The Coastal Boundary layer is a 1:24,000-scale, polygon feature-based layer of the legal mylar-based maps adopted by the Commissioner of the Department of Environmental Protection (DEP) (i.e., maps were adopted on a town by town basis) showing the extent of lands and coastal waters as defined by Connecticut General Statute (C.G.S.) 22a-93(5)) within Connecticut's coastal area (defined by C.G.S. 22a-94(c)). The coastal boundary is a hybrid of the original 1:24,000 version maps prepared by DEP consistent with C.G.S. 22a-94(d) (Coastal Area) and the revised boundary mapping undertaken by twenty-two coastal towns prepared pursuant to C.G.S. 22a-94(f). This layer therefore does not replace the legal maps and may not be used for legal determinations. The Coastal Boundary layer includes a single polygon feature that represents the coastal boundary. No other features are included in this layer. Data is compiled at 1:24,000 scale. Attribute information is comprised of an Av_Legend attribute and a CoastB_Flg attribute to denote the coastal boundary. Other attributes include automatically calculated Shape_Length and Shape_Area fields. This data is not updated. Any regulated activity conducted within the coastal boundary by a municipal agency (i.e., plans of development, zoning regulations, municipal coastal programs and coastal site plan review (i.e., site plans submitted to zoning commission, subdivision or resubdivision plans submitted to planning commission, application for special permit or exception to the zoning or planning commissions or zoning board of appeals, variance submitted to zoning board of appeals and a referral of a municipal project)) must be conducted in a manner consistent with the requirements of the Connecticut Coastal Management Act (CMA; C.G.S. 22a-90 to 22a-113). As the Coastal Boundary is a hybrid of the Coastal Area, all state and federal agency activities must be consistent with the requirements of the CMA. As defined in C.G.S. 22a-94(b) the coastal boundary is a "continuous line delineated on the landward side by the interior contour elevation of the one hundred year frequency coastal flood zone, as defined and determined by the National Flood Insurance Act, as amended (USC 42 Section 4101, P.L. 93-234), or a one thousand foot linear setback measured from the mean high water mark in coastal waters, or a one thousand foot linear setback measured from the inland boundary of tidal wetlands mapped under section 22a-20, whichever is farthest inland; and shall be delineated on the seaward side by the seaward extent of the jurisdiction of the state." The original boundary maps were created in 1979 on stable mylar overlay using the 1:24,000-scale US Geological Survey topographic quadrangle maps (mylar film format). The source for tidal wetland maps were the legal 1:24,000 maps (mylar format) adopted by the Commissioner of DEP and transformed to 1:24,000 mylar-scale maps by the Office of Policy and Management (OPM) using an accurate pantograph. OPM similarly converted FEMA's flood insurance maps (various scales) to a 1:24,000 mylar overlay. The inland extent of coastal waters was plotted on 1:24,000 USGS topographic maps following the procedures and sources described in The Boundary Between Saltwater and Freshwater in Connecticut, December 1978 prepared by the State of Connecticut, Department of Environmental Protection, Coastal Area Management Program. The following twenty-two towns have adopted municipal coastal boundaries: Chester, Clinton, Darien, Deep River, East Haven, Essex, Fairfield, Greenwich, Groton, Guilford, Hamden, Ledyard, Madison, Milford, New Haven, New London, North Haven, Norwalk, Old Lyme, Old Saybrook, Stamford and Waterford. The coastal boundary maps for these towns may be at different scales than the original DEP draft maps and may contain minor adjustments to the boundary as permitted in C.G.S. 22a-94(f).

Connecticut Historic Shoreline Wetlands:

1880s NOS T-Sheet Shoreline Features is a 1:10,000-scale, line feature-based layer that includes information depicting historic shoreline features and wetland boundaries for areas of coastal Connecticut during the 1880s. The layer depicts information found on topographic survey sheets (T-sheets) from the US Coast and Geodetic Survey (USC&GS), a predecessor to the National Ocean Service (NOS). The layer represents conditions at a particular point in time. The layer does not depict current conditions. The layer includes ground condition features such as approximate shoreline, shoreline, wetland shoreline, wetland upland boundaries, wetland interior boundaries, man-made shoreline, jetties/breakwaters/groins, and piers/ramps/docks. Semi-submerged marshes, referred to here as "low marshes," ocurring where it is possible to discern marsh-like features waterward of the shoreline are also included. Off shore and riverine islands and rocks may be included depending on the quality of their depiction on the t-sheet. It does not include any non shoreline-centric elements that may have been depicted on the t-sheets such as buildings, roads, bridges, etc., nor does it include other off-shore features like sandbars, mud flats, tidal flats, etc. Features are line locations that represent the approximate location of shoreline features and wetland boundaries. Shoreline, as depicted on the T-sheets that pre-date 1927, reference an approximation of Mean High Water (MHW). Although MHW is technically determined by averaging the height of the high water line, (HWL) the landward extent of the last high tide over a 19 year lunar cycle, USC&GS topographers appoximated MHW by familarizing themselves with the tidal conditions in a given area and noting the assorted physical characteristics of the beach. (For a more complete description of this and other shoreline indicators, the reader is directed to the following article: "Historical Shoreline Change: Error Analysis and Mapping Accuracy," Crowell, M., Leatherman, S., and Buckley, M. Journal of Coastal Research, Vol 7, No. 3, 1991, pp 839-852.) Attribute information is comprised of codes to identify individual features, encode shoreline feature type information, and cartographically represent (symbolize) shoreline features on a map. These codes were derived in part from the National Oceanic & Atmospheric Administration (NOAA) Coastal Services Center (CSC) Historic Digital Shoreline Capture project and modified by the State of Connecticut Department of Environmental Protection to address the inclusion of wetland areas. This data was compiled at 1:10,000 scale. This data is not updated. Purpose: 1880s NOS T-Sheet Shoreline Features is 1:10,000-scale data. It depicts the location of historic shoreline features and wetland boundaries for all of coastal Connecticut with the exception of the area of New Haven Harbor from the West River in West Haven to the New Haven/East Haven town boundary. The features also extend slightly beyond the Connecticut state lines into Rye, New York and Westerly, Rhode Island. Use this layer to display historic shoreline and wetlands. Since this data may be considered a crucial element in land use planning, determination of boundary extents, performing change studies for erosion and accretion examinations and other types of decision making this layer may also be used for analytic purposes. Use this layer with other 1:10,000-scale map data such as any other NOS T-sheet Shoreline or Wetland layers. Not intended for maps printed at map scales greater or more detailed than 1:10,000 scale (1 inch = 833.33 feet.)

1880s NOS T-Sheet Wetland Polygon Features is a 1:10,000-scale, polygon feature-based layer that includes information depicting historic wetlands for areas of coastal Connecticut during the 1880s. The layer depicts information found on topographic survey sheets (T-sheets) from the US Coast and Geodetic Survey (USC&GS), a predecessor to the National Ocean Service (NOS). The layer represents conditions at a particular point in time. The layer does not depict current conditions. The layer includes ground condition features such as wetland areas, interior wetland uplands, and interior wetand waterbodies. Semi-submerged marshes, referred to here as "low marshes," ocurring where it is possible to discern marsh-like features waterward of the shoreline are also included. Off shore and riverine islands and rocks may be included depending on the quality of their depiction on the t-sheet. It does not include any non wetland-centric elements that may have been depicted on the t-sheets such as buildings, roads, bridges, etc., nor does it include other off-shore features like mud flats, tidal flats, etc. Features are polygon locations that represent the approximate location of wetland areas and internal wetland features such as uplands or waterbodies. Shoreline, as depicted on the T-sheets that pre-date 1927, reference an approximation of Mean High Water (MHW). Although MHW is technically determined by averaging the height of the high water line, (HWL) the landward extent of the last high tide over a 19 year lunar cycle, USC&GS topographers appoximated MHW by familarizing themselves with the tidal conditions in a given area and noting the assorted physical characteristics of the beach. (For a more complete description of this and other shoreline indicators, the reader is directed to the following article: "Historical Shoreline Change: Error Analysis and Mapping Accuracy," Crowell, M., Leatherman, S., and Buckley, M. Journal of Coastal Research, Vol 7, No. 3, 1991, pp 839-852.) Attribute information is comprised of codes to identify individual features, encode wetland feature type information, and cartographically represent (symbolize) wetland features on a map. These codes were derived in part from the National Oceanic & Atmospheric Administration (NOAA) Coastal Services Center (CSC) Historic Digital Shoreline Capture project and modified by the State of Connecticut Department of Environmental Protection to address the inclusion of wetland areas. This data was compiled at 1:10,000 scale. This data is not updated. Purpose: 1880s NOS T-Sheet Wetland Polygon Features is 1:10,000-scale data. It depicts the location of historic wetland features for all of coastal Connecticut with the exception of the area of New Haven Harbor from the West River in West Haven to the New Haven/East haven town boundary. The features also extend slightly beyond the Connecticut state lines into Rye, New York and Westerly, Rhode Island. Use this layer to display historic wetlands. Since this data may be considered a crucial element in land use planning, determination of boundary extents, performing change studies for erosion and accretion examinations and other types of decision making this layer may also be used for analytic purposes. Use this layer with other 1:10,000-scale map data such as any other NOS T-sheet Shoreline or Wetland layers. Not intended for maps printed at map scales greater or more detailed than 1:10,000 scale (1 inch = 833.33 feet.)

Connecticut Historic Shoreline Wetlands: 1880s NOS T-Sheet Shoreline Features is a 1:10,000-scale, line feature-based layer that includes information depicting historic shoreline features and wetland boundaries for areas of coastal Connecticut during the 1880s. The layer depicts information found on topographic survey sheets (T-sheets) from the US Coast and Geodetic Survey (USC&GS), a predecessor to the National Ocean Service (NOS). The layer represents conditions at a particular point in time. The layer does not depict current conditions. The layer includes ground condition features such as approximate shoreline, shoreline, wetland shoreline, wetland upland boundaries, wetland interior boundaries, man-made shoreline, jetties/breakwaters/groins, and piers/ramps/docks. Semi-submerged marshes, referred to here as "low marshes," ocurring where it is possible to discern marsh-like features waterward of the shoreline are also included. Off shore and riverine islands and rocks may be included depending on the quality of their depiction on the t-sheet. It does not include any non shoreline-centric elements that may have been depicted on the t-sheets such as buildings, roads, bridges, etc., nor does it include other off-shore features like sandbars, mud flats, tidal flats, etc. Features are line locations that represent the approximate location of shoreline features and wetland boundaries. Shoreline, as depicted on the T-sheets that pre-date 1927, reference an approximation of Mean High Water (MHW). Although MHW is technically determined by averaging the height of the high water line, (HWL) the landward extent of the last high tide over a 19 year lunar cycle, USC&GS topographers appoximated MHW by familarizing themselves with the tidal conditions in a given area and noting the assorted physical characteristics of the beach. (For a more complete description of this and other shoreline indicators, the reader is directed to the following article: "Historical Shoreline Change: Error Analysis and Mapping Accuracy," Crowell, M., Leatherman, S., and Buckley, M. Journal of Coastal Research, Vol 7, No. 3, 1991, pp 839-852.) Attribute information is comprised of codes to identify individual features, encode shoreline feature type information, and cartographically represent (symbolize) shoreline features on a map. These codes were derived in part from the National Oceanic & Atmospheric Administration (NOAA) Coastal Services Center (CSC) Historic Digital Shoreline Capture project and modified by the State of Connecticut Department of Environmental Protection to address the inclusion of wetland areas. This data was compiled at 1:10,000 scale. This data is not updated. Purpose: 1880s NOS T-Sheet Shoreline Features is 1:10,000-scale data. It depicts the location of historic shoreline features and wetland boundaries for all of coastal Connecticut with the exception of the area of New Haven Harbor from the West River in West Haven to the New Haven/East Haven town boundary. The features also extend slightly beyond the Connecticut state lines into Rye, New York and Westerly, Rhode Island. Use this layer to display historic shoreline and wetlands. Since this data may be considered a crucial element in land use planning, determination of boundary extents, performing change studies for erosion and accretion examinations and other types of decision making this layer may also be used for analytic purposes. Use this layer with other 1:10,000-scale map data such as any other NOS T-sheet Shoreline or Wetland layers. Not intended for maps printed at map scales greater or more detailed than 1:10,000 scale (1 inch = 833.33 feet.) 1880s NOS T-Sheet Wetland Polygon Features is a 1:10,000-scale, polygon feature-based layer that includes information depicting historic wetlands for areas of coastal Connecticut during the 1880s. The layer depicts information found on topographic survey sheets (T-sheets) from the US Coast and Geodetic Survey (USC&GS), a predecessor to

The Coastal Area layer is 1:24,000-scale data. It depicts the location of the Connecticut Coastal Area as defined by Connecticut General Statute C.G.S. 22a-94(a). Use this layer to show the Coastal Area. Use this layer with other 1:24,000-scale map data such as the Coastal Boundary, Town Boundaries, Roads and Trails, Airports, Railroads and other base map data derived from the USGS 7.5 minute topographic quadrangle maps and compiled at a 1:24000 scale. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

This dataset displays the boundary of the State of Connecticut's coastal area.View Dataset on the Gateway

Coastal Area & Boundary Polygon: The Coastal Area layer is a 1:24,000-scale, polygon feature-based layer that includes the land and waters that lie within the Coastal Area as defined by Connecticut General Statute (C.G.S.) 22a-94(a). Activities and actions conducted within the coastal area by Federal and State Agencies (i.e., U.S. Army Corps of Engineers (USACOE), DEP regulatory programs, and state plans and actions) must be consistent with all of the applicable standards and criteria contained in the Connecticut Coastal Management Act (C.G.S. 22a-90 to 22a-113). A subset of the Coastal Area, the Coastal Boundary, represents an area within which activities regulated or conducted by coastal municipalities must be consistent with the Coastal Management Act. As defined in this section of the statutes, the Coastal Area includes the land and water within the area delineated by the following: the westerly, southerly and easterly limits of the state's jurisdiction in Long Island Sound; the towns of Greenwich, Stamford, Darien, Norwalk, Westport, Fairfield, Bridgeport, Stratford, Shelton, Milford, Orange, West Haven, New Haven, Hamden, North Haven, East Haven, Branford, Guilford, Madison, Clinton, Westbrook, Deep River, Chester, Essex, Old Saybrook, Lyme, Old Lyme, East Lyme, Waterford, New London, Montville, Norwich, Preston, Ledyard, Groton and Stonington. This layer includes a single polygon feature defined by the boundaries described above. Attribute information is comprised of an Av_Legend to denote the coastal area. Data is compiled at 1:24,000 scale. This data is not updated. The Coastal Boundary layer is a 1:24,000-scale, polygon feature-based layer of the legal mylar-based maps adopted by the Commissioner of the Department of Environmental Protection (DEP) (i.e., maps were adopted on a town by town basis) showing the extent of lands and coastal waters as defined by Connecticut General Statute (C.G.S.) 22a-93(5)) within Connecticut's coastal area (defined by C.G.S. 22a-94(c)). The coastal boundary is a hybrid of the original 1:24,000 version maps prepared by DEP consistent with C.G.S. 22a-94(d) (Coastal Area) and the revised boundary mapping undertaken by twenty-two coastal towns prepared pursuant to C.G.S. 22a-94(f). This layer therefore does not replace the legal maps and may not be used for legal determinations. The Coastal Boundary layer includes a single polygon feature that represents the coastal boundary. No other features are included in this layer. Data is compiled at 1:24,000 scale. Attribute information is comprised of an Av_Legend attribute and a CoastB_Flg attribute to denote the coastal boundary. Other attributes include automatically calculated Shape_Length and Shape_Area fields. This data is not updated. Any regulated activity conducted within the coastal boundary by a municipal agency (i.e., plans of development, zoning regulations, municipal coastal programs and coastal site plan review (i.e., site plans submitted to zoning commission, subdivision or resubdivision plans submitted to planning commission, application for special permit or exception to the zoning or planning commissions or zoning board of appeals, variance submitted to zoning board of appeals and a referral of a municipal project)) must be conducted in a manner consistent with the requirements of the Connecticut Coastal Management Act (CMA; C.G.S. 22a-90 to 22a-113). As the Coastal Boundary is a hybrid of the Coastal Area, all state and federal agency activities must be consistent with the requirements of the CMA. As defined in C.G.S. 22a-94(b) the coastal boundary is a "continuous line delineated on the landward side by the interior contour elevation of the one hundred year frequency coastal flood zone, as defined and determined by the National Flood Insurance Act, as amended (USC 42 Section 4101, P.L. 93-234), or a one thousand foot linear setback measured from the mean high water mark in coastal waters, or a one thousand foot linear setback

The NOAA Coastal Services Center purchased digital ADS40 imagery and digital elevation models of the Connecticut coastline in 2004. The Coastal Connecticut project area is comprised of approximately 930 square miles. A total of 244 orthos (122 natural color and 122 color infrared) were produced to cover this area. Aerial imagery was collected in panchromatic, Red, Green, Blue and Near Infrared which yielded a natural color and false color infrared version of the completed digital orthophotography. Imagery was collected at an approximate altitude of 15,750 feet above mean terrain. These data are the infrared orthoimagery in Geotiff format with associated browse graphics and metadata. RGB orthoimagery associated with these data are archived at the NODC under accession 0086893.

Coastal Area & Boundary Polygon:

The Coastal Area layer is a 1:24,000-scale, polygon feature-based layer that includes the land and waters that lie within the Coastal Area as defined by Connecticut General Statute (C.G.S.) 22a-94(a). Activities and actions conducted within the coastal area by Federal and State Agencies (i.e., U.S. Army Corps of Engineers (USACOE), DEP regulatory programs, and state plans and actions) must be consistent with all of the applicable standards and criteria contained in the Connecticut Coastal Management Act (C.G.S. 22a-90 to 22a-113). A subset of the Coastal Area, the Coastal Boundary, represents an area within which activities regulated or conducted by coastal municipalities must be consistent with the Coastal Management Act. As defined in this section of the statutes, the Coastal Area includes the land and water within the area delineated by the following: the westerly, southerly and easterly limits of the state's jurisdiction in Long Island Sound; the towns of Greenwich, Stamford, Darien, Norwalk, Westport, Fairfield, Bridgeport, Stratford, Shelton, Milford, Orange, West Haven, New Haven, Hamden, North Haven, East Haven, Branford, Guilford, Madison, Clinton, Westbrook, Deep River, Chester, Essex, Old Saybrook, Lyme, Old Lyme, East Lyme, Waterford, New London, Montville, Norwich, Preston, Ledyard, Groton and Stonington. This layer includes a single polygon feature defined by the boundaries described above. Attribute information is comprised of an Av_Legend to denote the coastal area. Data is compiled at 1:24,000 scale. This data is not updated.

The Coastal Boundary layer is a 1:24,000-scale, polygon feature-based layer of the legal mylar-based maps adopted by the Commissioner of the Department of Environmental Protection (DEP) (i.e., maps were adopted on a town by town basis) showing the extent of lands and coastal waters as defined by Connecticut General Statute (C.G.S.) 22a-93(5)) within Connecticut's coastal area (defined by C.G.S. 22a-94(c)). The coastal boundary is a hybrid of the original 1:24,000 version maps prepared by DEP consistent with C.G.S. 22a-94(d) (Coastal Area) and the revised boundary mapping undertaken by twenty-two coastal towns prepared pursuant to C.G.S. 22a-94(f). This layer therefore does not replace the legal maps and may not be used for legal determinations. The Coastal Boundary layer includes a single polygon feature that represents the coastal boundary. No other features are included in this layer. Data is compiled at 1:24,000 scale. Attribute information is comprised of an Av_Legend attribute and a CoastB_Flg attribute to denote the coastal boundary. Other attributes include automatically calculated Shape_Length and Shape_Area fields. This data is not updated. Any regulated activity conducted within the coastal boundary by a municipal agency (i.e., plans of development, zoning regulations, municipal coastal programs and coastal site plan review (i.e., site plans submitted to zoning commission, subdivision or resubdivision plans submitted to planning commission, application for special permit or exception to the zoning or planning commissions or zoning board of appeals, variance submitted to zoning board of appeals and a referral of a municipal project)) must be conducted in a manner consistent with the requirements of the Connecticut Coastal Management Act (CMA; C.G.S. 22a-90 to 22a-113). As the Coastal Boundary is a hybrid of the Coastal Area, all state and federal agency activities must be consistent with the requirements of the CMA. As defined in C.G.S. 22a-94(b) the coastal boundary is a "continuous line delineated on the landward side by the interior contour elevation of the one hundred year frequency coastal flood zone, as defined and determined by the National Flood Insurance Act, as amended (USC 42 Section 4101, P.L. 93-234), or a one thousand foot linear setback measured from the mean high water mark in coastal waters, or a one thousand foot linear setback

This data consists of a composite inundation hazards layer for counties from TX to ME, which have a flood exposure snapshot. The dataset was developed from a union of FEMA flood hazard, USACE hurricane evacuation study, NOAA sea level rise of 3-ft above MHHW, and NOAA Shallow Coastal flooding georeferenced digital data. The source and date have been preserved for each source dataset in the attribution. A unique identifier for each hazard, a total number of hazards and hazard description list in the attribution provide coastal risk exposure for each polygon

This layer is sourced from maps.coast.noaa.gov.

This map service presents spatial information developed as part of the National Oceanic and Atmospheric Administration (NOAA) Office for Coastal Management’s Coastal Flood Exposure Mapper. The purpose of the online mapping tool is to provide coastal managers, planners, and stakeholders a preliminary look at exposures to coastal flooding hazards. The Mapper is a screening-level tool that uses nationally consistent data sets and analyses. Data and maps provided can be used at several scales to help communities initiate resilience planning efforts. Currently the extent of the Coastal Flood Exposure Mapper covers U.S. coastal areas along the Gulf of Mexico and Atlantic Ocean. NOAA provides the information “as-is” and shall incur no responsibility or liability as to the completeness or accuracy of this information. NOAA assumes no responsibility arising from the use of this information. For additional information, please contact the NOAA Office for Coastal Management (coastal.info@noaa.gov).

© NOAA Office for Coastal Management

description: This data set contains vector polygons representing the boundaries of the U.S. Geological Survey 1:24,000 topographic maps and other map and digital data boundaries used in the creation of the Environmental Sensitivity Index (ESI) for Rhode Island, Connecticut, New York, and New Jersey.This data set comprises a portion of the ESI data for Rhode Island, Connecticut, New York, and New Jersey. ESI data characterize the marine and coastal environments and wildlife by their sensitivity to spilled oil. The ESI data include information for three main components: shoreline habitats, sensitive biological resources, and human-use resources.; abstract: This data set contains vector polygons representing the boundaries of the U.S. Geological Survey 1:24,000 topographic maps and other map and digital data boundaries used in the creation of the Environmental Sensitivity Index (ESI) for Rhode Island, Connecticut, New York, and New Jersey.This data set comprises a portion of the ESI data for Rhode Island, Connecticut, New York, and New Jersey. ESI data characterize the marine and coastal environments and wildlife by their sensitivity to spilled oil. The ESI data include information for three main components: shoreline habitats, sensitive biological resources, and human-use resources.

Salt Water Limit is a 1:24000-scale, line feature-based layer that depicts the approximate salt water limits of watercourses and embayments in coastal Connecticut. It is important to note that the exact demarcation of the salt-water extent is often not accurate. As stated in the report known as Source 1 in this metadata ("The Boundary Between Freshwater and Saltwater in Connecticut"): "Any definition and demarcation of the boundary between saltwater and freshwater is, of necessity, an approximation. The boundary is transitory and, at times, vague. Within a given body of water, it may vary from day to day, season to season, and year to year, according to such predictable and unpredictable factors as tidal magnitude, rate of evaporation, climatological and meteorological factors, estuarine circulation patterns, and the degree of vertical salinity stratification. An exact delimitation of the upstream limits of saltwater would be a difficult task and one that is probably not necessary for the purposes of coastal management in Connecticut. However, since the primary goal of Connecticut's Coastal Area Management Program is to provide for the balanced, coordinated management of coastal resources, the coastal waters of the state must be clearly and uniformly defined as required in federal and state legislation." The source data for this layer (a compilation of reports and maps) varied in cartographic scale and age but features were digitized onto standard 1:24,000 scale US Geological Survey (USGS) topographic quadrangle maps. Because of this, the layer does not represent conditions at any particular point in time, nor does every waterbody have an associated salt water extent. This data layer has been updated in 2005 to include more robust attribute information, but no further updates are planned. Attribute information is comprised of an AV_LEGEND attribute that identifies the feature as the salt water extent ("Salt Limit"), eight "DATASRC[1-8]" attributes that contain a boolean (0,1) value identifying whether or not that particular source was used, a NOTES attribute for additional data source descriptions, a QUADNUMBER attribute and a QUAD_NAME attribute.

The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and the Connecticut Department of Energy and Environmental Protection (CT DEEP), is producing detailed geologic maps of the coastal sea floor. Bathymetry and sidescan-sonar imagery, originally collected by NOAA for charting purposes, provide a fundamental framework for research and management activities in Long Island Sound, shows the composition and terrain of the seabed, and provides information on sediment transport and benthic habitat. During April-May 2009 NOAA completed hydrographic survey H12013 offshore of the entrance to the Connecticut River, and during November 2009 and April 2010 bottom photographs and surficial sediment data were acquired as part of two ground-truth reconnaissance surveys of this area. Two interpretive data layers were derived from the multibeam echo-sounder and the ground-truth data used to verify them. For more information on the ground-truth surveys see: http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2009-059-FA and http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2010-010-FA

The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and the Connecticut Department of Energy and Environmental Protection (CT DEEP), is producing detailed geologic maps of the coastal sea floor. Bathymetry and sidescan-sonar imagery, originally collected by NOAA for charting purposes, provide a fundamental framework for research and management activities in Long Island Sound, shows the composition and terrain of the seabed, and provides information on sediment transport and benthic habitat. During April-May 2009 NOAA completed hydrographic survey H12013 offshore of the entrance to the Connecticut River, and during November 2009 and April 2010 bottom photographs and surficial sediment data were acquired as part of two ground-truth reconnaissance surveys of this area. Two interpretive data layers were derived from the multibeam echo-sounder and the ground-truth data used to verify them. For more information on the ground-truth surveys see: http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2009-059-FA and http://woodshole.er.usgs.gov/operations/ia/public_ds_info.php?fa=2010-010-FA

This data set is the 1994-2006-era classification for Connecticut, a subset of zone 65. This data set utilized 41 full or partial Landsat 5 Thematic Mapper scenes which were analyzed according to the Coastal Change Analysis Program (C-CAP) protocol to determine land cover.

This Coastal Barrier Resources System (CBRS) data set, produced by the U.S. Fish and Wildlife Service (Service), contains areas designated as undeveloped coastal barriers in accordance with the Coastal Barrier Resources Act (CBRA), 16 U.S.C. 3501 et seq., as amended. The boundaries used to create the polygons herein were compiled between 12/6/2013 and 12/16/2016 from the official John H. Chafee Coastal Barrier Resources System CBRS maps. The boundaries of the CBRS Units in Connecticut, Massachusetts, Rhode Island, and the Long Island portion of New York, were digitized from the official paper maps according to the guidelines in a notice published in the Federal Register on August 29, 2013 (see the â Georeferencing and Boundary Interpretationâ and â Boundary Transcriptionâ sections of 78 FR 53467; available at https://www.federalregister.gov/d/2013-21167). In all other cases where the official map was created through digital methods, the digital boundary was used. These digital polygons are only representations of the CBRS boundaries shown on the official CBRS maps and are not to be considered authoritative. The Service is not responsible for any misuse or misinterpretation of this digital data set, including use of the data to determine eligibility for federal financial assistance such as federal flood insurance. CBRS maps are either enacted by Congress or adopted administratively by the Secretary of the Interior (Secretary), and are maintained by the Service. As maps are revised, this data set will be updated with the new boundaries. Copies of the official CBRS maps are available for viewing at Serviceâ s Headquarters office and are also available to view or download at https://www.fws.gov/ecological-services/habitat-conservation/cbra/Maps/index.html. CBRS boundaries viewed using the CBRS Mapper or the shapefile are subject to misrepresentations beyond the Serviceâ s control, including misalignments of the boundaries with third party base layers and misprojections of spatial data. The official CBRS map is the controlling document and should be consulted for all official determinations. Official determinations are recommended for all properties that are in close proximity (within 20 feet) of a CBRS boundary. For an official determination of whether or not an area or specific property is located within the CBRS, please follow the procedures found at https://www.fws.gov/ecological-services/habitat-conservation/cbra/Determinations.html. For any questions regarding the CBRS, please contact your local Service field office or email CBRA@fws.gov. Contact information for Service field offices can be found at http://www.fws.gov/offices.

These data provide a preliminary overview, at a National scale, of the relative susceptibility of the Nation's coast to sea-level rise through the use of a coastal vulnerability index (CVI). This classification is based upon the following variables: geomorphology, regional coastal slope, tide range, wave height, relative sea-level rise and shoreline erosion and accretion rates. The combination of these variables and the association of these variables to each other furnish a broad overview of regions where physical changes are likely to occur due to sea-level rise. The purpose of these data layers is to allow the user to view both the coastal vulnerability index (CVI) and the data from which the CVI is calculated (tides, wave height, relative sea-level rise, coastal slope, geomorphology, and shoreline erosion and accretion rate) for the U.S. Atlantic, Gulf, and Pacific Coasts. The CVI provides insight into the relative potential for coastal change due to future sea-level rise. The maps and data presented here can be viewed in at least two ways: 1) as a base for developing a more complete inventory of variables influencing the coastal vulnerability to future sea-level rise to which other elements can be added as they become available; and 2) as an example of the potential for assessing coastal vulnerability to future sea-level rise using objective criteria.

description: The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and the Connecticut Department of Energy and Environmental Protection (CT DEEP), has produced detailed geologic maps of the coastal sea floor. Bathymetry, originally collected by NOAA for charting purposes, provides a fundamental framework for research and management activities in Long Island Sound, shows the terrain of the seabed, and provides information on sediment transport and benthic habitat. During April 2009 NOAA completed hydrographic survey H12012 offshore in the northeastern Sound, and during April 2010 and May 2010 bottom photographs and surficial sediment data were acquired as part of two ground-truth reconnaissance surveys of this area. Two interpretive data layers were derived from the multibeam echo-sounder and the ground-truth data used to verify them. For more information on the ground-truth surveys see: https://cmgds.marine.usgs.gov/fan_info.php?fan=2010-010-FA and https://cmgds.marine.usgs.gov/fan_info.php?fan=2010-015-FA.; abstract: The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and the Connecticut Department of Energy and Environmental Protection (CT DEEP), has produced detailed geologic maps of the coastal sea floor. Bathymetry, originally collected by NOAA for charting purposes, provides a fundamental framework for research and management activities in Long Island Sound, shows the terrain of the seabed, and provides information on sediment transport and benthic habitat. During April 2009 NOAA completed hydrographic survey H12012 offshore in the northeastern Sound, and during April 2010 and May 2010 bottom photographs and surficial sediment data were acquired as part of two ground-truth reconnaissance surveys of this area. Two interpretive data layers were derived from the multibeam echo-sounder and the ground-truth data used to verify them. For more information on the ground-truth surveys see: https://cmgds.marine.usgs.gov/fan_info.php?fan=2010-010-FA and https://cmgds.marine.usgs.gov/fan_info.php?fan=2010-015-FA.

See full Data Guide here. This data layer includes the information portrayed on the Surficial Materials Map of Connecticut (Stone, J.R., Schafer, J.P., London, E.H. and Thompson, W.B., 1992, U.S. Geological Survey special map, 2 sheets, scale 1:125,000). The Surficial Materials Map of Connecticut portrays the glacial and postglacial deposits of Connecticut in terms of their aerial extent and subsurface textural relationships. Glacial Ice-Laid Deposits (thin till, thick till, end moraine deposits) and Postglacial Deposits (alluvium, swamp deposits, marsh deposits, beach deposits, talus, and artificial fill) are differentiated from Glacial Meltwater Deposits. The meltwater deposits are further characterized using four texturally-based map units (g = gravel, sg = sand and gravel, s = sand, and f = fines). In many places a single map unit (e.g. sand) is sufficient to describe the entire meltwater section. Where more complex stratigraphic relationships exist, "stacked" map units are used to characterize the subsurface (e.g. sg/s/f - sand and gravel overlying sand overlying fines). Where postglacial deposits overlie meltwater deposits, this relationship is also described (e.g. alluvium overlying sand). Map unit definitions (Surficial Materials Polygon Code definitions, found in the metadata) provide a short description of the inferred depositional environment for each of the glacial meltwater map units. This map was compiled at 1:24,000 scale, and published at 1:125,000 scale. Connecticut Surficial Materials is a 1:24,000-scale, polygon and line feature-based layer describing the unconsolidated glacial and postglacial deposits of Connecticut in terms of their grain-size distribution (texture) as compiled at 1:24,000 scale for the Surficial Materials Map of Connecticut. Glacial meltwater deposits (stratified deposits) are particularly emphasized because these sediments are the major groundwater aquifers in the State and are also the major source of construction aggregate. These deposits are described in terms of their subsurface distribution of textures as well as their extent. The texture of meltwater deposits through their total vertical thickness in the subsurface is shown to the extent that it is known or can be inferred. In some places only one textural unit (such as SG - Sand and Gravel) describes the whole vertical extent of the meltwater deposits; in other places 'stacked units' (such as SG/S/F - Sand and Gravel overlying Sand overlying Fines) indicate changes of textural units in the subsurface. Polygon features represent individual textural (surficial material) units with attributes that describe textural unit type and size. Examples of polygon features that are postglacial deposits include floodplain alluvium, swamp deposits, salt-marsh and estuarine deposits, talus, coastal beach and dune deposits, and artificial fill. Examples of glacial ice-laid deposits include till, thin till, thick till and end moraine deposits. Examples of glacial melt-water deposits include gravel, sand and gravel, sand, and very fine sand, silt and clay. Additional polygon features are incorporated to define surface water areas for streams, lakes, ponds, bays, and estuaries greater than 5 acres in size. Line features describe the type of boundary between individual textural units such as a geologic contact line between two different textural units or a linear shoreline feature between a textural unit and an adjacent waterbody. Data is compiled at 1:24,000 scale and is not updated.

This data layer includes the information portrayed on the Surficial Materials Map of Connecticut (Stone, J.R., Schafer, J.P., London, E.H. and Thompson, W.B., 1992, U.S. Geological Survey special map, 2 sheets, scale 1:125,000). The Surficial Materials Map of Connecticut portrays the glacial and postglacial deposits of Connecticut in terms of their aerial extent and subsurface textural relationships. Glacial Ice-Laid Deposits (thin till, thick till, end moraine deposits) and Postglacial Deposits (alluvium, swamp deposits, marsh deposits, beach deposits, talus, and artificial fill) are differentiated from Glacial Meltwater Deposits. The meltwater deposits are further characterized using four texturally-based map units (g = gravel, sg = sand and gravel, s = sand, and f = fines). In many places a single map unit (e.g. sand) is sufficient to describe the entire meltwater section. Where more complex stratigraphic relationships exist, "stacked" map units are used to characterize the subsurface (e.g. sg/s/f - sand and gravel overlying sand overlying fines). Where postglacial deposits overlie meltwater deposits, this relationship is also described (e.g. alluvium overlying sand). Map unit definitions (Surficial Materials Polygon Code definitions, found in the metadata) provide a short description of the inferred depositional environment for each of the glacial meltwater map units. This map was compiled at 1:24,000 scale, and published at 1:125,000 scale. Connecticut Surficial Materials is a 1:24,000-scale, polygon and line feature-based layer describing the unconsolidated glacial and postglacial deposits of Connecticut in terms of their grain-size distribution (texture) as compiled at 1:24,000 scale for the Surficial Materials Map of Connecticut. Glacial meltwater deposits (stratified deposits) are particularly emphasized because these sediments are the major groundwater aquifers in the State and are also the major source of construction aggregate. These deposits are described in terms of their subsurface distribution of textures as well as their extent. The texture of meltwater deposits through their total vertical thickness in the subsurface is shown to the extent that it is known or can be inferred. In some places only one textural unit (such as SG - Sand and Gravel) describes the whole vertical extent of the meltwater deposits; in other places 'stacked units' (such as SG/S/F - Sand and Gravel overlying Sand overlying Fines) indicate changes of textural units in the subsurface. Polygon features represent individual textural (surficial material) units with attributes that describe textural unit type and size. Examples of polygon features that are postglacial deposits include floodplain alluvium, swamp deposits, salt-marsh and estuarine deposits, talus, coastal beach and dune deposits, and artificial fill. Examples of glacial ice-laid deposits include till, thin till, thick till and end moraine deposits. Examples of glacial melt-water deposits include gravel, sand and gravel, sand, and very fine sand, silt and clay. Additional polygon features are incorporated to define surface water areas for streams, lakes, ponds, bays, and estuaries greater than 5 acres in size. Line features describe the type of boundary between individual textural units such as a geologic contact line between two different textural units or a linear shoreline feature between a textural unit and an adjacent waterbody. Data is compiled at 1:24,000 scale and is not updated.

This GIS layer represents the researcher's interpretation of the regional distribution of sea-floor sedimentary environments in Long Island Sound.

Long Island Sound is one of the largest estuaries along the Atlantic coast of the United States. It is a glacially produced, semi-enclosed, northeast-southwest-trending embayment, which is 150 km long and 30 km across at its widest point. Its mean water depth is approximately 24 m. The eastern end of the Sound opens to the Atlantic Ocean through several large passages between islands, whereas the western end is connected to New York Harbor through a narrow tidal strait. Long Island Sound abuts the New York-Connecticut metropolitan area and contains more than 8 million people within its watershed. A study of the modern sedimentary environments on the sea floor within the Long Island Sound estuarine system was undertaken as part of a larger research program by the U.S. Geological Survey (Coastal and Marine Geology Program) conducted in cooperation with the State of Connecticut Department of Environmental Protection and the U.S. Environmental Protection Agency. Knowledge of the bottom sedimentary environments was needed to discern the long-term fate of wastes and contaminants that have been, or potentially will be, introduced into the system and to help understand the distribution of benthic biologic habitats.

The original interpretation was hand-drawn on mylar based on sidescan-sonar data, seismic-reflection profiles, and sediment sample data collected in the study area. The extent of this orginal work only extended shoreward to the 10m contour interval. This interpretation was then digitized on a digitizing table. This line information was then transferred to Arc/Info where significant cleaning of the data was done. These arcs were then converted to polygons and the attribute information attached. Subsequently, data from the 10 m contour shoreward was incorporated into the original mylar interpretive map. These changes were then digitized and incorporated into the existing Arc/Info coverage. Again, significant cleaning of the arcs as well as assigning the attribute information was done in Arc/Info. The original projection of this work was UTM zone 18, NAD27. For this publication, these data were reprojected into UTM zone 18 NAD 83. This Arc coverage was exported in the e00 format and imported into ArcView. The new theme was then saved in the shapefile format.

Eelgrass Beds Historic Set:

Historic Eelgrass Points is a 1:24,000-scale, point feature-based layer that depicts the locations of historic eelgrass beds (Zostera marina) in Long Island Sound, the Connecticut River, the Quinnipiac River and other bays, harbors and waterbodies in Connecticut's coastal area. It also includes several points located along the north shore of Long Island. There are a total of 131 point features, the majority of which are located east of the Connecticut River. Point features in this layer are compiled from two major sources: 1) the polygon feature label points in the Historic Eelgrass Beds polygon layer representing sources with a mapping component; and 2) additional points that were based on historic literature review that had no mapping component. Source information including source description and collection date for each point is described in the layer's table data. Feature locations are inexact. Because of the variety of source maps and methods used for their automation, this coverage should be considered to have limited spatial accuracy and is appropriate for general uses only. Actual data collection ranged from 1873 through 1996. This layer was published in 1997 and is not updated. It does not represent current conditions.

Historic Eelgrass Bed Polygons is a 1:24,000-scale, polygon feature-based layer that depicts the locations of historic eelgrass beds (Zostera marina) in Long Island Sound and the Niantic River, as well as in other bays, harbors and waterbodies in Connecticut's coastal area. It also includes several points located along the north shore of Long Island. There are a total of 52 polygon features, all of which (except the Long Island points), are located within or east of the Niantic River. This layer can be used with Historic Eelgrass Points. This layer does not represent current conditions. Rather, it depicts historic eelgrass bed locations that were observed and defined either cartographically or narratively over the course of many years and from various sources. The dates of each source's data collection are noted in the attribute table. Feature locations are inexact. Because of the variety of source maps and methods used for their automation, this information should be considered to have limited spatial accuracy and is appropriate for general uses only. The data was taken from maps of various scales and projections that were drawn between 1905 and 1996. These maps were reduced to approximately 1:24,000 scale and adjusted for best fit; eelgrass areas were redrafted onto USGS Topographic Quadrangle maps for digitizing. In order to create a single polygon coverage, areas were considered to represent a maximum extent of eelgrass beds. This layer was published in 1997 and is not updated.