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Frequently-asked questions:

What does this data set describe?


The stormwater impaired waters layer is based on the 2016 Connecticut Integrated Water Quality Report (IWQR). All waters (rivers, lakes, estuaries) that were listed as impaired (EPA Category 5) in Table 3-4 of the report and all waters that were listed as having an adopted TMDL in place in Table 3-5 were identified. Both lists were then compared to the Impaired Waters guidance in Appendix D of the 2017 General Permit for the Discharge of Stormwater from Small Municipal Separate Storm Sewer Systems Reissuance with Modifications.Waters with adopted TMDLs in the 2016 IWQR for the pollutants of concern listed in Appendix D (phosphorus, nitrogen, bacteria, mercury) of the General Permit were then identified and added to the Stormwater Impaired Waters layer.Waters without a TMDL in the 2016 IWQR were evaluated for causes that matched the causes listed in Appendix D for each pollutant. In addition, any water without a TMDL that mentioned stormwater as a potential cause was identified. These waters were then added to the Stormwater Impaired Waters layer. Waters in Table 3-4 of the IWQR that indicated any of the causes listed for Phosphorus or Nitrogen were listed as impaired for Phosphorus and Nitrogen per DEEP decision.The resulting list of stormwater impaired waterbodies were then matched up with the Connecticut 303(d) Impaired Waters 2016 (rivers, lakes and esturaries) waterbody features using the waterbody id. Information including stormwater pollutant of concern, cause, impaired designated use and TMDL can be identified by clicking on the layer(s) in the MS4 viewer or with the identify tool in a desktop application.Connecticut 303(d) Impaired Waters 2010 is a subset of Connecticut 305(b) Assessed Waters 2010. If one of the designated uses is categorized as not Fully Supporting the assessed waterbody is considered impaired. Additional information about Integrated Water Quality reporting is available at the CT DEEP website.

  1. How should this data set be cited?


  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -73.677570
    East: -71.783287
    North: 42.048842
    South: 41.018290

  3. What does it look like?

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

  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?

      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • String (323)

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

      The map projection used is NAD 1983 StatePlane Connecticut FIPS 0600 Feet.

      Projection parameters:
      NAD 1983 StatePlane Connecticut FIPS 0600 Feet
      Standard parallel: 41.2
      Standard parallel: 41.86666666666667
      Longitude of central meridian: -72.75
      Latitude of projection origin: 40.83333333333334
      False easting: 999999.999996
      False northing: 499999.999998

      Planar coordinates are encoded using coordinate pair.
      Abscissae (x-coordinates) are specified to the nearest 0.000000026813284925708565.
      Ordinates (y-coordinates) are specified to the nearest 0.000000026813284925708565.
      Planar coordinates are specified in foot_us.

      The horizontal datum used is D North American 1983.
      The ellipsoid used is GRS 1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.257222101.

  7. How does the data set describe geographic features?

    Internal feature number. (Source: Esri)

    Sequential unique whole numbers that are automatically generated.

    Feature geometry. (Source: Esri)

    Coordinates defining the features.

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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?

    Connecticut Department of Energy and Environmental Protection (CT DEEP)
    University of Connecticut, Center for Land Use Education and Research (CLEAR)

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

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Why was the data set created?

CT 2016 Impaired Rivers is 1:24,000-scale data. It depicts stormwater impaired waters layer is based on the 2016 Connecticut Integrated Water Quality Report (IWQR).  This layer should be used with the other assessed waterbody layers: Stormwater Impaired Estuary and Stormwater Impaired Lakes. This layer should only be viewed with other 1:24,000-scale map data such as water quality classifications, roads, towns, topographic quadrangles, and digital orthophotos. 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?

  2. What changes have been made?

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

  1. How well have the observations been checked?

  2. How accurate are the geographic locations?

  3. How accurate are the heights or depths?

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

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

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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
Use constraints:

Distributor 0 of 0

  1. Who distributes the data set?

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

  3. What legal disclaimers am I supposed to read?

  4. How can I download or order the data?

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

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

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Who wrote the metadata?

Last modified: 20180627

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

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