FGDC Classic | FGDC FAQ | FGDC Plus | XML

Channels, Basins and Anchorages

Frequently-asked questions:


What does this data set describe?

Title:
Channels, Basins and Anchorages

Abstract:
Channels, Basins, and Anchorages is a 1:20,000-scale, polygon feature-based layer that includes the location of channels, turning basins, and anchorages within (mostly) Connecticut waters. The layer is derived from information depicted on the 2002 edition of digital National Oceanic & Atmospheric Administration (NOAA) nautical charts, Maptech, Inc. and US Army Corps of Engineers (USACOE) Volume 3 - Rivers & Harbors of Rhode Island and Connecticut Project Maps publication dated Sept 1988.  The Channels, Basins, and Anchorages layer was compiled during the summer of 2001. The layer represents conditions at a particular point in time. The layer includes representations of areas of channels, turning basins, and anchorages that are or may be periodically maintained by various entitites for commercial and recreational uses. It does not include all possible/potential such areas, just those identified on the source documents; nor does the layer include any buoys or channel markers designating the bounds or entrances to channels, basins, or anchorages.  Features are polygon locations that represent the approximate or assumed location of channels, turning basins, and anchorages.  Attribute information is comprised of codes to uniquely identify individual features, encode feature information, and cartographically represent (symbolize) channels, turning basins, and anchorages features on a map.  Data is compiled at 1:20,000 scale. This data is not updated.

Supplemental information:
For additional information, refer to the websites of the National Oceanic & Atmospheric Administration (NOAA) at http://www.noaa.gov, or Maptech, Inc. at http://www.maptech.com.

  1. How should this data set be cited?

    State of Connecticut, Department of Environmental Protection (data compiler, editor and publisher), 2002, Channels, Basins and Anchorages: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Other citation details:
    The 2005 Edition of Channels, Basins, and Anchorages essentially includes the same set of geographic features published in 2002. However, the 2005 Edition differs from information published in 2002 primarily as a result of corrections and improvements to feature attribute information. Previously undetected errors have been corrected. Also, some feature attribute information (data fields) have been slightly modified and made easier to use. Except for periodic corrections, this layer includes information that is relatively static and does not change over time.

  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -73.671176
    East: -71.823710
    North: 41.758598
    South: 40.983579

  3. What does it look like?

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/channelsbasinsanchorages.gif (GIF)
    View of Channels, Basins, and Anchorages

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/channelsbasinsanchoragessimpleview.gif (GIF)
    Simple legend view of this layer.

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

    Beginning date: 1991
    Ending date: 2002
    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:
      State of Connecticut, United States of America

      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • G-polygon (140)

    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?

    Channels, Basins and Anchorages
    Channels, Basin, and Anchorages 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.

    Shape
    Feature geometry. (Source: ESRI)
                      

    Coordinates defining the features.

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

    ValueDefinition
    Channel
    Dredged channel
    Basin
    Turning basin
    Anchorage
    Anchorage/mooring area

    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 )
                      

    Range of values
    Units:acres

    RIVER_ETC
    Text field providing the name of any river or stream that a feature may exist in. (Source: State of Connecticut, Department of Environmental Protection )
                      

    Names of waterbodies

    HARBOR_ETC
    Text field providing the name of any cove, bay, or harbor that a feature may exist in. (Source: State of Connecticut, Department of Environmental Protection)
                      

    Names of waterbodies

    SOUND_ETC
    Text field providing the name of any sound that a feature may exist in (Source: State of Connecticut, Department of Environmental Protection )
                      

    Names of waterbodies

    NAME
    Text field providing, where available, the common name of a feature  (Source: State of Connecticut, Department of Environmental Protection )
                      

    General names of channel, basin, or anchorage features

    DATASOURCE
    Text field identifying the data source for the feature (Source: State of Connecticut, Department of Environmental Protection )
                      

    ValueDefinition
    NOAA Nautical Charts
    Feature geometry (shape) derived from 2002 NOAA Digital Nautical Charts
    NOAA Nautical Charts/ACOE Project Maps
    Feature geometry (shape) derived from both 2002 NOAA Digital Nautical Charts and the USACOE Project Maps

    SOURCEINFO
    The name of the data source used to define the feature geometry (e.g., NOAA chart number of USACOE Project map number) (Source: State of Connecticut, Department of Environmental Protection )
                      

    NOAA chart or USACOE map number designations.

    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)
                      

    Range of values
    Units:square miles

    FED_DECODE
    Text field providing an indication of whether or not a feature is federally maintained (Source: State of Connecticut, Department of Environmental Protection )
                      

    Coordinates defining the features.

    ValueDefinition
    Yes
    Feature is federally maintained.
    No
    Feature is not federally maintained.

    SHAPE
    Feature geometry. (Source: ESRI)
                      

    Coordinates defining the features.

    FEDERAL
    Numeric field providing an indication of whether or not a feature is federally maintained (Source: State of Connecticut, Department of Environmental Protection )
                      

    ValueDefinition
    1
    Feature is federally maintained.
    0
    Feature is not federally maintained.

    SHAPE.area
    SHAPE.len
    Entity and attribute overview:
    Includes features such as channels, turning asins, and anchorages. Information encoded about these features includes type, names, and measurement information and standard cartographic symbology classification schemes. Use NAME to uniquely identify features. Use the AV_LEGEND attribute to symbolize features by type on a map. Use the NAME attribute to label features on a map. To define a layer that only includes a certain type of feature, query Channels, Basins, and Anchorages features for AV_LEGEND value equal to either "channel" OR "basin" OR "anchorage" 
Back to Top

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?

    Kevin O'Brien
    State of Connecticut, Department of Environmental Protection
    79 Elm Street
    Hartford, Connecticut 06106-5127
    USA

    860-424-3034 (voice)
    860-424-4054 (FAX)
    dep.gisdata@ct.gov
    Hours of Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
Back to Top

Why was the data set created?

Channels, Basins, and Anchorages is 1:20,000-scale data. It depicts the location of federal and non-federal channels, basins, and anchorages areas. Use this layer to display the locations of underwater boating/shipping areas in and around Long Island Sound and the waterways of Connecticut. Use this layer with 1:20,000-scale map data such as the 2002 digital National Oceanic & Atmospheric Administration (NOAA) Nautical Charts or with any other 1:24,000 scale DEP natural resource data. Not intended for maps printed at map scales greater or more detailed than 1:20,000 scale (1 inch = 1,666.66 feet.)

Back to Top

How was the data set created?

  1. Where did the data come from?

    Source 1 - NOAA Digital Nautical Charts (source 1 of 3)

    National Oceanic & Atmospheric Administration (NOAA), Maptech, Inc. , 2002, NOAA Digital Nautical Chart Kit : State of Connecticut, .

    Online links:
    Type of source media: CD-ROM
    Source scale denominator: 20000
    Source contribution:
    The 2002 National Oceanic & Atmospheric Administration (NOAA) Digital Nautical Charts, once reprojected from their native *.bsb format in decimal degrees into *.tiff files in CT State Plane Corodinates, NAD83, were used as a basemap from which the features of Channels, Basins, and Anchorages were digitzed. 

    Source 2 - USACOE Project Maps (source 2 of 3)

    US Army Corps of Engineers (USACOE) , 1988, US Army Corps of Engineers (USACOE) Volume 3 - Rivers & Harbors of Rhode Island and Connecticut Project Maps.

    Type of source media: paper
    Source scale denominator: varies
    Source contribution:
    Used as a secondary reference to check the location and names of Channels, Basins, and Anchorages.  Also provided information on whether certain areas were Federally maintained or not.

    Souce 3 - Channels, Basins, and Anchorages (source 3 of 3)

    State of Connecticut, Department of Environmental Protection, 2002, Channels, Basins, and Anchorages Layer.

    Type of source media: CD-ROM
    Source scale denominator: 20000
    Source contribution:
    The Channels, Basins, and Anchorages layer is a 1:20,000-scale, polygon feature-based layer that includes the location of channels, basins, and anchorages. Originally published in 2002, this layer is periodically modifed, and different versions have been and may be published over time. Changes made to the entire layer are reflected in the metadata process steps where this source, Source 3 - Channels, Basins, and Anchorage, is cited as both the Source Used and Source Produced. 

  2. What changes have been made?

    Date: 2001 (change 1 of 4)
    Feature digitizing and attribution (heads up digitizing method) - Using ESRI ArcView 3 software, channel, basin, and anchorage features appearing on the National Oceanic & Atmospheric Administration (NOAA) 2002 digital charts were manually digitized on the screen (heads-up digitizing) at display scales greater than 1:20,000. Individual features represent polygon areas designated and noted as either channel, turning basin, or anchorage areas. Features were assigned attribute values based on information shown on the digital charts (i.e, cchannel, turning basin, or anchorage ares.) Feature location and attribute accuracy was visually checked and inspected by symbolizing and labeling features according to attribute value on the computer screen as well as using the USACOE Project Maps as secondary verification.

    Person responsible for change:
    Kevin O'Brien
    State of Connecticut, Department of Environmental Protection

    Data sources used in this process:
    • Source 1 - NOAA Digital Nautical Charts
    • Source 2 - USACOE Project Maps

    Data sources produced in this process:
    • Source 3 - Channels, Basins, and Anchorages

    Date: 2005 (change 2 of 4)
    Attribute enhancements - FED_DECODE attribute was added to decode the values found in  the FEDERAL attribute field.  AREA_SQMI was added to provide the area in square miles.

    Person responsible for change:
    Kevin O'Brien
    State of Connecticut, Department of Environmental Protection

    Data sources used in this process:
    • Souce 3 - Channels, Basins, and Anchorages

    Data sources produced in this process:
    • Souce 3 - Channels, Basins, and Anchorages

    Dataset moved.

    Data sources used in this process:
    • R:\Archive\kevin\final\ChannelsBasinsAnchorages

    Dataset moved.

    Data sources used in this process:
    • R:\Archive\kevin\FIS_data_forStu\Delivery1\ChannelsBasinsAnchorages

Back to Top

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

  1. How well have the observations been checked?

    The Channels, Basins, and Anchorages layer retains the feature types and information identified by the State of Connecticut, Department of Environmental Protection and obtained from the 2002 edition of the digital National Oceanic & Atmospheric Administration (NOAA) Nautical Charts provided by Maptech, Inc., and US Army Corps of Engineers (USACOE) Volume 3 - Rivers & Harbors of Rhode Island and Connecticut Project Maps publication dated Sept 1988.  All attributes have valid values. Values are within defined domains. The accuracy test for the attribute values was conducted by comparing the information presented in the source data with interactive displays of the data on a computer graphic system. These computer displays depicted and labeled the Channels, Basins, and Anchorages features in different colors based on AV_LEGEND and NAME values for comparison with the original data source. AV_LEGEND is a broad classification of Channels, Basins, and Anchorages features. NAME is the name given to a particular feature.  Channels, Basins, and Anchorages features were manually selected and populated with attributes values to identify and describe individual features.

  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, which include the 2002 edition of the digital National Oceanic & Atmospheric Administration (NOAA) Nautical Charts provided by Maptech, Inc. and the US Army Corps of Engineers (USACOE) Volume 3 - Rivers & Harbors of Rhode Island and Connecticut Project Maps publication dated Sept 1988.. The Channels, Basins, and Anchorages layer is complete in the sense that it accurately reflects the contents of the information available at the time the State of Connecticut, Department of Environmental Protection created the layer. However, compared to more recent information available today or current conditions, the Channels, Basins, and Anchorages layer may be incomplete. 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. 
    
    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 format. No automated procedures or tests were performed to guarantee desired topology other than visual inspection.

Back to Top

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 1:20,000 scale (1 inch = 1,666.66 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.

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

    860-424-3034 (voice)
    860-424-4054 (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?

    Channels, Basins and Anchorages

  3. What legal disclaimers am I supposed to read?

  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.

Back to Top

Who wrote the metadata?

Dates:
Last modified: 20120119

Metadata author:
Kevin O'Brien
State of Connecticut, Department of Environmental Protection
79 Elm Street
Hartford, Connecticut 06106-5127
USA

860-424-3034 (voice)
860-424-4054 (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

  • Back to Top