CT ECO Basic Data Guide

Federal Open Space

Example of Federal Open Space properties


Federal Open Space contains parcels of open space land owned by various agencies of the Federal government. It includes parcels owned in fee simple interest and partial interest, such as easements. Types of Federal open space include recreation areas created by the U. S. Army Corps of Engineers in the construction of flood control dams, such as Mansfield Hollow, Thomaston Dam, Colebrook River Lake and Hop Brook Lake; portions of the Appalachian Trail in northwest Connecticut owned by the National Park Service; and scenic and preservation easements, such as the scenic easements located along the Housatonic River in Kent, Cornwall and Canaan, and along the Connecticut River.


Use this information to view open space land that is owned by the Federal government. Federal Open Space can be used with other related cadastral or parcel level data such as protected open space, statewide trails, DEP Property, DEP boat launches, and land parcels collected for the DEP protected open space mapping project. It can also be used with a variety of environmental data to assess and analyze critical habitats, natural diversity database areas, soil conditions, wetland soils, fisheries management areas, geologic and other environmental conditions at or nearby Federal Open Space.

Use Limitations

This is the best digital information available statewide of Federal Open Space, but it is not positionally accurate and may not be complete. Compiled from land records and maps on file at DEP, there may be obvious and not so obvious omissions and inaccuracies with this information. The Federal Open Space data is not meant to be used for legal boundary purposes. Some Federal Open Space parcels may be missing or positioned incorrectly. Most parcel boundaries were created at 1:24,000 scale using the U.S. Geological Survey Topographic Quadrangle maps as a base and will not align accurately with features such as roads shown on aerial photography. None of the Federal Open Space parcel boundaries were created using a more accurate technique such as using course and distance information from A-2 certified boundary survey maps. This informatation is not meant to be used at map scales larger and more detailed than 1:24,000 scale (1 inch = 2,000 feet).

Dataset Information

  • Status - This datalayer is complete and is not updated.
  • Date of Data - Refer to the Citiation Publication date in the GIS Metadata for the date of the data currently available online.
  • Map Scale and Accuracy - The information meets horizontal National Map Accuracy Standards for 1:24,000-scale mapping (1 inch = 2,000 feet).

Additional Documentation

  • Federal Open Space - CT ECO Complete Resource Guide
  • GIS Metadata – Contains technical documentation describing the Federal Open Space data and the data sources, process steps, and standards used to collect, digitize, and store this information in a geographic information system (GIS).


GIS Data Download

  • Federal Open Space data is downloadable from DEEP GIS Data.
  • Connect GIS and AutoCAD software to this information online using the Open Space CT ECO Map Service.