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Connecticut Town Polygon

Frequently-asked questions:


What does this data set describe?

Title:
Connecticut Town Polygon

Abstract:
Connecticut Town Polygon includes the polygon features of a layer named Town. Town is a 1:24,000-scale, polygon and line feature-based layer that includes state, county and town (municipal) boundary features depicted on the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps for the State of Connecticut. This layer only includes information for Connecticut. Line features include State, county, and town (municipal) boundaries. Polygon features depict the geographic areas for individual towns (municipalities). A town may be represented by more than one polygon feature. For example, in addition to representing the portion of a town on the mainland, a polygon feature may also define an island along the coast of Long Island Sound. 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. Attribute information is comprised of codes to classify and cartographically symbolize political boundaries by type and identify the geographic areas encompassed by individual towns. Polygon feature attributes include state, county, and town codes and names. Feature length and geographic area are encoded for linear and polygon features, respectively. This layer was originally published in 1994. With the exception of the Middletown-Portand town boundary, the 2005 edition, includes the same features originally published in 1994. The Middletown-Portand was corrected and changed from its location, as depicted on the USGS topographic quadrangle maps, from along the banks of the Connecticut River in Portand to the middle of the Connecticut River south of Wilcox Island to the Pecausett Meadows area in Portland. Some attribute information has been slightly modified and made easier to use.

Supplemental information:
The Town layer only includes town boundaries. It does not include the boundary lines of individual boroughs such as the Borough of Stonington, for example. The boundaries of individual boroughs are included in the layer named Town Master from USGS, which is also published by the State of Connecticut, Department of Environmental Protection. In 2004, the State of Connecticut, Department of Environmental Protection developed automated procedures to maintaining feature topology and attribute integrity for the Town Master from USGS layer and layers derived from the Town Master from USGS layer such as the Town Master layer. Using ArcInfo Workstation 8.3 software and Arc Macro Language (AML) scripting environment, the automated procedures were recorded in an AML file named MAKECOVER.AML for the political boundary category of data published by the State of Connecticut, Department of Environmental Protection. The MAKECOVER.AML maintains the features and feature attribute data for the Town Master from USGS, Town Master, Town, Connecticut, and Connecticut Mainland layers. Use the Town Master layer when mapping town boundaries in Connecticut and nearby portions of Massachusetts, New York and Rhode Island. For additional information related to the original source of data from the U.S. Geological Survey, refer to the Data User Guides and Standards for 1:24,000-Scale Digital Line Graphs and Quadrangle Maps available from the U.S. Geological Survey, National Mapping Program.

  1. How should this data set be cited?

    State of Connecticut, Department of Environmental Protection (data editor and publisher), U.S. Geological Survey, National Mapping Program (data compiler), 19940101, Connecticut Town Polygon: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Other citation details:
    The USGS is the collector of the data (compiler). The State of Connecticut, Department of Environmental Protection is the creator and maintainer of the data layer (editor) and producer (publisher) of this information for use. The 2005 Edition essentially includes the same set of geographic features published in 1994. However, the 2005 Edition differs from information published in 1994 primarily as a result of minor corrections and improvements to feature geometry and feature attribute information. Some feature attribute information (data fields) have been slightly modified and made easier to use. This layer includes information that is relatively static and does not change over time. Data is not updated. Data compiled at 1:24,000 scale.

  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -73.742172
    East: -71.781365
    North: 42.052612
    South: 40.949970

  3. What does it look like?

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/connecticuttownfull.gif (GIF)
    Full view of Connecticut Town polygon and line features

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/connecticuttowndetailview.gif (GIF)
    Detail view of Connecticut Town polygons and lines

  4. Does the data set describe conditions during a particular time period?

    Beginning date: 1969
    Ending date: 1984
    Currentness reference:
    Publication dates of the USGS 7.5 minute topographic quadrangle maps for the State of Connecticut through 1984.

  5. What is the general form of this data set?

    Geospatial data presentation form: vector digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      Indirect spatial reference:
      Connecticut town names and numbers

      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • G-polygon (785)

    2. What coordinate system is used to represent geographic features?

      The map projection used is Lambert Conformal Conic.

      Projection parameters:
      Lambert Conformal Conic
      Standard parallel: 41.200000
      Standard parallel: 41.866667
      Longitude of central meridian: -72.750000
      Latitude of projection origin: 40.833333
      False easting: 999999.999996
      False northing: 499999.999998

      Planar coordinates are encoded using coordinate pair.
      Abscissae (x-coordinates) are specified to the nearest 0.000250.
      Ordinates (y-coordinates) are specified to the nearest 0.000250.
      Planar coordinates are specified in survey feet.

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

      Vertical coordinate system definition:
      Altitude system definition:
      Altitude resolution: 1.000000
      Altitude encoding method: Explicit elevation coordinate included with horizontal coordinates

  7. How does the data set describe geographic features?

    Connecticut Town Polygon
    Polygon features depict the geographic areas for Connecticut towns (municipalities), Connecticut islands in Long Island Sound and the waters of Long Island Sound. A town may be represented by more than one polygon feature. For example, in addition to representing the portion of a town on the mainland, polygons features also define islands along the coast. (Source: State of Connecticut, Department of Environmental Protection and U.S. Geological Survey, National Mapping Program)

    OBJECTID
    Internal feature number. (Source: ESRI)
                      

    Sequential unique whole numbers that are automatically generated.

    SHAPE
    Feature geometry. (Source: ESRI)
                      

    Coordinates defining the features.

    TBPOLY_COD
    Town Boundary Polygon Code - Numeric values that identify town polygon area feature types. Differentiates town polygon features on land verses in open water, in Connecticut and out of state. (Source: State of Connecticut, Department of Environmental Protection)
                      

    ValueDefinition
    100
    Connecticut Town
    101
    Connecticut Waters

    TOWN_POLY
    Town Boundary Polygon Type - Text values that correspond to numeric TBPOLY_COD attribute values. TOWN_POLY is the English language equivalent of (decodes) the TBPOLY_COD field. (Source: State of Connecticut, Department of Environmental Protection)
                      

    See Enumerated Domain Value Definitions for TBPOLY_COD attribute.

    AV_LEGEND
    ArcView Legend. A text field for symbolizing different feature types on a map. (Source: State of Connecticut, Department of Environmental Protection)
                      

    ValueDefinition
    Connecticut Town
    Includes features with TBPOLY_COD attribute value 100.
    Water
    Includes features with TBPOLY_COD attribute value 101.

    IMS_LEGEND
    Internet Mapping Software Legend. A text field for classifying and symbolizing feature types in a simple manner for an Internet map. (Source: State of Connecticut, Department of Environmental Protection)
                      

    ValueDefinition
    Town
    Includes features with TBPOLY_COD attribute value 100.
    Water
    Includes features with TBPOLY_COD attribute value 101.

    COASTP_COD
    Coastal Polygon Code. Identifies polygon features that are landward and seaward of a series of connecting hydrography line features that define a shoreline along the coast. These connecting hydrography line features that define the shoreline along the coast are referred to as Coastline Arcs and have a COASTA_COD value of 2. Coastline Arc features from the Hydrography layer have been incorporated into the Town Master layer to enclose town polygon features along the coast. Coastline Arcs define a cartographic boundary that separates inland (landward) features from coastal (seaward) features. This shoreline boundary does not represent a line of demarcation between tidal and non-tidal waters or between fresh, saline and brackish waters. Rather, these features define a standard shoreline boundary that is often incorporated into other layers compiled at 1:24,000 scale for consistency. (Source: State of Connecticut, Department of Environmental Protection)
                      

    ValueDefinition
    1
    Inland Polygons - Polygon features that represent the mainland. These polygon features are inland (landward) line features that define the Coastline Arcs, which have a COASTA_COD value of 2.
    2
    Coastal Island Polygons - Polygon features that represent islands along the Connecticut coastline. These polygon features are seaward of Coastline Arc line features, which have a COASTA_COD value of 2.
    3
    Coastal Water Polygons - Polygon features that represent the coastal waters of Long Island Sound, Fishers Island Sound and Block Island Sound, including all bays, harbors and coves.  These polygon features are seaward of line features that define the Coastline Arcs, which have a COASTA_COD value of 2. 

    COAST_POLY
    Coastal Polygon - Text values that correspond to numeric COASTP_COD attribute values. COAST_POLY is the English language equivalent of (decodes) the COASTP_COD field. (Source: State of Connecticut, Department of Environmental Protection)
                      

    See Enumerated Domain Value Definitions for COASTP_COD attribute.

    STATE_COD
    State Code - 2 Digit FIPS State Code that identifies the State in which the feature is located. Based on U.S. Department of Commerce, 1987, Codes for the Identification of the States, the District of Columbia and the Outlying Areas of The United States, and Associated Areas (Federal Information Processing Standard 5-2): Washington, DC, National Institute of Standards and Technology. (Source: U.S. Department of Commerce, Bureau of the Census)
                      

    ValueDefinition
    CT
    Connecticut

    FIPS_COD
    FIPS State County Code - The 5-digit FIPS county designation from U.S. Department of Commerce, Bureau of the Census, Geography Division, 1990, Counties and Equivalent Entities of the United States, Its Possessions, and Associated Areas (Federal Information Processing Standard 6-4): Washington, DC, National Institute of Standards and Technology. FIPS PUB 6-4 is available online at http://www.itl.nist.gov/fipspubs/fip6-4.htm (Source: U.S. Department of Commerce, Bureau of the Census)
                      

    ValueDefinition
    09001
    Fairfield
    09003
    Hartford
    09005
    Litchfield
    09007
    Middlesex
    09009
    New Haven
    09011
    New London
    09013
    Tolland
    09015
    Windham

    TOWN_NO
    Town Number - ID number for the Connecticut Town (municipality), based on the Town Codes issued by the State of Connecticut, Office of the State Controller, which range from 1 to 169. These codes are listed at http://www.opm.state.ct.us/pdpd3/data/twn.htm (Source: State of Connecticut, Office of the State Controller)
                      

    ValueDefinition
    0
    Not a Connecticut Town
    1
    Andover
    2
    Ansonia
    3
    Ashford
    4
    Avon
    5
    Barkhamsted
    6
    Beacon Falls
    7
    Berlin
    8
    Bethany
    9
    Bethel
    10
    Bethlehem
    11
    Bloomfield
    12
    Bolton
    13
    Bozrah
    14
    Branford
    15
    Bridgeport
    16
    Bridgewater
    17
    Bristol
    18
    Brookfield
    19
    Brooklyn
    20
    Burlington
    21
    Canaan
    22
    Canterbury
    23
    Canton
    24
    Chaplin
    25
    Cheshire
    26
    Chester
    27
    Clinton
    28
    Colchester
    29
    Colebrook
    30
    Columbia
    31
    Cornwall
    32
    Coventry
    33
    Cromwell
    34
    Danbury
    35
    Darien
    36
    Deep River
    37
    Derby
    38
    Durham
    39
    Eastford
    40
    East Granby
    41
    East Haddam
    42
    East Hampton
    43
    East Hartford
    44
    East Haven
    45
    East Lyme
    46
    Easton
    47
    East Windsor
    48
    Ellington
    49
    Enfield
    50
    Essex
    51
    Fairfield
    52
    Farmington
    53
    Franklin
    54
    Glastonbury
    55
    Goshen
    56
    Granby
    57
    Greenwich
    58
    Griswold
    59
    Groton
    60
    Guilford
    61
    Haddam
    62
    Hamden
    63
    Hampton
    64
    Hartford
    65
    Hartland
    66
    Harwinton
    67
    Hebron
    68
    Kent
    69
    Killingly
    70
    Killingworth
    71
    Lebanon
    72
    Ledyard
    73
    Lisbon
    74
    Litchfield
    75
    Lyme
    76
    Madison
    77
    Manchester
    78
    Mansfield
    79
    Marlborough
    80
    Meriden
    81
    Middlebury
    82
    Middlefield
    83
    Middletown
    84
    Milford
    85
    Monroe
    86
    Montville
    87
    Morris
    88
    Naugatuck
    89
    New Britain
    90
    New Canaan
    91
    New Fairfield
    92
    New Hartford
    93
    New Haven
    94
    Newington
    95
    New London
    96
    New Milford
    97
    Newtown
    98
    Norfolk
    99
    North Branford
    100
    North Canaan
    101
    North Haven
    102
    North Stonington
    103
    Norwalk
    104
    Norwich
    105
    Old Lyme
    106
    Old Saybrook
    107
    Orange
    108
    Oxford
    109
    Plainfield
    110
    Plainville
    111
    Plymouth
    112
    Pomfret
    113
    Portland
    114
    Preston
    115
    Prospect
    116
    Putnam
    117
    Redding
    118
    Ridgefield
    119
    Rocky Hill
    120
    Roxbury
    121
    Salem
    122
    Salisbury
    123
    Scotland
    124
    Seymour
    125
    Sharon
    126
    Shelton
    127
    Sherman
    128
    Simsbury
    129
    Somers
    130
    Southbury
    131
    Southington
    132
    South Windsor
    133
    Sprague
    134
    Stafford
    135
    Stamford
    136
    Sterling
    137
    Stonington
    138
    Stratford
    139
    Suffield
    140
    Thomaston
    141
    Thompson
    142
    Tolland
    143
    Torrington
    144
    Trumbull
    145
    Union
    146
    Vernon
    147
    Voluntown
    148
    Wallingford
    149
    Warren
    150
    Washington
    151
    Waterbury
    152
    Waterford
    153
    Watertown
    154
    Westbrook
    155
    West Hartford
    156
    West Haven
    157
    Weston
    158
    Westport
    159
    Wethersfield
    160
    Willington
    161
    Wilton
    162
    Winchester
    163
    Windham
    164
    Windsor
    165
    Windsor Locks
    166
    Wolcott
    167
    Woodbridge
    168
    Woodbury
    169
    Woodstock

    TOWN
    Town Name - Text values that correspond to numeric TOWN_NO attribute values. TOWN is the English language equivalent of (decodes) the TOWN_NO field. (Source: State of Connecticut, Office of the State Controller)
                      

    See Enumerated Domain Value Definitions for TOWN_NO attribute.

    CNTY_COD
    County Code - Numeric Code for the County established by Office of Policy and Management. These codes are listed at http://www.opm.state.ct.us/pdpd3/data/twn.htm (Source: State of Connecticut, Office of Policy and Management)
                      

    ValueDefinition
    0
    Not a Connecticut County
    1
    Fairfield
    3
    Hartford
    5
    Litchfield
    7
    Middlesex
    9
    New Haven
    11
    New London
    13
    Tolland
    15
    Windham

    COUNTY
    County - Text values that correspond to numeric CNTY_COD attribute values. COUNTY is the English language equivalent of (decodes) the CNTY_COD field. (Source: U.S. Department of Commerce, Bureau of the Census)
                      

    See Enumerated Domain Value Definitions for CNTY_COD attribute.

    ACREAGE
    Calculated area of polygon feature in acres. Note, ACREAGE values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc. (Source: State of Connecticut, Department of Environmental Protection)
                      

    Numeric value

    AREA_SQMI
    Calculated area of polygon feature in square miles. Note, AREA_SQMI values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc. (Source: State of Connecticut, Department of Environmental Protection)
                      

    Numeric value

    SHAPE.area
    SHAPE.len
    Entity and attribute overview:
    Includes polygonal and linear features for political boundary information published on the U.S. Geological Survey 7.5 minute topographic quadrangle maps. Polygon and line features primarily represent town areas and boundaries, respectively, with attributes that distinguish state, county, and town (municipal) areas and boundaries. Information encoded about features includes Town Boundary polygon and arc (line) type classification, standard symbology classification schemes, state, town, county codes, feature area feature area in acreage and square miles, and feature length in miles. Use the AV_LEGEND attribute to symbolize features by type. Use the IMS_LEGEND attribute to more generally symbolize the features by type. Label polygon feature with the TOWN attribute to display town names on a map.

    Entity and attribute detail citation:
    Connecticut Town numbers, based on the Town Codes issued by the State of Connecticut, range from 1 to 169 in the following order:
    
    Andover (1), Ansonia (2), Ashford (3), Avon (4), Barkhamsted (5), Beacon Falls (6), Berlin (7), Bethany (8), Bethel (9), Bethlehem (10), Bloomfield (11), Bolton (12), Bozrah (13), Branford (14), Bridgeport (15), Bridgewater (16), Bristol (17), Brookfield (18), Brooklyn (19), Burlington (20), Canaan (21), Canterbury (22), Canton (23), Chaplin (24), Cheshire (25), Chester (26), Clinton (27), Colchester (28), Colebrook (29), Columbia (30), Cornwall (31), Coventry (32), Cromwell (33), Danbury (34), Darien (35), Deep River (36), Derby (37), Durham (38), Eastford (39), East Granby (40), East Haddam (41), East Hampton (42), East Hartford (43), East Haven (44), East Lyme (45), Easton (46), East Windsor (47), Ellington (48), Enfield (49), Essex (50), Fairfield (51), Farmington (52), Franklin (53), Glastonbury (54), Goshen (55), Granby (56), Greenwich (57), Griswold (58), Groton (59), Guilford (60), Haddam (61), Hamden (62), Hampton (63), Hartford (64), Hartland (65), Harwinton (66), Hebron (67), Kent (68), Killingly (69), Killingworth (70), Lebanon (71), Ledyard (72), Lisbon (73), Litchfield (74), Lyme (75), Madison (76), Manchester (77), Mansfield (78), Marlborough (79), Meriden (80), Middlebury (81), Middlefield (82), Middletown (83), Milford (84), Monroe (85), Montville (86), Morris (87), Naugatuck (88), New Britain (89), New Canaan (90), New Fairfield (91), New Hartford (92), New Haven (93), Newington (94), New London (95), New Milford (96), Newtown (97), Norfolk (98), North Branford (99), North Canaan (100), North Haven (101), North Stonington (102), Norwalk (103), Norwich (104), Old Lyme (105), Old Saybrook (106), Orange (107), Oxford (108), Plainfield (109), Plainville (110), Plymouth (111), Pomfret (112), Portland (113), Preston (114), Prospect (115), Putnam (116), Redding (117), Ridgefield (118), Rocky Hill (119), Roxbury (120), Salem (121), Salisbury (122), Scotland (123), Seymour (124), Sharon (125), Shelton (126), Sherman (127), Simsbury (128), Somers (129), Southbury (130), Southington (131), South Windsor (132), Sprague (133), Stafford (134), Stamford (135), Sterling (136), Stonington (137), Stratford (138), Suffield (139), Thomaston (140), Thompson (141), Tolland (142), Torrington (143), Trumbull (144), Union (145), Vernon (146), Voluntown (147), Wallingford (148), Warren (149), Washington (150), Waterbury (151), Waterford (152), Watertown (153), Westbrook (154), West Hartford (155), West Haven (156), Weston (157), Westport (158), Wethersfield (159), Willington (160), Wilton (161), Winchester (162), Windham (163), Windsor (164), Windsor Locks (165), Wolcott (166), Woodbridge (167), Woodbury (168), and Woodstock (169).
    Entity and attribute detail citation:
    For additional information related to the original source of data from the U.S. Geological Survey, refer to the Data User Guides and Standards for 1:24,000-Scale Digital Line Graphs and Quadrangle Maps available from the U.S. Geological Survey, National Mapping Program.
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Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)


  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    Howie Sternberg
    State of Connecticut, Department of Environmental Protection
    79 Elm Street
    Hartford, Connecticut 06106-5127
    USA

    860-424-3540 (voice)
    860-424-4058 (FAX)
    dep.gisdata@ct.gov
    Hours of Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
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Why was the data set created?

Town is 1:24,000-scale base map data. It depicts the location of all state, county and town (municipal) boundaries published on the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps for the State of Connecticut. For base map purposes, use this layer with other 1:24,000-scale base map data such as Hydrography, Waterbody, Named Waterbody, Roads and Trails, Railroads, and Airports. All of these layers include information for Connecticut. Town may be used as a possible data source for other 1:24,000-scale layers having features that should coincide with the political boundaries on the USGS topographic quadrangle maps. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.)

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How was the data set created?

  1. Where did the data come from?

    Source 1 - Town Master from USGS (source 1 of 4)

    State of Connecticut, Department of Environmental Protection (data editor and publisher), U.S. Geological Survey, National Mapping Program (data compiler), 19940101, Connecticut Town Master from USGS layer: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    Town Master from USGS is a 1:24,000-scale, polygon and line feature-based layer that includes all political boundary features depicted on all of the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps that cover the State of Connecticut. Line features include State, county, town (municipal), and borough boundaries. Polygon features depict the geographic areas for individual towns (municipalities) and cities and boroughs within individual towns. This layer is the primary data source for a set of political boundary layers published by the State of Connecticut, Department of Environmental Protection. The Town Master, Town, Connecticut, and Connecticut Mainland layers are all ultimately derived from the polygon and line features of the Town Master from USGS layer. Note, the town boundary between Middletown and Portand was corrected and changed from its location, as depicted on the USGS topographic quadrangle maps, from along the banks of the Connecticut River in Portand to the middle of the Connecticut River south of Wilcox Island to the Pecausett Meadows area in Portland. Additionally, coastline and island feature information from the Hydrography Master layer was incorporated into the Town Master from USGS layer in order to enclose the land areas encompassed by towns adjacent to Long Island Sound and to define the islands that are part of these coastal towns. Features derived from the Hydrography Master layer are attributed with specific COASTA_COD and COASTP_COD values. Town Master from USGS is in ArcInfo Coverage format.

    Source 2 - Town (source 2 of 4)

    State of Connecticut, Department of Environmental Protection (data editor and publisher), U.S. Geological Survey, National Mapping Program (data compiler), 19940101, Connecticut Town: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    Town is in ArcInfo Coverage format.

    Source 3 - Connecticut_Town_Poly.shp (source 3 of 4)

    State of Connecticut, Department of Environmental Protection (data editor and publisher), U.S. Geological Survey, National Mapping Program (data compiler), 19940101, Connecticut Town Polygon: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut.

    Online links:
    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    A polygon feature-based layer that defines the geographic areas for the State of Connecticut and its counties and towns (municipalities) as depicted on the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps for the State of Connecticut. This layer only includes information for Connecticut. Connecticut_Town_Poly.shp is in Shapefile format.

    Source 4 - Connecticut_Town_Poly (source 4 of 4)

    State of Connecticut, Department of Environmental Protection (data editor and publisher), U.S. Geological Survey, National Mapping Program (data compiler), 19940101, Connecticut Town Polygon: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    A polygon feature-based layer that defines the geographic areas for the State of Connecticut and its counties and towns (municipalities) as depicted on the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps for the State of Connecticut. This layer only includes information for Connecticut. Connecticut_Town_Poly is in Geodatabase Feature Class format.

  2. What changes have been made?

    Date: 2005 (change 1 of 3)
    Create 2005 Edition of Town - The State of Connecticut, Department of Environmental Protection developed an automated procedure to maintain feature topology and attribute integrity for the Town layer by creating (deriving) the layer from a layer named Town Master from USGS. This procedure is documented in an Arc Macro Language (AML) script named MAKECOVER.AML for the political boundary category of data for the State of Connecticut, Department of Environmental Protection. This procedure combined the geometry of certain features and ensured consistent attribute values by programmatically joining lookup data tables to decode numeric code fields and basing certain line attributes on topological relationships between line and polygon features. Topology-based values were obtained for following line attributes: STATE_FLG, FIPS_FLG, CONN_FLG, TOWN_FLG, CITY_FLG, BORO_FLG, CNTY_FLG, TNO_LEFT, TOWN_LEFT, TNO_RIGHT, TOWN_RIGHT, CITY_LEFT, and CITY_RIGHT. For example, given that each line feature inherently has a (from-to) direction, the value for the TNO_LEFT (Town Number Left) line attribute is based the value of the TOWN_NO (Town Number) attribute for the polygon to the left of the boundary line feature. And the TNO_RIGHT (Town Number Right) line attribute is based the value of the TOWN_NO (Town Number) attribute for the polygon to the right of the boundary line feature. The direction of the line feature is arbitrary and usually reflects the direction with which the feature was digitized. Additionally, the MAKECOVER.AML also encoded Boolean type fields that flag (tag) line features such as state boundaries, county boundaries, town boundaries, etc. For example, the CNTY_FLG (Connecticut County Boundary Flag) field stores either a value of "True" or "False" to distinguish county boundaries from other boundaries and is attributed by comparing the value of the CNTY_COD (Connecticut County Code) attribute of the polygon to the left and right of every line feature. If the two CNTY_COD polygon attribute values differ, then the line feature separates towns in two different counties (making it a county boundary) so the CNTY_FLG line attribute is assigned a value of "True". In 2005, all Boolean fields such as STATE_FLG, FIPS_FLG, CONN_FLG, TOWN_FLG, CITY_FLG, and BORO_FLG were converted from storing previously used 1 an 0 numeric values to represent true and false conditions to storing "True" and "False" text string values, respectively. The MAKECOVER.AML creates the Town layer by extracting and processing features from the Town Master from USGS layer. All polygon and line features from the Town Master from USGS layer that defined boundaries in Connecticut were extracted and output to a separate ArcInfo Coverage named TOWN. Subsequently, the CONN_CITY, CONN_BORO polygon attributes and CITY_FLG, BORO_FLG, CITY_LEFT and CITY_RIGHT line attributes were removed and polygon features were dissolved to eliminate smaller city and borough polygon features that were part of (contained within) larger town area polygon features. The MAKECOVER.AML was executed in 2005 in order to derive the Town layer from the 2005 Edition of the Town Master from USGS layer. The name of the resulting ArcInfo coverage created by this automated process is TOWN.
    
    Note, all information is based on boundary lines depicted on USGS topographic quadrangle maps with the exception of most of the state boundary in Long Island Sound. The boundary line between the states of Connecticut and New York is described in Special Laws of Connecticut, Volume 16, pages 1104-1108, Senate Bill #322, An Act Establishing The Boundary Line Between Connecticut and New York. This Special Act documents the latitude and longitude coordinates of the state boundary monuments on the ground and points in the waters of Long Island Sound. These geodetic positions are based on Clark's spheroid of 1866 and are in degrees, minutes and seconds (DMS). The following boundary points enumerated in this act were used to define the state boundary in Long Island Sound.
    
    Point No. 170: Latitude 40 57 03.228, Longitude -73 36 46.418
    Point No. 171: Latitude 41 15 31.321, Longitude -72 05 24.685
    Point No. 172: Latitude 41 17 26.341, Longitude -72 01 10.937
    Point No. 173: Latitude 41 18 37.835, Longitude -71 55 47.626
    Point No. 174: Latitude 41 18 16.249, Longitude -71 54 28.477

    Person responsible for change:
    Howie Sternberg
    State of Connecticut, Department of Environmental Protection
    79 Elm Street
    Hartford, Connecticut 06106
    USA

    860-424-3540 (voice)

    Data sources used in this process:
    • Source 1 - Town Master from USGS

    Data sources produced in this process:
    • Source 2 - Town

    Date: 2005 (change 2 of 3)
    Export to Shapefile format - Converted polygon feature data from an ArcInfo coverage named TOWN to a Shapefile named Town_Connecticut_Poly.shp. Excluded the AREA, PERIMETER, TOWN#, and TOWN-ID attributes from the Shapefile because their values are only maintained by ArcInfo software with spatial data that is ArcInfo coverage format.

    Person responsible for change:
    Howie Sternberg
    State of Connecticut, Department of Environemtal Protection
    79 Elm Street
    Hartford, Connecticut 06106
    USA

    860-424-3540 (voice)

    Data sources used in this process:
    • Source 2 - Town

    Data sources produced in this process:
    • Source 3 - Connecticut_Town_Poly.shp

    Date: 2006 (change 3 of 3)
    Convert to GeoDatabase Feature Class format - Defined new Feature Class named Connecticut_Town_Poly; and imported the attribute definitions, loaded features and imported metadata from Town_Connecticut_Poly.shp shapefile. 
    
    Spatial Reference Properties for Feature Class:
    
    Coordinate System: NAD_1983_StatePlane_Connecticut_FIPS_0600_Feet
    XY Domain MinX: 100000; MaxX: 2247483.645
    XY Domain MinY: 200000; MaxY: 2347483.645
    Precision: 1000

    Person responsible for change:
    Howie Sternberg
    State of Connecticut, Department of Environmental Protection
    Hartford
    Hartford, Connecticut 06106
    USA

    860-424-3540 (voice)

    Data sources used in this process:
    • Source 3 - Connecticut_Town_Poly.shp

    Data sources produced in this process:
    • Source 4 - Connecticut_Town_Poly

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How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

    This data retains the political boundary (linear) feature types identified by the USGS and adds new polygon feature types of importance to the State of Connecticut for the purpose of mapping areas of the State of Connecticut and its counties and towns. All attributes have valid values. Values are within defined domains. The accuracy test for the TBARC_COD and TBPOLY_COD attribute values was conducted by comparing the political boundaries published on the source topographic quadrangle maps with 1:24,000-scale check plots or interactive displays of the data on a computer graphic system. These checkplots and computer displays depicted the features in different colors based on their respective TBARC_COD and TBPOLY_COD values for comparison with the paper quadrangle maps. The TOWN_ARC, TOWN_POLY, AV_LEGEND, and IMS_LEGEND attribute values are based on TBARC_COD and TBPOLY_COD values. TOWN_POLY is the English language equivalent of (decodes) the TBPOLY_COD field for polygon features. TOWN_ARC is the English language equivalent of (decodes) the TBARC_COD field for line features. AV_LEGEND and IMS_LEGEND are broad classifications of TBPOLY_COD and TBARC_COD values for polygon and line features, respectively. Based on the TBPOLY_COD and TBARC_COD attribute values, the TOWN_POLY, TOWN_ARC, AV_LEGEND, and IMS_LEGEND fields were populated through table joins to lookup tables. These decode values were not manually entered. The COASTA_COD line attributes for the shoreline features were transferred with the Coastal Arc (coastline) features copied from the Hydrography Master layer. All other polygon and line features were manually selected and assigned COASTP_COD and COASTA_COD values based on their relative landward and seaward orientation to Coastline Arcs. The COAST_POLY and COAST_ARC attributes decode the COASTP_COD and COASTA_COD attribute values and were populated through table joins to lookup tables. The COAST_POLY field decodes the COASTP_COD field for polygon features. The COAST_ARC field decodes the COASTA_COD field line features. The STATE_COD, FIPS, TOWN_NO, and CNTY_COD polygon attributes were manually entered and visually inspected and compared to information on the USGS 7.5 minute topographic quadrangle maps. The TOWN attribute is the English equivalent of (decodes) the TOWN_NO polygon attribute and was populated though a table join to a town lookup table. The STATE_FLG, FIPS_FLG, CONN_FLG, TOWN_FLG, CNTY_FLG, TNO_LEFT, and TNO_RIGHT line attributes were programmatically attributed, basing line attribute values on polygon and line feature topology relationships. The ACREAGE (area in acres) and AREA_SQMI (area in square miles) fields were automatically calculated for each polygon feature based on computer generated feature area in square feet. The LENGTH_MI (length in miles) field was automatically calculated for each line feature base on computer generated feature length.

  2. How accurate are the geographic locations?

    This data complies with United States National Map Accuracy Standards for 1:24,000 scale maps. According to this standard, not more than 10 percent of the points tested are to be in error by more than 1/50 inch (40 feet) measured on the publication scale of a USGS 7.5 minute topographic quadrangle map.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    The completeness of the data reflects the USGS National Mapping Division standards for feature content of the data sources, which are the Large Scale (7.5 minute) Digital Line Graph (DLG) files available from the USGS. For Connecticut, the Large Scale DLG files used to create this layer are for the 1:24,000-scale topographic quadrangle maps published between 1969 and 1984.  The data is complete in the sense that it accurately reflects the contents of the most recently published USGS topographic quadrangle maps available at the time the State of Connecticut, Department of Environmental Protection began creating the layer. More recent quadrangle maps have been published by the USGS since 1984; however, the State of Connecticut did not incorporate this information into the layer. This data is not updated.

  5. How consistent are the relationships among the observations, including topology?

    Polygon features conform to the following topological rules. Polygons are single part. There are no duplicate polygons. Polygons do not self overlap. Polygons do not overlap other polygons. Polygons are bound by lines. Line features conform to the following topological rules. Lines are single part. There are no duplicate lines. Lines do not self overlap. Lines do not overlap other lines. Lines intersect only at nodes, and nodes anchor the ends of all lines. Lines do not overshoot or undershoot other lines they are supposed to meet and intersect. The tests of logical consistency were performed by the State of Connecticut using ESRI ArcInfo software to maintain feature topology in ArcInfo coverage format. The data is topologically clean. The ArcInfo Clean function was repeatedly used following edits to verify topology and enforce a minimum distance between vertices of 4 feet (fuzzy tolerance) and a minimum allowed overshoot length of 10 feet (dangle length).

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How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access constraints: None. The data is in the public domain and may be redistributed.
Use constraints:
No restrictions or legal prerequisites for using the data. The data is suitable for use at appropriate scale, and is not intended for maps printed at scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet). Although this data set has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the State of Connecticut, Department of Environmental Protection and the U.S. Geological Survey, National Mapping Program as the source for this information. For example, include the following data source description when printing this layer on a map: Political Boundaries - From the Town layer, compiled and published by CT DEP and USGS. Source map scale is 1:24,000.

Distributor 1 of 1

  1. Who distributes the data set?

    State of Connecticut, Department of Enviromental Protection
    79 Elm Street
    Hartford, Connecticut 06106-5127
    USA

    860-424-3540 (voice)
    860-424-4058 (FAX)
    dep.gisdata@ct.gov
    Hours of Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time

  2. What's the catalog number I need to order this data set?

    Connecticut Town Polygon

  3. What legal disclaimers am I supposed to read?

    Although this data set  has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials.  The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata.

  4. How can I download or order the data?

    • Availability in digital form:


    • Data format:
      in format Shapefile, Feature Class, ArcInfo Coverage (version ArcGIS)
      Network links:http://www.ct.gov/deep

    • Cost to order the data: An online copy of the data may be accessed without charge.


  5. Is there some other way to get the data?

    The data distributor does not provide custom GIS analysis or mapping services. Data is available in a standard format and may be converted to other formats, projections, coordinate systems, or selected for specific geographic regions by the party receiving the data.

  6. What hardware or software do I need in order to use the data set?

    Geographic information sytem (GIS), computer-aided drawing or other mapping software is necessary to display, view and access the information.

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Who wrote the metadata?

Dates:
Last modified: 20111209

Metadata author:
Howie Sternberg
State of Connecticut, Department of Environmental Protection
79 Elm Street
Hartford, Connecticut 06106-5127
USA

860-424-3540 (voice)
860-424-4058 (FAX)
dep.gisdata@ct.gov
Hours of Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata(FGDC-STD-001-1998)

Metadata extensions used:
  • http://www.esri.com/metadata/esriprof80.html

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