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This service is in mature support as of December 2022. Please replace this service with Local Drainage Basin Set from CT DEEP. https://services1.arcgis.com/FjPcSmEFuDYlIdKC/ArcGIS/rest/services/Local_Drainage_Basin_Set/FeatureServer
Local Drainage Basins
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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.
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.
Local Drainage Basin Direction is a cartographic data product. These point feature must be used with Local Drainage Basin polygon and line feature data. They must not be depicted on maps as simple point symbols without symbolizing them with arrows that take on the appropriate direction. These data do not represent the exact location of basin outlets or stream confluences.
Single Fused Map Cache:
Spatial Reference: 102100
Spatial Reference: 102100
Supported Image Format Types:
Title: Local Drainage Basins
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Comments: A standardized mapping of natural drainage basins in Connecticut was completed in 1981 by the then Connecticut Department of Environmental Protection (DEP). 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. The statewide mapping of natural drainage basins established a hierarchical system of basins based on drainage area size with large major basins subdivided into regional basins, regional basins subdivided into subregional basins, subregional basins subdivided into local basins, and local basins subdivided into smaller and more numerous drainage basin areas. Connecticut Drainage Basins is the most detailed delineation of natural drainage basins available on a statewide basis for Connecticut. It includes watersheds for Connecticut rivers, streams, brooks, lakes, reservoirs and ponds included on 1:24,000-scale 7.5 minute topographic quadrangle maps published by the U.S. Geological Survey (USGS) between 1969 and 1984. These basin units include smaller watersheds that drain into many of the small streams and ponds in Connecticut. These basin areas are the building blocks for the larger local, subregional, regional and major drainage basins defined by the DEP.
Connecticut Local Drainage Basins includes 2,898 drainage basin areas, the majority of which 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. The local basin number (LBAS_NO) uniquely identifies individual local 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 areas delineated (2,898) than unique local basin numbers (2,895) primarily due to a few stream confluences that split the same local basin into two areas.
Included with the local drainage basin boundaries are Local Drainage Basin Directonl arrows that depict the general direction of surface water flow within individual local drainage basins. Particular emphasis is given to directional arrows near the location of local drainage basin outlets where one basin drains into another. These and other arrows along stretches of local drainage basin main stem basins and in coastal basins that drain into Long Island Sound are intended to aid in visualizing the network of local drainage basins in Connecticut. These Local Drainage Basin Direction arrows are classified into three types - Outlet Direction, Main Stem Direction and Coastal Direction. Outlet Direction arrows represent general direction of a river or stream at the local drainage basin outlet. Main Stem Direction arrows represent the stream direction of main stem local basins. Coastal Direction arrows indicate the very general direction of surface water within local coastal basins that drain into Long Island Sound. They are cartographic and do not depict the exact location of basin outlets.
Subject: Drainage basins are comprised of a set of polygon and line features that together describe different types of drainage basins and drainage basin divides.
Keywords: Local Drainage Basin,Drainage Basin,Watershed,Connecticut,Deprecated,Mature Support
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