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Connecticut Local Drainage Basins Line

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: State of Connecticut, Department of Environmental Protection (data compiler, editor and publisher)
Publication_Date: 1988
Title:
Connecticut Local Drainage Basins Line
Edition: 2006
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Hartford, Connecticut, USA
Publisher: State of Connecticut, Department of Environmental Protection
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 and digitized from the 1:24,000-scale compilation sheets for the 1:125,000-scale Natural Drainage Basins in Connecticut Map, McElroy, 1981. The 2006 Edition includes the same basin features originally published in 1988 with some minor corrections and improvements made to feature attribute information. Previously undetected errors have been corrected and are included in this 2006 edition. This data is not updated. Source map scale is 1:24,000.
Online_Linkage: http://www.ct.gov/deep
Larger_Work_Citation:
Citation_Information:
Originator: Marianne McElroy, State of Connecticut, Department of Environmental Protection, Natural Resources Center
Publication_Date: 1981
Title:
Natural Drainage Basins in Connecticut
Geospatial_Data_Presentation_Form: map
Series_Information:
Series_Name: Connecticut Natural Resources Atlas Series
Issue_Identification: Drainage Basins Map
Publication_Information:
Publication_Place: Hartford, Connecticut, USA
Publisher: State of Connecticut, Department of Environmental Protection
Other_Citation_Details:
The Natural Drainage Basins in Connecticut map is published by the State of Connecticut, Department of Environmental Protection, Natural Resources Center in cooperation with the U.S. Geological Survey. The map was funded in part by the Water Resources Council. Map scale 1:125,000.
Online_Linkage: http://cteco.uconn.edu/map_catalog/maps/state/Natural_Drainage_Basins_In_Connecticut.pdf
Online_Linkage: http://cteco.uconn.edu/map_catalog/maps/state/Natural_Drainage_Basins_In_Connecticut_250K.pdf
Description:
Abstract:
Connecticut Local Drainage Basins is 1:24,000-scale, polygon and line feature data that define local drainage basin areas in Connecticut. These relatively small basin areas mostly range from 0.5 to 8 square miles in size and make up, in order of increasing size the larger subregional, regional, and major drainage basin areas. Connecticut Local Drainage Basins includes drainage areas for all Connecticut rivers, streams, brooks, lakes, reservoirs and ponds published on 1:24,000-scale 7.5 minute topographic quadrangle maps prepared by the USGS between 1969 and 1984. Data is compiled at 1:24,000 scale (1 inch = 2,000 feet). This information is not updated.

Polygon and line features represent drainage basin areas and boundaries, respectively. Each basin area (polygon) feature is outlined by one or more major, regional, subregional, and local basin boundary (line) feature. These data include 2,898 local basin area (polygon) features and 8,663 local basin boundary (line) features.

Local Basin area (polygon) attributes include major, regional, subregional, and local basin number, and feature size in acres and square miles. The local basin number (LBAS_NO) uniquely identifies individual basins and is 7 characters in length. There are 2,895 unique local basin numbers. Examples include 6000-00, 4300-00, and 6002-00. The first digit (column 1) designates the major basin, the first two digits (columns 1-2) designate the regional basin, the first 4 digits (columns 1-4) designate the subregional basin, and the first seven digits (columns 1-7) designate the local basin. Note, there are slightly more local basin polygon features (2,898) than unique local basin numbers (2,895) primarily due to a few stream confluences that split the same local basin into two polygon features.

Local basin boundary (line) attributes include a drainage divide type attribute (DIVIDE) used to cartographically represent the hierarchical drainage basin system. This divide type attribute is used to assign different line symbology to major, regional, subregional, and local drainage basin divides. For example, major basin drainage divides are more pronounced and shown with a wider line symbol than regional basin drainage divides.

Connecticut Local Drainage Basin polygon and line feature data are derived from the geometry and attributes of the Connecticut Drainage Basins data.
Purpose:
The polygon features define the contributing drainage area for individual reservoirs, lakes, ponds and river and stream reaches in Connecticut. These are hydrologic land units where precipitation is collected. Rain falling in a basin may take two courses. It may both run over the land and quickly enter surface watercourses, or it may soak into the ground moving through the earth until it surfaces at a wetland or stream. In an undisturbed natural drainage basin, the surface and ground water arrive as precipitation and leave either by evaporation or as surface runoff at the basin's outlet. A basin is a self-contained hydrologic system, with a clearly defined water budget and cycle. The amount of water that flows into the basins equals the amount that leaves. A drainage divide is the topographic barrier along a ridge or line of hilltops separating adjacent drainage basins. For example, rain or snow melt draining down one side of a hill generally will flow into a different basin and stream than water draining down the other side of the hill. These hillsides are separated by a drainage divided that follows nearby hilltops and ridge lines.

Use these basin data to identify where rainfall flows over land and downstream to a particular watercourse. Use these data to categorize and tabulate information according to drainage basin by identifying the local basin number for individual reservoir, lake, pond, stream reach, or location of interest. Due to the hierarchical nature of the basin numbering system, a database that records the 7-digit local basin number for individual geographic locations of interest will support tabulations by major, regional, subregional, and local basin as well as document the unique 7-digit local basin number. To identify either all upstream basins draining to a particular location or all downstream basins flowing from a particular location, refer to the Gazetteer of Drainage Basin Areas of Connecticut, Nosal, 1977, CT DEP Water Resources Bulletin 45, for the hydrologic sequence, headwater to outfall, of drainage basins available at http://cteco.uconn.edu/docs/wrb/wrb45_gazetteer_of_drainage_areas_of_connecticut.pdf

Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.). Not intended for analysis with other digital data compiled at scales greater than or more detailed than 1:24,000 scale. Use these data with 1:24,000-scale hydrography data also available from the State of Connecticut, Department of Environmental Protection.
Supplemental_Information:
A standardized mapping of natural drainage basins in Connecticut was completed in 1981 by the Connecticut Department of Environmental Protection. This drainage basin system divided Connecticut into 8 major basins, 45 regional basins, 337 subregional basins, 2,898 local basins, and 7,067 small drainage basin areas. Major basins are subdivided into regional basins. Regional basins are subdivided into subregional basins. Subregional basins are subdivided into local basins. Local basins are subdivided into smaller drainage basin areas for impoundments and river reaches. 

A pair of 1:24,000-scale polygon and line feature classes is available for all basin levels. These data are named Connecticut Major Basins, Connecticut Regional Basins, Connecticut Subregional Basins, Connecticut Local Basins, and Connecticut Drainage Basins. Connecticut Drainage Basins includes the most detailed information upon which the other basin datasets are based.

A hierarchical drainage basin number was assigned to uniquely identify drainage basin areas. Drainage basin areas are numbered sequentially beginning upstream and proceeding downstream. The first digit (column 1) identifies the major basin, the first two digits (columns 1-2) identify the regional basin, the first 4 digits (columns 1-4) identify the subregional basin, and the first seven digits (columns 1-7) identify the local basin. Below are examples of the hierarchical drainage basin numbers.

Basin Numbers:

4 = Major drainage basin number, MBAS_NO (column 1)
43 = Regional drainage basin number, RBAS_NO (columns 1-2)
4302 = Subregional drainage basin number, SBAS_NO (columns 1-4)
4302-04 = Local drainage basin number, LBAS_NO (columns 1-7)
4302-04-1-R12 = Basin drainage identification number, BASIN_NO (columns 1-13)

Stream Order (column 9):

4304-00-1 = Stream order value of 1 represents a headwater basin.
4304-00-2 = Stream order value > 1 denotes the complexity of the drainage basin morphology.

Mapping Status Element (column 10):

4302-00-2- = Ending with minus sign (-) denotes detail mapping at 1:24,000 scale for entire basin.

4302-00-2+ = Ending with plus sign (+) denotes detailed mapping not performed at 1:24,000 scale for the entire drainage basin. The Stream Order value will not reflect the complexity of the drainage basin morphology.

4302-00-1* = Ending with asterisk sign (*) denotes a headwater basin containing a delineated impoundment into which a delineated drainage basin outlets.

Reach-Impoundment Identifier (column11) and Number (column 12-13):

4302-00-1-L1 = The value for the Reach-Impoundment Identifier for an impounment basin is L (for lake). It is followed by the Reach-Impoundment Number (1).

4302-04-1-R12 = The value for the Reach-Impoundment Identifier for a stream reach basin is R (for reach). It is followed the Reach-Impoundment Number (12).
Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1988
Currentness_Reference:
publication date
Status:
Progress: Complete
Maintenance_and_Update_Frequency: None planned
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -73.760405
East_Bounding_Coordinate: -71.465712
North_Bounding_Coordinate: 42.603944
South_Bounding_Coordinate: 40.936173
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Theme_Keyword: drainage basin
Theme_Keyword: drainage area
Theme_Keyword: watershed
Theme_Keyword: basin divide
Theme_Keyword: major
Theme_Keyword: regional
Theme_Keyword: subregional
Theme_Keyword: local
Theme_Keyword: gazetteer
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: elevation
Theme_Keyword: inlandWaters
Place:
Place_Keyword_Thesaurus: 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.
Place_Keyword: United States
Place_Keyword: Connecticut
Place_Keyword: CT
Place:
Place_Keyword_Thesaurus: U.S. Department of Commerce, 1995, Countries, Dependencies, Areas of Special Sovereignty, and Their Principal Administrative Divisions (Federal Information Processing Standard (FIPS) 10-4): Washington, D.C., National Institute of Standards and Technology.
Place_Keyword: United States of America
Place_Keyword: USA
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 as the source for this information. For example, include the following data source description when printing this layer on a map: Basins - From the Local Drainage Basins layer, compiled and published by CT DEP. Source map scale is 1:24,000.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: State of Connecticut, Department of Environmental Protection
Contact_Person: Tom Nosal
Contact_Address:
Address_Type: mailing and physical address
Address:
79 Elm Street
City: Hartford
State_or_Province: Connecticut
Postal_Code: 06106-5127
Country: USA
Contact_Voice_Telephone: 860-424-3540
Contact_Facsimile_Telephone: 860-424-4058
Contact_Electronic_Mail_Address: dep.gisdata@ct.gov
Hours_of_Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
Browse_Graphic:
Browse_Graphic_File_Name: http://www.cteco.uconn.edu/metadata/dep/browsegraphic/localbasinfullview.gif
Browse_Graphic_File_Description:
Full view of Connecticut Local Drainage Basins - Local Drainage Basin line features are symbolized by the Drainage Basins Divide (DIVIDE) attribute to illustrate the basin hierarchy.
Browse_Graphic_File_Type: GIF
Browse_Graphic:
Browse_Graphic_File_Name: http://www.cteco.uconn.edu/metadata/dep/browsegraphic/localbasindetailview.gif
Browse_Graphic_File_Description:
Detail view of Connecticut Local Drainage Basins - Local Drainage Basins polygon features are labeled with the 7-digit local basin number. Local Drainage Basin line features are symbolized by the Drainage Basins Divide (DIVIDE) attribute to illustrate the basin hierarchy. Watercourses are shown in the background.
Browse_Graphic_File_Type: GIF
Browse_Graphic:
Browse_Graphic_File_Name: http://www.cteco.uconn.edu/metadata/dep/browsegraphic/localbasinmainstem.gif
Browse_Graphic_File_Description:
Detail view of Local Basin main stem - Main stem basins for larger rivers and streams are denoted with two zeros (00) in columns 6 and 7. These local main stem basins receive flow from upstream tributaries.
Browse_Graphic_File_Type: GIF
Data_Set_Credit:
Tom Nosal, State of Connecticut, Department of Environmental Protection, for the final compilation and delineation of 1:24,000-scale drainage basin boundaries, assignment of drainage basin numbers, and conversion to digitial format. Basin boundaries were manually delineated at 1:24,000-scale by visually interpreting the 10 feet contour elevation lines and waterbody features appearing on 1:24,000-scale 7.5 minute USGS topographic quadrangle maps for Connecticut published between 1969 and 1984. The metadata abstract includes a brief description of a drainage basin obtained from material written by Jim Murphy in an article entitled Reading the Landscape published in the Citizen's Bulletin, a CT DEP monthy magazine.
Native_Data_Set_Environment:
These data are maintained by the State of Connecticut using ArcGIS software developed by Environmental Systems Research Institute (ESRI) in a Microsoft Windows operating system environment.
Cross_Reference:
Citation_Information:
Originator: Tom Nosal, Department of Environmental Protection, State of Connecticut (compiler and publisher)
Publication_Date: 19970101
Title:
Gazetteer of Drainage Basin Areas of Connecticut
Geospatial_Data_Presentation_Form: document
Series_Information:
Series_Name: Water Resources Bulletin
Issue_Identification: No 15
Publication_Information:
Publication_Place: Hartford, Connecticut, USA
Publisher: State of Connecticut, Department of Environmental Protection
Other_Citation_Details:
Gazetteer of Drainage Basin Areas of Connecticut is organized by the eight major drainage basins covering Connecticut. The individual basins that comprise each major basin are listed in hydrologic sequence, headwater to outfall, with drainage basin number, description, basin area, and cummulative drainage area listed for each individual basin.
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Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The Drainage Basins layer retains the feature types and information identified on the 1:24,000-scale compilation sheets for the Natural Drainage Basins in Connecticut map, McElroy, 1981. All attributes have valid values. Values are within defined domains. There are no duplicate LBASIN_NO values except where expected (see definition of LBASIN_NO attribute).

The LBASIN_NO is derived from the first 7-digits of BASIN_NO so the accuracy of the LBASIN_NO is dependent on that for the BASIN_NO. For polygon features, the accuracy test for the BASIN_NO attribute values was conducted by visually comparing the basin number information depicted on the source Mylar overlays with 1:24,000-scale check plots or interactive displays of the digital data on a computer graphic system. These check plot maps and computer displays labeled polygon features with BASIN_NO values and differentiated line features based on DBARC_COD values for comparison with the original source Mylars. Subsequently, four additional fields (MBAS_NO, RBAS_NO, SBAS_NO, LBAS_NO) were added and populated based on the first, first 2, first 4, and first 7 columns of the BASIN_NO attribute. The MAJOR, REGIONAL, and SUBREGION attributes store drainage basin names based on MBAS_NO, RBAS_NO, SBAS_NO values, respectively. Basin names were attributed by joining basin name lookup tables to the polygon features base on MBAS_NO, RBAS_NO, SBAS_NO key values and populating the corresponding fields. These basin names are from the Natural Drainage Basins in Connecticut map, McElroy, 1981. The AREA_SQMI (area in square miles) and ACREAGE (area in acres) field were automatically calculated for each polygon feature based on computer generated feature area in square feet.

For line features, the DBARC_COD attribute was populated through a combination of automated and manual processes that compared the BASIN_NO attribute value of the polygon on each side of the line. For example, if the two polygons are in different major basins (MBAS_NO on the left <> MBAS_NO on the right), then the line feature represents a Major basin drainage divide and is assigned a DBARC_COD value of 1. If the left and right polygons are in the same Major basins but in different regional basins (RBAS_NO on the left <> RBAS_NO on the right), the line feature is a Regional basin drainage divide and is assigned a DBARC_COD value of 2, and so on. DIVIDE is the English language equivalent of (decodes) the DBARC_COD attribute value and was populated by joining a lookup table to the line features instead of manually attributing these values for each line feature. AV_LEGEND and IMS_LEGEND values were also attributed through table joins.
Logical_Consistency_Report:
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. Lines are single part. Line features conform to the following topological rules. 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. In general, there are no duplicate features, unresolved intersections, overshooting lines, open polygons, sliver polygons, or unlabeled (unattributed) polygons. 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 0 feet (dangle length).
Completeness_Report:
The data reflects the content of the data source, which is a set of 1:24,000 scale mylar sheets used to compile and publish the 1:125,000-scale Drainage Basins in Connecticut Map, McElroy, 1982. All major, regional, subregional, local and smaller basin divides were digitized from these 1:24,000-scale mylar compilation sheets. This data is not updated.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The horizontal positional accuracy of this data complies with the United States National Map Accuracy Standards for 1:24,000 scale maps. According to this standard, not more than 10 percent of the locations 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.

Drainage basin boundaries were interpolated from 10 FT elevation contours and surface water body (hydrography) information published on a set of USGS 1:24,000-scale, 7.5-minute topographic quadrangle maps that cover the State of Connecticut. Natural drainage basin boundaries were manually delineated by interpolating elevation and water body information found on topographic quadrangle maps published by the USGS between 1962 and 1984.
Lineage:
Source_Information:
Source_Citation:
Citation_Information:
Originator: State of Connecticut, Department of Environmental Protection
Publication_Date: Unpublished Material
Title:
drainage basin compilation sheets
Geospatial_Data_Presentation_Form: stable base mylar
Publication_Information:
Source_Scale_Denominator: 24000
Type_of_Source_Media: stable-base material
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Source_Citation_Abbreviation:
Source 1 - Source Materials
Source_Contribution:
Basins compiled on 1:24,000-scale 7.5 minute USGS quadrangle area mylar overlays.
Source_Information:
Source_Citation:
Citation_Information:
Originator: State of Connecticut, Department of Environmental Protection
Publication_Date: 1988
Title:
Connecticut Drainage Basins
Edition: 2006
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Hartford, Connecticut USA
Publisher: State of Connecticut, Department of Environmental Protection
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 and digitized from the 1:24,000-scale compilation sheets for the 1:125,000-scale Natural Drainage Basins in Connecticut Map, McElroy, 1981. The 2006 Edition includes the same basin features originally published in 1988 with some minor corrections and improvements made to feature attribute information. Previously undetected errors have been corrected and are included in this 2006 edition. This data is not updated. Source map scale is 1:24,000.
Online_Linkage: http://www.ct.gov/deep
Source_Scale_Denominator: 24000
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1988
Source_Currentness_Reference:
publication date
Source_Citation_Abbreviation:
Source 2 - Drainage Basins
Source_Contribution:
Connecticut Drainage Basins is in ArcInfo Coverage format having both polygon and line features. The name of the ArcInfo Coverage is BASIN.
Source_Information:
Source_Citation:
Citation_Information:
Originator: State of Connecticut, Department of Environmental Protection
Publication_Date: 1988
Title:
Connecticut Local Basins
Edition: 2006
Geospatial_Data_Presentation_Form: vector digital data
Publication_Information:
Publication_Place: Hartford, Connecticut, USA
Publisher: State of Connecticut, Department of Environmental Protection
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 and digitized from the 1:24,000-scale compilation sheets for the 1:125,000-scale Natural Drainage Basins in Connecticut Map, McElroy, 1981. The 2006 Edition includes the same basin features originally published in 1988 with some minor corrections and improvements made to feature attribute information. Previously undetected errors have been corrected and are included in this 2006 edition. This data is not updated. Source map scale is 1:24,000.
Online_Linkage: http://www.ct.gov/deep
Source_Scale_Denominator: 24000
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Single_Date/Time:
Calendar_Date: 1988
Source_Currentness_Reference:
publication date
Source_Citation_Abbreviation:
Source 3 - Local Drainage Basins
Source_Contribution:
Connecticut Local Drainage Basins is in ArcInfo Coverage format having both polygon and line features. The name of the ArcInfo Coverage is LBASIN. These polygon and line feature data were subsequently converted to geodatabase feature format and named LOCAL_BASIN_POLY and LOCAL_BASIN_LINE, respectively.
Process_Step:
Process_Description:
Feature digitizing and attribution (digitizing tablet method) - Using ESRI ArcInfo software, basin boundary line features were digitized by registering the individual compilation sheets 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 are used as registration points and are depicted on the source map. The source map 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, basins boundaries features were manually digitized off the source map. 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 orginal source data. These check plot maps were printed at the same scale as the source maps in order to visually inspect digitizing quality and the assignment of attribute values. 

Individual quadrangle level basin boundary coverages were appended and edgematched along quadrangle boundaries to create a statewide layer in ArcInfo Coverage format having both polygon and line features. Polygon label points were created and assigned BASIN_NO values that uniquely identified each polygon feature. Most other related polygon and line feature attributes were assigned through automated procedures based on the format and hierarchical nature of the BASIN_NO value. Four additional fields (MBAS_NO, RBAS_NO, SBAS_NO, LBAS_NO) were added and populated based on the first, first 2, first 4, and first 7 columns of the BASIN_NO attribute. The MAJOR, REGIONAL, and SUBREGION attributes store drainage basin names based on MBAS_NO, RBAS_NO, SBAS_NO values, respectively. Basin names were attributed by joining basin name lookup tables to the polygon features base on MBAS_NO, RBAS_NO, SBAS_NO key values and populating the corresponding fields. These basin names are from the Natural Drainage Basins in Connecticut map, McElroy, 1981. The AREA_SQMI (area in square miles) and ACREAGE (area in acres) field were automatically calculated for each polygon feature based on computer generated feature area in square feet. The GAZRECNO attribute was manually assigned to each basin polygon feature.

For line features, the DBARC_COD attribute was populated through a combination of automated and manual processes that compared the BASIN_NO attribute value of the polygon on each side of the line. For example, if the two polygons are in different major basins (MBAS_NO on the left <> MBAS_NO on the right), then the line feature represents a Major basin drainage divide and is assigned a DBARC_COD value of 1. If the left and right polygons are in the same Major basins but in different regional basins (RBAS_NO on the left <> RBAS_NO on the right), the line feature is a Regional basin drainage divide and is assigned a DBARC_COD value of 2, and so on. DIVIDE is the English language equivalent of (decodes) the DBARC_COD attribute value and was populated by joining a lookup table to the line features instead of manually attributing these values for each line feature. AV_LEGEND and IMS_LEGEND values were also attributed through table joins.
Source_Used_Citation_Abbreviation:
Source 1 - Source Materials
Process_Date: 1988
Source_Produced_Citation_Abbreviation:
Source 2 - Drainage Basins
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: State of Connecticut, Department of Environmental Protection
Contact_Person: Tom Nosal
Contact_Address:
Address_Type: mailing and physical address
Address:
79 Elm Street
City: Hartford
State_or_Province: Connecticut
Postal_Code: 06106
Country: USA
Contact_Voice_Telephone: 806-424-3540
Contact_Facsimile_Telephone: 860-424-4058
Hours_of_Service: Mondy to Friday, 8:30 to 16:30 Eastern Standard Time
Process_Step:
Process_Description:
Create Local Drainage Basins -  Using ArcInfo Workstation software, removed the BASIN_NO polygon feature attribute, calculated the ACREAGE and AREA_SQMI polygon attributes to zero, and dissolved polygon features on the remaining LBAS_NO, SBAS_NO, RBAS_NO, MBAS_NO, SUBREGIONAL, REGIONAL, and MAJOR attribute values to create local drainage basin polygon features. Using the ArcInfo Dissolve command, this step merged the smaller basin polygons into the larger local basin polygon features. Line features were preserved as part of the dissolve process and were merged using the ArcInfo Unsplit command afterwards. The ACREAGE and AREA_SQMI attributes were recalculated based on the new feature geometry, and ArcInfo coveage topology was re-established with the Build command.
Source_Used_Citation_Abbreviation:
Source 2 - Drainage Basins
Process_Date: 1988
Source_Produced_Citation_Abbreviation:
Source 3 - Local Drainage Basins
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: State of Connecticut, Department of Environmental Protection
Contact_Person: Tom Nosal, Howie Sternberg
Contact_Address:
Address_Type: mailing and physical address
Address:
79 Elm Street
City: Hartford
State_or_Province: Connecticut
Postal_Code: 06106
Country: USA
Contact_Voice_Telephone: 860-424-3540
Contact_Facsimile_Telephone: 860-424-4058
Hours_of_Service: Mondy to Friday, 8:30 to 16:30 Eastern Standard Time
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Spatial_Data_Organization_Information:
Indirect_Spatial_Reference_Method:
Connecticut DEP Major Basin Number, Regional Basin Number, Subregional Basin Number, Local Basin Number, Basin Number
Direct_Spatial_Reference_Method: Vector
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: String
Point_and_Vector_Object_Count: 8663
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Spatial_Reference_Information:
Horizontal_Coordinate_System_Definition:
Planar:
Map_Projection:
Map_Projection_Name: Lambert Conformal Conic
Lambert_Conformal_Conic:
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_Coordinate_Information:
Planar_Coordinate_Encoding_Method: coordinate pair
Coordinate_Representation:
Abscissa_Resolution: 0.000250
Ordinate_Resolution: 0.000250
Planar_Distance_Units: survey feet
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1983
Ellipsoid_Name: Geodetic Reference System 80
Semi-major_Axis: 6378137.000000
Denominator_of_Flattening_Ratio: 298.257222
Vertical_Coordinate_System_Definition:
Altitude_System_Definition:
Altitude_Resolution: 1.000000
Altitude_Encoding_Method: Explicit elevation coordinate included with horizontal coordinates
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Entity_and_Attribute_Information:
Detailed_Description:
Entity_Type:
Entity_Type_Label: Connecticut Local Drainage Basin Line
Entity_Type_Definition:
Drainage basin linear features outline all drainage basin polygon features. These line features typically represent drainage basin divides between major, regional, subregional, local, stream reach, and smaller lake impoundment basins. However, some features are not true drainage basin divides. For example, line features that coincide with the coastline enclose coastal basins that drain into Long Island Sound. These line features that follow the coast are encoded as shoreline features.
Entity_Type_Definition_Source:
State of Connecticut, Department of Environmental Protection
Attribute:
Attribute_Label: OBJECTID
Attribute_Definition:
Internal feature number.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Sequential unique whole numbers that are automatically generated.
Attribute:
Attribute_Label: DBARC_COD
Attribute_Definition:
Drainage Basin Arc Code - A numeric code that describes the type of drainage basin divide. There are 9 drainage basins arc code values, one for each type of feature. For example, a drainage basin line feature that forms the boundary between two Major drainage basins has a Drainage Basin Arc Code value of 1 (DBARC_COD = 1); a drainage basin line feature that forms the boundary between two Regional drainage basins in the same Major basin has a Drainage Basin Arc Code value of 2 (DBARC_COD = 2); a drainage basin line feature that forms the boundary between two Subregional drainage basins in the same Regional basin has a Drainage Basin Arc Code value of 3 (DBARC_COD = 3); and so on. Not all linear features represent true drainage basin divides between drainage basins. Some line feature types are introduced in order to close certain polygon features along the data limit or along the coast. For example, line features that are not true drainage basin divides or features that follow the geometry of the (coastal) shoreline have DBARC_COD values of 0 and 8, respectively. When symbolizing drainage basins arc features on DBARC_COD or DIVIDE values, be sure to exclude features not intended to be shown on the map by using the following layer definition query: DBARC_COD > 0.
Attribute_Definition_Source:
State of Connecticut, Department of Environmental Protection
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: 0
Enumerated_Domain_Value_Definition:
Not a drainage basin divide
Enumerated_Domain:
Enumerated_Domain_Value: 1
Enumerated_Domain_Value_Definition:
Major drainage basin divide
Enumerated_Domain:
Enumerated_Domain_Value: 2
Enumerated_Domain_Value_Definition:
Regional drainage basin divide
Enumerated_Domain:
Enumerated_Domain_Value: 3
Enumerated_Domain_Value_Definition:
Subregional drainage basin divide
Enumerated_Domain:
Enumerated_Domain_Value: 4
Enumerated_Domain_Value_Definition:
Local drainage basin divide
Enumerated_Domain:
Enumerated_Domain_Value: 5
Enumerated_Domain_Value_Definition:
Stream reach basin divide
Enumerated_Domain:
Enumerated_Domain_Value: 6
Enumerated_Domain_Value_Definition:
Lake impoundment basin divide
Enumerated_Domain:
Enumerated_Domain_Value: 8
Enumerated_Domain_Value_Definition:
Shoreline - Not a true drainage divide. This line feature is coincident with the shoreline and introduced to close coastal basins draining into Long Island Sound.
Enumerated_Domain:
Enumerated_Domain_Value: 9
Enumerated_Domain_Value_Definition:
State Boundary
Enumerated_Domain:
Enumerated_Domain_Value: 10
Enumerated_Domain_Value_Definition:
Water diversion point divide
Attribute:
Attribute_Label: DIVIDE
Attribute_Definition:
Drainage Basin Divide - Text values that correspond to numeric DBARC_COD attribute values. DIVIDE is the English language equivalent of (decodes) the DBARC_COD field. When symbolizing drainage basins arc features on DBARC_COD or DIVIDE values, be sure to exclude features not intended to be shown on the map by using the following layer definition query: DIVIDE <> "Not a drainage basin divide".
Attribute_Definition_Source:
State of Connecticut, Department of Environmental Protection
Attribute_Domain_Values:
Unrepresentable_Domain:
See Enumerated Domain Value Definitions for DBARC_COD attribute.
Attribute:
Attribute_Label: AV_LEGEND
Attribute_Definition:
ArcView Legend. A text field for symbolizing the different types of drainage basin divides on a map. The AV_LEGEND attribute classifies basin boundary features into the same categories as DBARC_COD and DIVIDE. It is included for convenience. Unlike the IMS_LEGEND attribute, it does not condense features into broader categories. When symbolizing drainage basins arc features on AV_LEGEND values, be sure to exclude features not intended to be shown on the map by using the following layer definition query: AV_LEGEND <> "No Show".
Attribute_Definition_Source:
State of Connecticut, Department of Environmental Protection
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Lake Impoundment
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 6
Enumerated_Domain:
Enumerated_Domain_Value: Local
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 4
Enumerated_Domain:
Enumerated_Domain_Value: Major
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 1
Enumerated_Domain:
Enumerated_Domain_Value: No Show
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 0
Enumerated_Domain:
Enumerated_Domain_Value: Regional
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 2
Enumerated_Domain:
Enumerated_Domain_Value: Shoreline
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 8
Enumerated_Domain:
Enumerated_Domain_Value: Stream Reach
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 5
Enumerated_Domain:
Enumerated_Domain_Value: Subregional
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 3
Enumerated_Domain:
Enumerated_Domain_Value: Water Diversion
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 10
Attribute:
Attribute_Label: IMS_LEGEND
Attribute_Definition:
Internet Mapping Software Legend - A text field used to classify and symbolize basin boundary features into broad categories, more suitable for use with Internet mapping applications. The IMS_LEGEND attribute condenses the 9 drainage basin line feature types (DBARC_COD values) into 6 broader categories (Major, Regional, Subregional, Local, Shoreline, and No Show). When symbolizing drainage basins arc features on IMS_LEGEND values, be sure to exclude features not intended to be shown on the map by using the following layer definition query: IMS_LEGEND <> "No Show".
Attribute_Definition_Source:
State of Connecticut, Department of Environmental Protection
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: Local
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 4
Enumerated_Domain:
Enumerated_Domain_Value: Major
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 1
Enumerated_Domain:
Enumerated_Domain_Value: No Show
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD values 0, 5, 6, and 10
Enumerated_Domain:
Enumerated_Domain_Value: Regional
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 2
Enumerated_Domain:
Enumerated_Domain_Value: Shoreline
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 8
Enumerated_Domain:
Enumerated_Domain_Value: Subregional
Enumerated_Domain_Value_Definition:
This category includes DBARC_COD value 3
Attribute:
Attribute_Label: LENGTH_MI
Attribute_Definition:
Calculated length of feature in miles. Note, LENGTH_MI values are not automatically updated after modifying feature geometry (shape). Values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc.
Attribute_Definition_Source:
State of Connecticut, Department of Environmental Protection
Attribute_Domain_Values:
Unrepresentable_Domain:
Numeric value
Attribute:
Attribute_Label: SHAPE
Attribute_Definition:
Feature geometry.
Attribute_Definition_Source:
ESRI
Attribute_Domain_Values:
Unrepresentable_Domain:
Coordinates defining the features.
Attribute:
Attribute_Label: SHAPE.len
Overview_Description:
Entity_and_Attribute_Overview:
Drainage basin information is comprised of a set of polygon and line features that together describe different types of drainage basins and drainage basin divides.  

Part 1 - Drainage Basin Polygon Features

Information encoded for drainage basin polygon features generally includes drainage basin number and name. Below is a brief explanation of the drainage basin identification number. Use the BASIN_NO attribute to uniquely identify drainage basins. The BASIN_NO is a unique number assigned to each polygon feature. However, in a few instances, two adjacent basin polygon features are assigned the same BASIN_NO when separated by a drainage basin line feature encoded as a Water diversion point divide (DBARC_COD = 10).

Basin Numbers:

4 = Major drainage basin number, MBAS_NO (column 1)
43 = Regional drainage basin number, RBAS_NO (columns 1-2)
4302 = Subregional drainage basin number, SBAS_NO (columns 1-4)
4302-04 = Local drainage basin number, LBAS_NO (columns 1-7)
4302-04-1-R12 = Basin drainage identification number, BASIN_NO (columns 1-13)

Stream Order (column 9):

4304-00-1 = Stream order value of 1 represents a headwater basin.
4304-00-2 = Stream order value > 1 denotes the complexity of the drainage basin morphology.

Mapping Status Element (column 10):

4302-00-2- = Ending with minus sign (-) denotes detail mapping at 1:24,000 scale for entire basin.

4302-00-2+ = Ending with plus sign (+) denotes detailed mapping not performed at 1:24,000 scale for the entire drainage basin. The Stream Order value will not reflect the complexity of the drainage basin morphology.

4302-00-1* = Ending with asterisk sign (*) denotes a headwater basin containing a delineated impoundment into which a delineated drainage basin outlets.

Reach-Impoundment Identifier (column11) and Number (column 12-13):

4302-00-1-L1 = The value for the Reach-Impoundment Identifier for an impounment basin is L (for lake). It is followed by the Reach-Impoundment Number (1).

4302-04-1-R12 = The value for the Reach-Impoundment Identifier for a stream reach basin is R (for reach). It is followed the Reach-Impoundment Number (12).

Part 2 - Drainage Basin Divide Line Features

Information encoded for line features categorizes drainage basin divides (boundaries) for cartographic purposes. Use the AV_LEGEND or IMS_LEGEND attribute to classify and symbolize boundary lines on a map. The AV_LEGEND attribute classifies basin boundary features into the same categories as DBARC_COD and DIVIDE. It is included for convenience. Unlike the IMS_LEGEND attribute, it does not condense features into broader categories. When symbolizing drainage basins arc features on AV_LEGEND values, be sure to exclude features not intended to be shown on the map by using the following layer definition query: AV_LEGEND <> "No Show". The IMS_LEGEND attribute condenses the 9 drainage basin line feature types (DBARC_COD values) into 6 broader categories (Major, Regional, Subregional, Local, Shoreline, and No Show). When symbolizing drainage basins arc features on IMS_LEGEND values, be sure to exclude features not intended to be shown on the map by using the following layer definition query: IMS_LEGEND <> "No Show". Use the AREA_SQMI and ACREAGE attributes to determine drainage basin polygon feature size. These values reflect the area of the respective polygon feature. They do not reflect the cumulative (upstream) drainage area for each basin. Note, ACREAGE and AREA_SQMI values are not automatically updated after modifying feature geometry (shape). These values must be recalculated after features are edited, simplified, generalized, clipped, dissolved, etc.
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Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: State of Connecticut, Department of Enviromental Protection
Contact_Address:
Address_Type: mailing and physical address
Address:
79 Elm Street
City: Hartford
State_or_Province: Connecticut
Postal_Code: 06106-5127
Country: USA
Contact_Voice_Telephone: 860-424-3540
Contact_Facsimile_Telephone: 860-424-4058
Contact_Electronic_Mail_Address: dep.gisdata@ct.gov
Hours_of_Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
Resource_Description: Connecticut Local Drainage Basins Line
Distribution_Liability:
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.
Standard_Order_Process:
Digital_Form:
Digital_Transfer_Information:
Format_Name: Shapefile, Feature Class, ArcInfo Coverage
Format_Version_Number: ArcGIS
File_Decompression_Technique: Zip file
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name: http://www.ct.gov/deep
Fees: An online copy of the data may be accessed without charge.
Custom_Order_Process:
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.
Technical_Prerequisites:
Geographic information sytem (GIS), computer-aided drawing or other mapping software is necessary to display, view and access the information.
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Metadata_Reference_Information:
Metadata_Date: 20120125
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: State of Connecticut, Department of Environmental Protection
Contact_Person: Tom Nosal, Howie Sternberg
Contact_Address:
Address_Type: mailing and physical address
Address:
79 Elm Street
City: Hartford
State_or_Province: Connecticut
Postal_Code: 06106-5127
Country: USA
Contact_Voice_Telephone: 860-424-3540
Contact_Facsimile_Telephone: 860-424-4058
Contact_Electronic_Mail_Address: dep.gisdata@ct.gov
Hours_of_Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Time_Convention: local time
Metadata_Extensions:
Online_Linkage: http://www.esri.com/metadata/esriprof80.html
Profile_Name: ESRI Metadata Profile
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