Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Skip to content
This is a Non-Federal dataset covered by different Terms of Use than

Regional Drainage Basin Set

Metadata Updated: September 15, 2023

See full Data Guide here. Regional Drainage Basin Set:

Connecticut Regional Drainage Basins is 1:24,000-scale, polygon and line feature data that define Regional drainage basin areas in Connecticut. These large basins mostly range from 40 to 400 square miles in size and make up the even larger major drainage basin areas. Connecticut Regional 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 and regional basin boundary (line) feature. These data include 85 regional basin area (polygon) features and 529 regional basin boundary (line) features. Regional Basin area (polygon) attributes include major and regional basin number, and feature size in acres and square miles. The regional basin number (RBAS_NO) uniquely identifies individual basins and is 2 characters in length. There are 44 unique regional basin numbers. Examples include 43, 60 and 61. The first digit (column 1) designates the major basin and the first two digits (columns 1-2) designate the regional basin. Note, there are slightly more regional basin polygon features (85) than unique regional basin numbers (44) due to coastal regional basins defined by series of polygon features located along the Connecticut shoreline. Regional 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 individual major and regional 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 Regional 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 2-digit regional basin number for individual geographic locations of interest will support tabulations by major and regional basin a

Access & Use Information

Public: This dataset is intended for public access and use. Non-Federal: This dataset is covered by different Terms of Use than License: Creative Commons CCZero

Downloads & Resources


Metadata Created Date September 2, 2022
Metadata Updated Date September 15, 2023

Metadata Source

Harvested from Connecticut Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date September 2, 2022
Metadata Updated Date September 15, 2023
Publisher Department of Energy & Environmental Protection
Data First Published 2019-10-28
Data Last Modified 2023-07-03
Category geospatial
Public Access Level public
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 7af4286d-b6a0-40d4-bd09-48ae153389ab
Harvest Source Id 36c82f29-4f54-495e-a878-2c07320bf10c
Harvest Source Title Connecticut Data.json
Homepage URL
Metadata Type geospatial
Old Spatial -73.7348,40.9388,-71.4657,42.5969
Source Datajson Identifier True
Source Hash 706dd19ff742e4f7f498d4372d274d3afdcd9a0060dd5394d11d150328dda7cf
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -73.7348, 40.9388, -73.7348, 42.5969, -71.4657, 42.5969, -71.4657, 40.9388, -73.7348, 40.9388}

Didn't find what you're looking for? Suggest a dataset here.