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Connecticut Sewer Service Area

Frequently-asked questions:


What does this data set describe?

Title:
Connecticut Sewer Service Area

Abstract:
Connecticut Sewer Service Area is 1:24,000-scale, polygon feature-based data that depict sanitary waste water sewer service areas in Connecticut. Most if not all homes and businesses located within a sewer service area discharge sanitary waste water into the local sewer system. Service areas are delineated along streets and around structures and built-up areas shown on the USGS topographic quadrangle maps and orthophotos where sewer pipes were present on the more detailed sewer system maps. The sewer service area boundaries are approximate and may not encompass all areas and establishments currently discharging into the local sewer system. Depicts the areal extent of wastewater sewer systems in existence at the time DEP last updated this information.  Data is compiled at a map scale of 1:24,000 (1 inch =2,000 ft). Attribute information includes a code that distinguishes between existing and proposed areas of sewer service. 

Information was last updated in 1998, with a minor update to New London and Waterford sewer service areas in May, 2006.

Supplemental information:
This information was initially compiled in 1987 by the Natural Resources Center, Connecticut Department of Environmental Protection. Sewer service areas were mapped at 1:24,000-scale on 7½ Minute U.S. Geological Survey topographic quadrangle maps and later digitized.  In 1997 and 1998, the Bureau of Water Management, Department of Environmental Protections updated the digital sewer service area data and included some proposed sewer service areas. A minor update to New London and Waterford sewer service areas was performed in May, 2006.

  1. How should this data set be cited?

    State of Connecticut, Department of Environmental Protection (data compiler, editor and publisher), 19980101, Connecticut Sewer Service Area: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Other citation details:
    The State of Connecticut, Department of Environmental Protection is the collector of the data (compiler), the creator and maintainer of the data layer (editor), and producer (publisher) of this information for use. Data compiled at 1:24,000 scale. Includes information that is dynamic and changes over time.

  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -73.689634
    East: -71.811862
    North: 42.039403
    South: 40.991904

  3. What does it look like?

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/sewerserviceareafullview.gif (GIF)
    Full view of Connecticut Sewer Service Area

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/sewerserviceareadetailview.gif (GIF)
    Detail view Connecticut Sewer Service Area

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

    Calendar date: 19980101
    Currentness reference:
    publication date

  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:
      None

      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • G-polygon (433)

    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?

    Sewer Service Area
    Connecticut Sewer Service Areas represented as polygon features. (Source: State of Connecticut, Department of Environmental Protection)

    OBJECTID
    Internal feature number. (Source: ESRI)
                      

    Sequential unique whole numbers that are automatically generated.

    AV_LEGEND
    ArcView Legend - A text field that differentiates existing and proposed sewer service areas. Use this field to symbololize the Sewer Service area polygon features on a map. (Source: State of Connecticut, Department of Environmental Protection)
                      

    ValueDefinition
    Service
    Areas were sewer service is provided.
    Proposed
    Areas were sewer service is proposed.

    SHAPE
    Feature geometry. (Source: ESRI)
                      

    Coordinates defining the features.

    SHAPE.area
    SHAPE.len
    Entity and attribute overview:
    Features are polygon locations that represent the approximate location of areas served by sewer systems. Includes an attribute, AV_LEGEND, used to differentiate existing and proposed sewer service areas. Use this field to symbololize the Sewer Service area polygon features on a map.

    Entity and attribute detail citation:
    not applicable
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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?

    Dennis Greci
    State of Connecticut, Department of Environmental Protection
    79 Elm Street
    Hartford, Connecticut 06106-5127
    USA

    860-424-3751 (voice)
    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?

Connecticut Sewer Service Area is 1:24,000-scale data that locates areas where sewer service is provided or proposed for construction at the time DEP last updated this information. Use this information for planning purposes only. 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 - Sewer System Maps (source 1 of 4)

    Connecticut Municipalities and regional sewer authorities, Unknown, Municipal Sewer System Maps: Connecticut Municipalities and regional sewer authorities, .

    Type of source media: paper
    Source scale denominator: varies
    Source contribution:
    Includes various sewer system infrastructure maps maintained by municpal governments and sewer authorities that show the locations of sewer pipes, connections, mains, pumps, treatment facilities, etc. These maps are published at various map scales and publication dates.

    Source 2 - compliation sheets (source 2 of 4)

    State of Connecticut, Department of Environmental Protection (data compiler), Unpublished Material, sewer service area compliation sheets: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA .

    Type of source media: Mylar
    Source scale denominator: 24000
    Source contribution:
    Sewer Service Areas compiled by CT DEP on 1:24,000-scale 7.5 minute USGS quadrangle area Mylar overlays.

    Source 3 - Connecticut Sewer Service Area (initial coverage) (source 3 of 4)

    State of Connecticut, Department of Environmental Protection (data compiler, editor and publisher), 19870101, Connecticut Sewer Service Area: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA .

    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    This original version of the Connecticut Sewer Service Area data is in ArcInfo Coverage format with polygon feature topology. The name of the original coverage is SEWERSRV.

    Source 4 - Connecticut Sewer Service Area (source 4 of 4)

    State of Connecticut, Department of Environmental Protection (data compiler, editor and publisher), 19980101, Connecticut Sewer Service Area: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut.

    Online links:
    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    The Connecticut Sewer Service Area in ArcInfo Coverage format was converted to ESRI Shapefile and then to GeoDatabase polygon feature format and named SEWER_SERVICE_AREA.

  2. What changes have been made?

    Date: 19870101 (change 1 of 3)
    Create 1:24,000-scale Sewer Service Area Mylars - The original Sewer Service Area data in ArcInfo Coverage format was based on information mapped and subsequently digitized from a series of 1:24,000-scale Mylar overlays maintained by the State of Connecticut, Department of Environmental Protection (DEP). The following briefly describes a mapping effort to delineate service area boundaries statewide. Mylar overlays for each 1:24,000-scale, 7.5 minute topographic quadrangle map were made by placing a blank sheet of 2 millimeter Mylar on each topographic quadrangle map and manually drafting the neat lines (boundaries) of the topographic quadrangle map on the Mylar. The neat lines were drafted in India ink and are the basis for manually registering (lining up) the overlay to the corresponding topographic quadrangle map. At the time, these overlays were not prepared with the intent of creating a manuscript appropriate for digitizing. Rather, they were meant to be used with and the basis for manually delineating other 1:50,000 and 1:125,000 small-scale Mylar overlays for regional and statewide assessments of areas in Connecticut where sewer service is provided. Due to their 2-millimeter thickness, these Mylars are susceptible to expansion and contraction under varying humidity conditions. They are not a stable base. Also, the neat lines drawn on the overlays registered each overlay to the paper topographic quadrangle map and not a stable-base Mylar of the topographic quadrangle map. Stable-base Mylar is the preferred media when tablet digitizing.
    
    Maps of individual sewer systems across Connecticut were obtained from municipalities and regional sewer authorities. These maps often included the locations of sewer pipes, connections, mains, pumps, treatment facilities, etc. They were published at various map scales and publication dates. CT DEP staff interpretted information on these maps and manually delineated sewer service boundaries on the corresponding quadrangle scale Mylar overlays. Service areas were delineated along streets and around structures and built-up areas shown on the USGS topographic quadrangle map where sewer pipes were present on the more detailed sewer system maps provided by the municipalities. The names of the sewer systems and locations of sewage treatment plants were also mapped on these Mylar overlays.

    Person responsible for change:
    Doug Bigham
    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 - Sewer System Maps

    Data sources produced in this process:
    • Source 2 - compliation sheets

    Date: 19880101 (change 2 of 3)
    Create 1:24,000-scale Connecticut Sewer Service Area (initial coverage) - feature digitizing and attribution (digitizing tablet) method. Using ESRI ArcInfo software, sewer service polygon features were digitized by registering the source map to the digitizing tablet and using the crosshairs of the digitizer's mouse to manually capture the geometry (location) of features drafted on the map. The corners of the USGS 7.5 minute topographic quadrangle maps used as registration points and are depicted on the compilation sheets (Mylar overlays). Each compilation sheet was registered to the digitizing tablet by digitizing (entering) the locations of four quadrangle corner registration points shown on the map. ArcInfo software compared the values of the digitized coordinates with the actual (true) values for the quadrangle corner (tic) features. The Root Mean Square (RMS) error generated by the ArcInfo software indicated the amount of error involved in transforming coordinates from the registered map to the digital layer. RMS errors higher than 0.004 were not acceptable and required re-registering the source map by digitizing the tic locations again. With a correct registration, individual features were manually digitized off the source map and assigned values to distinguish (polygon) areas were sewer service is and is not provided. Where necessary, additional minor corrections (edits) to feature geometry were manually digitized on the screen (heads-up digitizing) at display scales greater than 1:24,000. Feature location and attribute accuracy was visually checked and inspected by symbolizing and labeling features according to attribute value on the computer screen and on hard copy paper maps, and comparing this information to the original information that were digitized. These check plot maps were printed at the same scale as the compilation sheets in order to visually inspect digitizing quality. The ends of service areas along quadrangle boundaries were drawn to line up with the corresponding sewer service boundaries on adjacent quadrangles. Sewer service boundary lines were first digitized as line features, creating an ArcInfo coverage for each USGS topographic quadrangle map area. Line features on adjacent quadrangle ArcInfo coverages were edgematched so that they would snap together and form enclosed polygon features when all quadrangle coverages were appended.  Using the ArcInfo Append command, the line feature based quadrangle coverages were appended to form a statewide coverage. Polygon feature topology was then created using the ArcInfo build command, and the resulting polygon features were manually attributed to identify sewer service polygon features verses those polgyon areas that are not sewered.

    Person responsible for change:
    Doug Bigham, 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 2 - compliation sheets

    Data sources produced in this process:
    • Source 3 - Connecticut Sewer Service Area (initial coverage)

    Date: 19980101 (change 3 of 3)
    Update the 1:24,000-scale Connecticut Sewer Service Area - feature digitizing and attribution (heads up digitizing) method. Using ESRI ArcGIS software, features appearing on the more up to date sewer system maps from varous municipalities were manually digitized on the screen (heads-up digitizing) at display scales greater than 1:24,000 using either USGS 7.5 minute topographic quadrangle maps, orthophotography, or a street network displayed in the background for reference. In some instances, section of the street network were buffered to create new sewer service area polygon features. Sewer service area boundary and attribute accuracy was visually checked and inspected by symbolizing and labeling features according to attribute value on the computer screen and comparing this with information on the original sewer system map.
    
    Starting in 1998, these procedures are followed to update the sewer service area information, as needed. Information is irregularly updated.
    
    Minor update was made to New London and Waterford sewer service areas in May, 2006.

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

    860-414-3540 (voice)
    850-424-4058 (FAX)

    Data sources used in this process:
    • Source 3 - Connecticut Sewer Service Area (initial coverage)

    Data sources produced in this process:
    • Source 4 - Connecticut Sewer Service Area

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

  1. How well have the observations been checked?

    The Connecticut Sewer Service Areas data outlines the street network, residential, commercial and industrially developed areas where most homes and businesses are presumed to discharge sanitary wastewater to the local sewer system. CT DEP delineated these areas by interpreting sewer system maps available from municpal governments and sewer authorities operating sanitary wastewater treatment plants. All attributes have valid values. Values are within defined domains. The accuracy test for the AV_LEGEND attribute values was conducted by visually comparing the original information published on the more detailed sewer system maps with 1:24,000-scale check plots and interactive computer displays of the areas delineated as sewer service areas by CT DEP.

  2. How accurate are the geographic locations?

    The horizontal positional accuracy of this data is unknown.

  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 feature content of the data sources available at the time of compilation and update by DEP. These data sources include sewer system maps largely provided by municaplities operating sanitary wastewater treatment plants that are on file at DEP.

  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. Establishment of logical consistency was performed by the State of Connecticut, Department of Environmental Protection using ESRI ArcGIS software to manually create and control feature topology in Shapefile and later in GeoDatabase feature format. No automated procedures or tests were performed to guarantee desired topology other than visual inspection.

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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. No restrictions or legal prerequisites for accessing the data. The data is in the public domain and may be redistributed.
Use constraints:
None. No restrictions or legal prerequisites for using the data after access is granted. 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 as the source for this information. For example, include the following data source description when printing this layer on a map: Sewer Service - From the Connecticut Sewer Service Area layer, compiled and published by CT DEP. 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 Sewer Service Area

  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 (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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