = 6A
DESCRIPTION
•
Gravel beaches can be very steep, with multiple wave-built
berms forming the upper beach. Gravel beaches have the
lowest trafficability of all beach types and may contain shell
and woody debris
•
Because of the high mobility of sediments on exposed gravel
beaches, there are low densities of animals and plants
•
Gravel beaches are common in the study area, often grading
laterally into mixed sand and gravel beaches or found
landward of wave cut platforms. On Block Island gravel
beaches were associated with both wave-cut till platforms
and gravel tidal flats.
PREDICTED OIL BEHAVIOR
•
Deep penetration of stranded oil is likely on gravel beaches
because of their high permeability
•
Long-term persistence will be controlled by the depth of
routine reworking by the waves
•
Along sheltered portions of the shorelines, chronic sheening
and the formation of asphalt pavements is likely where
accumulations are heavy
RESPONSE CONSIDERATIONS
•
Heavy accumulations of pooled oil should be removed
quickly from the upper beachface
•
All oiled debris should be removed
•
Sediment removal should be limited as much as possible
RIPRAP
ESI = 6B
DESCRIPTION
•
Riprap structures are composed of cobble- to boulder-sized
blocks of granite or limestone
•
Riprap structures are used for shoreline protection and tidalinlet stabilization
•
Attached biota are sparse on exposed riprap
•
They are common in highly developed commercial and
residential waterfront areas such as Newport, Jamestown
Shores, and Wickford Harbor
PREDICTED OIL BEHAVIOR
•
Deep penetration of oil between the blocks is likely
•
Oil adheres readily to the rough surfaces of the blocks
•
Uncleaned oil can cause chronic leaching until the oil
hardens
RESPONSE CONSIDERATIONS
• When the oil is fresh and liquid, high pressure spraying
and/or water flooding may be effective, making sure to
recover all liberated oil
Rhode Island – Page 9
EXPOSED TIDAL FLATS
ESI = 7
DESCRIPTION
•
Exposed tidal flats are broad, flat intertidal areas composed
primarily of sand and minor amounts of gravel (in a few
areas). The tidal flats of Block Island’s outer coast are
composed almost entirely of gravel.
•
The presence of sand and gravel indicates that tidal currents
and waves are strong enough to mobilize the sediments
•
They are usually associated with another shoreline type on
the landward side of the flat, though they can occur as
separate shoals; they are commonly associated with tidal
inlets
•
Biological utilization can be very high, with large numbers
of infauna, heavy use by birds for roosting and foraging, and
use by foraging fish
RESPONSE CONSIDERATIONS
PREDICTED OIL BEHAVIOR
•
Oil does not usually adhere to the surface of exposed tidal
flats, but rather moves across the flat and accumulates at the
high-tide line
•
Deposition of oil on the flat may occur on a falling tide if
concentrations are heavy
•
Oil does not penetrate water-saturated sediments
•
Biological damage may be severe, primarily to infauna,
thereby reducing food sources for birds and other predators
SHELTERED ROCKY SHORES
•
Currents and waves can be very effective in natural removal
of the oil
•
Cleanup is very difficult (and possible only during low
tides)
•
The use of heavy machinery should be restricted to prevent
mixing of oil into the sediments
•
Where the high-tide area is accessible, it may be feasible to
remove heavy oil accumulations and oiled debris
•
Low- to high-pressure spraying at ambient
temperatures is most effective when the oil is fresh
ESI = 8A
DESCRIPTION
•
The substrate is solid and composed of bedrock
•
This shoreline type is sheltered from wave activity and
strong currents
•
Sediments (rock debris, etc.) may accumulate at the base of
this shoreline type
•
The slope of the intertidal zone is generally moderate to
steep (greater than 15°) with little width
•
They are not common in the study area. Largest occurrences
are found on Newport Neck
PREDICTED OIL BEHAVIOR
•
Stranded oil will persist because of low energy setting
RESPONSE CONSIDERATIONS
•
Low-pressure flushing at ambient temperatures is most
effective when the oil is fresh and still liquid
•
Care must be taken during flushing operations to prevent
oily effluents from affecting biologically rich, lower
intertidal levels
SHELTERED, SOLID MAN-MADE STRUCTURES
ESI = 8B
DESCRIPTION
•
These structures are solid man-made structures such as
seawalls, groins, revetments, piers, and port facilities
•
Most of the structures are designed to protect a single lot,
thus their composition, design, and condition are highly
variable
•
Most structures are constructed of concrete, wood, or metal
•
Often there is no exposed beach at low tide, but multiple
habitats are indicated if present
•
Attached animal and plant life can be high
•
They are common in highly developed commercial and
residential waterfront areas such as Providence Harbor and
Point Judith Pond
PREDICTED OIL BEHAVIOR
•
•
Oil will adhere readily to rough surfaces, particularly along
the high-tide line, forming a distinct oil band
The lower intertidal zone usually stays wet (particularly if
algae covered), preventing oil from adhering to the surface
RESPONSE CONSIDERATIONS
•
Cleanup of seawalls is usually conducted for aesthetic
reasons or to prevent leaching of oil
Rhode Island – Page 10
water
SHELTERED RIPRAP
ESI = 8C
DESCRIPTION
•
Riprap structures are composed of cobble- to boulder-sized
blocks of granite or limestone
•
These structures are found inside harbors and bays in highly
developed areas, sheltered from direct exposure to waves
•
Attached animal and plant life can be present
•
They are common in highly developed commercial and
residential waterfront areas such as Providence Harbor and
Point Judith Pond
PREDICTED OIL BEHAVIOR
•
Deep penetration of oil between the boulders is likely
•
Oil adheres readily to the rough surfaces
•
If oil is left uncleaned, it may cause chronic leaching until
the oil hardens
RESPONSE CONSIDERATIONS
•
High-pressure spraying may be required to remove oil for
aesthetic reasons and to prevent leaching of oil from the
structure
•
Cleanup crews should make sure to recover all released oil
SHELTERED TIDAL FLATS
ESI = 9A
DESCRIPTION
•
Sheltered tidal flats are composed primarily of mud with
minor amounts of sand and shell
•
They are present in calm-water habitats, sheltered from
major wave activity, and are frequently backed by marshes
•
The sediments are very soft and cannot support even light
foot traffic in many areas
•
Sheltered tidal flats can be sparsely to heavily covered with
algae and/or seagrasses
•
They can have very heavy wrack deposits along the upper
fringe
•
Large concentrations of shellfish, worms, and snails can be
found on and in the sediments
•
They are heavily utilized by birds for feeding
•
They are less common in the study area than sandier
exposed tidal flats. Sheltered flats are often found protected
by sandier flats of the flood tidal deltas associated with inlets
such as The Breachway at Point Judith. They also occur with
very little width in front of salt marsh vegetation
•
In areas of high suspended sediments, sorption of oil can
result in deposition of contaminated sediments on the flats
•
Biological damage may be severe
RESPONSE CONSIDERATIONS
•
These are high-priority areas necessitating the use of spill
protection devices to limit oil-spill impact; deflection or
sorbent booms and open water skimmers should be used
•
Cleanup of the flat surface is very difficult because of the
soft substrate; many methods may be restricted
•
Low-pressure flushing and deployment of sorbents from
shallow-draft boats may be helpful
•
Low- to high-pressure flushing can be used to remove oil
from tree roots and trunks, if deemed necessary in high-use
areas
PREDICTED OIL BEHAVIOR
•
Oil does not usually adhere to the surface of sheltered tidal
flats, but rather moves across the flat and accumulates at the
high-tide line
•
Deposition of oil on the flat may occur on a falling tide if
concentrations are heavy
•
Oil will not penetrate the water-saturated sediments, but
could penetrate burrows and desiccation cracks or other
crevices in muddy sediments
VEGETATED LOW BANKS
ESI = 9B
DESCRIPTION
• These habitats are either low banks with grasses or low
eroding banks with trees and tree roots exposed to the water
• They are flooded occasionally by high water
• These shorelines are most commonly found in fresh or
brackish water localities. Small concentrations often border
sheltered residential seawalls and riprap
PREDICTED OIL BEHAVIOR
• During low water stages there is little impact, with the oil
coating a narrow band of sediment at the water level
• During high water, the oil will cover and coat the grasses
and base of trees
• May cause loss of the grasses, but the trees should survive
unless oil penetrates and persists in the substrate
RESPONSE CONSIDERATIONS
• Low-pressure flushing of oiled areas is effective in removing
moderate to heavy accumulations of oil from along the
banks
• Sorbent and containment boom should be placed on the
water side of the cleanup operations to contain and collect
oil outflow
Rhode Island – Page 11
SALT- AND BRACKISH-WATER MARSHES
ESI = 10A
DESCRIPTION
•
Intertidal wetlands
vegetation
containing
emergent,
herbaceous
•
Width of the marsh can vary widely, from a narrow fringe to
extensive areas
•
Sediments are composed of organic muds except on the
margins of islands where sand is abundant
•
Exposed areas are located along bays with wide fetches and
along heavily trafficked waterways
•
Sheltered areas are not exposed to significant wave or boat
wake activity
•
Resident flora and fauna are abundant with numerous
species with high utilization by birds, fish, and shellfish
•
They are common in the study area with largest
concentrations near inlets and coves. Also found in front of
freshwater marshes
RESPONSE CONSIDERATIONS
•
Under light oiling, the best practice is natural recovery;
natural removal processes and rates should be evaluated
prior to conducting cleanup
•
Heavy accumulations of pooled oil can be removed by
vacuum, sorbents, or low-pressure flushing
•
Cleanup activities should be carefully supervised to avoid
vegetation damage
•
Any cleanup activity must not mix the oil deeper into the
sediments. Trampling of the roots must be minimized
•
Cutting of oiled vegetation should only be considered when
other resources present are at great risk from leaving the
oiled vegetation in place
PREDICTED OIL BEHAVIOR
•
Oil adheres readily to intertidal vegetation
•
The band of coating will vary widely, depending upon the
water level at the time oil slicks are in the vegetation. There
may be multiple bands
•
Large slicks will persist through multiple tidal cycles and
coat the entire stem from the high-tide line to the base
•
If the vegetation is thick, heavy oil coating will be restricted
to the outer fringe, although lighter oils can penetrate
deeper, to the limit of tidal influence
•
Medium to heavy oils do not readily adhere to or penetrate
the fine sediments, but can pool on the surface or in burrows
•
Light oils can penetrate the top few centimeters of sediment
and deeply into burrows and cracks (up to one meter)
FRESHWATER MARSHES
ESI = 10B
DESCRIPTION
•
These are grassy wetlands
herbaceous vegetation
composed
of
emergent
•
They occur upstream of brackish vegetation in the upper
estuary and along creeks and rivers. Concentrations are also
found in coastal ponds and lagoons.
•
Those along major channels are exposed to strong currents
and boat wakes; inland areas are highly sheltered
•
The substrate is seldom exposed since daily water-level
changes are low; greater changes occur during floods
•
Resident flora and fauna are abundant
PREDICTED OIL BEHAVIOR
•
Oil adheres readily to the vegetation
•
The band of coating will vary widely, depending upon the
water level at the time oil slicks are in the vegetation. There
may be multiple bands
•
If the vegetation is thick, heavy oil coating will be restricted
to the outer fringe, although lighter oils can penetrate deeper
RESPONSE CONSIDERATIONS
•
Under light oiling, the best practice is natural recovery;
natural removal processes and rates should be evaluated
prior to conducting cleanup
•
Heavy accumulations of pooled oil can be removed by
SCRUB-SHRUB WETLANDS
ESI = 10D
DESCRIPTION
• Scrub-shrub wetlands consist of woody vegetation less than
6 meters tall including true shrubs, small trees, and trees and
shrubs that are stunted due to environmental conditions
• The sediments are silty clay mixed with organic debris
• They are seasonally flooded, though there are many low,
permanently flooded areas
• Resident flora and fauna are abundant
• This shoreline type is not common in the study area
PREDICTED OIL BEHAVIOR
• Oil behavior depends on water level
• During high water, most of the oil passes through the forest,
coating the vegetation above the waterline
• Woody vegetation is less sensitive than grasses to oil
• Some oil can be trapped and pooled on the swamp flood
plain as water levels drop
Rhode Island – Page 12
vacuum, sorbents, or low-pressure flushing
•
Cleanup activities should be carefully supervised to avoid
vegetation damage
•
Any cleanup activity must not mix the oil deeper into the
sediments. Trampling of the roots must be minimized
•
Cutting of oiled vegetation should only be considered when
other resources present are at great risk from leaving the
oiled vegetation in place
•
Penetration into the floodplain soils is usually limited
because of high water levels, muddy composition, surface
organic debris, and vegetation cover
• Large amounts of oily debris can remain in the wetland
• During dry periods, terrestrial spills flow downhill and
accumulate in depressions or reach waterbodies
RESPONSE CONSIDERATIONS
• Under light oiling, the best practice is natural recovery
• Heavy accumulations of pooled oil can be removed by
vacuum, sorbents, or low-pressure flushing
• Under stagnant water conditions, herding of oil with water
spray may be needed to push oil to collection areas
• Oily debris can be removed where there is access
• Any cleanup activity must not mix the oil deeper into the
sediments. Trampling of the roots must be minimized
• Woody vegetation should not be cut