Environmental Justice Block Groups 2022 was created from
Connecticut block group boundary data located in the Census Bureau's 2020
TIGER/Line Shapefiles. The poverty data used to determine which block groups
qualified as EJ communities (see CT State statute 22a-20a) was based on the
Census Bureau's 2020 ACS 5-year estimate. This poverty data was joined with the
block group boundaries in ArcPro. Block groups in which the percent of the
population below 200% of the federal poverty level was greater than or equal to
30.0 were selected and the resulting selection was exported as a new shapefile.
The block groups were then clipped so that only those block groups outside of
distressed municipalities were displayed. Maintenance – This layer will be
updated annually and will coincide with the annual distressed municipalities
update (around August/September). The latest ACS 5-year estimate data should be
used to update this layer. Environmental Justice Distressed Municipalities 2020
was created from Connecticut town boundary data located in the Census Bureau's
2020 TIGER/Line Shapefiles (County Subdivisions). 

See full Data Guide here. Aquifer Protection Areas Set is a 1:24,000-scale, polygon feature-based layer that includes all Preliminary (Level B) and Final (Level A) Aquifer Protection Areas approved by the Connecticut Department of Energy and Environmental Protection (DEEP). These areas represent the land area contributing ground water to active public water supply wells or well fields that serve more than 1000 people that are set in sand and gravel aquifers (stratified drift deposits). These areas are commonly referred to as wellhead protection areas. The Aquifer Protection Areas were delineated by the individual water utilities owning the well fields and submitted to the DEEP for approval. The preliminary mapping provides a general estimate of the area contributing ground water to the well field. The final mapping is based on extensive, site-specific, detailed modeling of the ground water flow system. As the final mapping is completed it replaces the preliminary mapping. The layer is based on information collected and compiled from 1991 to the present. The layer depicts current conditions. Attribute information is comprised of codes to uniquely identify individual features, encode the aquifer protection area type and status, and cartographically represent area features on a map. Data is compiled at 1:24,000 scale. This data is updated as final mapping becomes available.

Connecticut and Vicinity County Boundary data are intended for geographic display of state and county boundaries at statewide and regional levels. Use it to map and label counties on a map. These data are derived from Northeastern United States Political Boundary Master layer.
This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

Connecticut Senate Districts is not intended for maps printed at map scales greater or more detailed than 1:100,000 scale (1 inch = 1.578 mile).

Connecticut State Line includes the line features of a layer named Connecticut. Connecticut is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut. The State of Connecticut is represented as one polygon feature surrounded by linear boundary features. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994.

Connecticut State Polygon includes the polygon features of a layer named Connecticut. Connecticut is a 1:24,000-scale, polygon and line feature-based layer that depicts the geographic area encompassed by and the boundary for the State of Connecticut. The State of Connecticut is represented as one polygon feature surrounded by linear boundary features. The layer is based on information from USGS topographic quadrangle maps published between 1969 and 1984 and latitude and longitude coordinates that define the boundary between the states of Connecticut and New York in Long Island Sound. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994.

Thickness of Glacial Sediment in Connecticut and Long Island Sound Set:
The Thickness of Glacial Sediments in Connecticut and the Long Island Sound Basin layer contains interpretive polygon data representing the thickness of glacial sediments in Connecticut and the Long Island Sound Basin. Compiled as part of the Quaternary Geologic Map of Connecticut and Long Island Sound Basin, Stone and others (1998, 2005). Includes thickness of glacial sediments in 50 foot (0-50, 50-100) and then 100 foot (100-200, 200-300, etc) intervals.
Data derived from original mapping at 1:80,000 scale for the Long Island Sound basin and at 1:125,000 scale on the land in Connecticut. The data are NOT recommended for use at higher resolution scales. The purpose is to show the thickness of glacial sediments on land in Connecticut and in the Long Island Sound Basin. This layer can be used other geologic information shown on the Quaternary Geologic Map of Connecticut and Long Island Sound Basin (USGS publication SIM-2784) as well as other geologic GIS data layers for Long Island Sound derived from the U.S. Geological Survey (USGS) / Connecticut Department of Environmental Protection (DEP) Marine Geology Cooperative Program. Complimentary data layers include the marine transgressive surface (marinet) and thickness of postglacial deposits (pgthkpol) found on Georeferenced Sea-floor Mapping and Bottom Photography in Long Island Sound (USGS Openfile report 00-304).

Surficial Aquifer Texture Map was prepared from 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) to describe unconsolidated areas of the subsurface with similar properties relative to ground water flow. Surficial aquifers are unconsolidated geologic deposits capable of yielding a sufficient quantity of groundwater to wells. Surficial aquifer textures were identified from original surficial materials mapping for use in ground water applications. These are qualitative interpretations of material properties relative to ground water flow. Surficial aquifer texture groups were identified to represent aquifer textures with similar hydraulic conductivities. Some interpretations were made beneath postglacial alluvium and swamp deposits. Alluvium without a subsurface interpretation was classified as having similar hydrologic properties as till. Alluvium areas with subsurface interpretations of fines or coarse grained deposits were classified as having the hydrologic characteristics of the underlying deposits. The aquifer textures include areas of till, fine grained, fine overlying coarse grained, coarse grained, coarse overlying fine grained deposits, artificial fill, beach, salt marsh, swamp, and water. Aquifer texture groups include areas of fine grained , fine overlying coarse grained, coarse grained, and coarse overlying fine grained deposits. Surficial materials not included in the surficial aquifer texture groups include till, artificial fill, beach, salt marsh, swamp, and water. All textural terms follow the grain size classification of Stone et al 1992, modified from Wentworth, 1922. The surficial aquifer texture classifications are suitable for use at 1:24,000 scale.
Original mapping of the Surficial Materials Map of Connecticut is preserved as polygon attribute values in this data layer, and is herein described. 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 o

Northeastern United States Town Boundary data are intended for geographic display of state, county and town (municipal) boundaries at statewide and regional levels. Use it to map and label towns on a map. These data are derived from Northeastern United States Political Boundary Master layer.
This information should be displayed and analyzed at scales appropriate for 1:24,000-scale data. The State of Connecticut, Department of Environmental Protection (CTDEP) assembled this regional data layer using data from other states in order to create a single, seamless representation of political boundaries within the vicinity of Connecticut that could be easily incorporated into mapping applications as background information. More accurate and up-to-date information may be available from individual State government Geographic Information System (GIS) offices. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

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 t

Bedrock Geology Set is a 1:50,000-scale, polygon and line feature-based layer describing the solid material that underlies the soil or other unconsolidated material of the earth for Connecticut. Bedrock geologic formations are described as polygons in terms of formation name (incorporating geologic age), rock type, and tectonic terrane association. Tectonic forces are responsible for the present day geologic configuration of the continents. Resulting terranes are regionally fault bounded rocks of a similar tectonic history. Each terrane is named after its plate tectonics ancestry. Geologic lines include contacts, faults, and terrane boundaries. Terrane boundaries are named for the faults involved. The geologic contacts and faults are delineated and classified by type. Polygon feature attribute information is comprised of codes to identify individual bedrock geologic units, their formation name, description and size. Line feature attributes identify, name and describe bedrock contacts, faults and terrane boundaries between these bedrock geologic units. Data is compiled at 1:50,000 scale and is not updated. A complete description of the bedrock mapping units with mineralogical descriptions and a brief history of Connecticut geology are included in the Supplemental Information Section for reference.

Connecticut Bedrock Geology is a 1:50,000-scale, polygon and line feature-based layer describing the solid material that underlies the soil or other unconsolidated material of the earth for Connecticut. Bedrock geologic formations are described as polygons in terms of formation name (incorporating geologic age), rock type, and tectonic terrane association. Tectonic forces are responsible for the present day geologic configuration of the continents. Resulting terranes are regionally fault bounded rocks of a similar tectonic history. Each terrane is named after its plate tectonics ancestry. Geologic lines include contacts, faults, and terrane boundaries. Terrane boundaries are named for the faults involved. The geologic contacts and faults are delineated and classified by type. Polygon feature attribute information is comprised of codes to identify individual bedrock geologic units, their formation name, description and size. Line feature attributes identify, name and describe bedrock contacts, faults and terrane boundaries between these bedrock geologic units. Data is compiled at 1:50,000 scale and is not updated. A complete description of the bedrock mapping units with mineralogical descriptions and a brief history of Connecticut geology are included in the Supplemental Information Section for reference.