Federal Open Space is a polygon feature-based layer that includes land owned in either easement or fee simple interest by the federal government. This layer is based on information that was collected and mapped at various scales and at different levels of accuracy. Types of property in this layer include open space and recreational land open to the public. Examples include National Park Service land, Army Corps of Engineers land, etc.
Please note that this data layer has not been updated since 2004 and, as such, may contain inaccurate feature boundaries or attribute information. There are no plans to update this layer at present.
ground condition
Federally owned open space land (Source: Connecticut Department of Environmental Protection)
Feature geometry. (Source: ESRI)
Name of the Federal facility or the Federal Agency that owns the facility. (Source: Connecticut Department of Environmental Protection)
Abbreviation for Conservation/Development. This field contains the category of ownership of the parcel feature. (Source: Connecticut Department of Environmental Protection)
| Value | Definition |
|---|---|
| EXIST | Existing Preserved Open Space. Represents parcels owned in fee simple interest by the Federal government. |
| PRES | Preservation Area. Represents parcels of land that are partial interests (easements). |
Feature geometry. (Source: ESRI)
Internal feature number. (Source: ESRI)
Includes polygon features for all Federally owned open space property such as National Park Service land, Army Corps of Engineers land, etc. Information about these features includes the NAME attribute (facility name and/or owner of the property) and the CD attribute (property ownership type classification). Use the CD attribute to symbolize features by ownership type on a map. Ownership type consists of two values: EXIST denotes Existing Preserved open space owned in fee simple interest and PRES denotes Preservation Area that is easement ownership only.
James Bogar, Cartographer 1994 to 1997; Howard W. Sternberg III, Environmental Analyst 1994 to 2000
79 Elm Street
Federal Open Space contains property that comprises federally owned land. This layer can be used with the DEP Property and Municipal and Private Open Space layers for a more comprehensive understanding of open space and recreation land throughout the State of Connecticut. This layer has not been updated since 2004 and may not be accurate. For more accurate and current open space parcel data, please see the Protected Open Space and the Protected Open Space Phase 1 feature classes. Although the data in those feature classes is more accurate, it does not include any easements; it contains only land owned in fee simple interest. For easements, continue to utilize the Federal Open Space feature class, with the knowledge that it is older data and is subject to verification in municipal land records.
The maps contain the boundaries of the parcels that are owned by the federal government. They provide the source for parcel features in this layer. Scales are not consistent among maps.
Federally owned property delineated at 1:24000 scale from hand drawn delineations on topographic maps, survey maps and sketches.
Federally owned property in an ArcInfo coverage format (NAD27).
Federally owned property in Shapefile format (NAD83).
Federally owned property in geodatabase format.
The Federal Open Space feature class in the Property geodatabase was converted to an ArcSDE feature class.
Create 1:24,000-scale Federal Property Mylars - The initial Federal Open Space Coverage was based on information mapped and subsequently digitized from a series of 1:24,000-scale Mylar overlays maintained by the State of Connecticut, Department of Environmental Protection (DEP). The following briefly describes a mapping effort comprised of delineating the outer property boundary of Federally owned property. This was an ongoing mapping effort at DEP in the 1980's and 1990's. The Federal Open Space Property Mylar overlays for each 1:24,000-scale, 7.5 minute topographic quadrangle map were made by placing a blank sheet of 2 millimeter Mylar on each topographic quadrangle map and manually drafting the neat lines (boundaries) of the topographic quadrangle map on the Mylar. The neat lines were drafted in India ink and are the basis for manually registering (lining up) the overlay to the corresponding topographic quadrangle map. These overlays were not prepared with the intent of creating a data source for digitizing. Rather, they were meant to be used with and the basis for other 1:50,000 and 1:125,000 scale-overlays for regional assessments of dedicated open space, acreage calculations, and map publication purposes. These Mylars were susceptible to expansion and contraction under varying humidity conditions due to a 2-millimeter thickness. Also, the neat lines drawn on the overlays registered each overlay to the paper topographic quadrangle map and not a stable-base Mylar of the topographic quadrangle map. All boundaries for property federally owned and depicted on 1:24,000-scale, 7.5 minute topographic quadrangle maps available in the 1970's and 1980's were transferred to Mylar by registering the overlays to the topographic quadrangle maps and tracing the property boundaries published on the USGS topographic quadrangle maps. Polygon areas were delineated on the overlays to represent Federal Properties. Each polygon was labeled and matched to the quadrangle neat lines, if necessary. All line work was done in ink. Up until 1997, additions and modifications were made to the Property Mylar overlays by incorporating information from the DEP Land Acquisition Division. Two sources of information from the DEP Land Acquisition Division were available: (1) Hand drawn DEP parcel delineations made on a master set of 1:24,000-scale, 7.5-minute topographic quadrangle maps, and (2) Survey maps or sketches provided to the DEP Land Acquisition Division by the federal government. Both data sources varied in accuracy and quality due to a lack of standards for the acquisition of parcels prior to the 1990's. Nevertheless, the best information available from either of these two data sources was used to update the Property Mylars. For example, when property was acquired and a survey map was available, the boundary was traced with a planimeter to produce a 1:24,000-scale representation of the parcel on a small piece of tracing paper. Using a light table, the parcel delineated on tracing paper was then positioned onto a topographic quadrangle map by lining up, as best as possible, parcel boundaries with features (roads, rivers, stone walls) that appeared both on the original survey map and topographic quadrangle map. The Property Mylar overlay was then registered to the topographic quadrangle map in order to update the corresponding Federal Property mylar. The parcel was either drawn on the mylar as a separate polygon area or merged with a polygon of previously acquired property.
Create 1:24,000-scale Federal Open Space Property Coverage - The initial Federal Open Space Property Coverage was based on information mapped and subsequently digitized from a series of 1:24,000-scale Mylar overlays maintained by the State of Connecticut, Department of Environmental Protection (DEP). The following briefly describes the process to digitally capture the information from the Federal Open Space Mylars: The Federal Open Space Property Coverage was first created in 1994 using information from the 1:24,000-scale Mylar overlays. The process of creating the coverage involved developing and testing methods to accurately register the Federal Open Space Property Mylar overlays to a digitizing tablet; digitize boundary lines delineated on the overlays that do not coincide with other 1:24,000-scale base-map features (roads, streams, shorelines and town boundaries); use linear features from 1:24,000-scale base-map layers (road, streams, shorelines and town boundaries) as data sources when coincident with property boundaries; edge-match boundaries along quadrangle neat lines; append boundary lines to form and close polygon features; and attribute polygon features. Line feature topology was established with ArcInfo Fuzzy and Dangle tolerances verified at 4 and 10 feet, respectively. Polygon feature topology was established to ensure that no polygons overlapped. Digitizing was performed using PC ArcInfo 3.4d. All other processing tasks were accomplished using either ArcInfo 5 or 6. Polygon attributes distinguish Federal facilities from one another and include the NAME field to identify the properties. The CD field classifies properties by type: Existing Preserved or Preserved Easement Area. This layer has not been updated since its publication due to no new Federally owned parcels having been acquired within the state.
Datum Conversion - Using ESRI ArcInfo software, the Federal Open Space Property layer was converted from the Connecticut State Plane Coordinate System of 1927 (NAD 27) to the Connecticut State Plane Coordinate System of 1983 (NAD 83). The NADCON (North American Datum CONversion) data transformation was used. A shapefile was then created from the coverage for use with ArcView 3.x.
Federal Open Space converted to geodatabase format.
The Federal Open Space Property geodatabase feature class was converted to an ArcSDE feature class.
Attributes in the Federal Open Space layer have valid values. Values are within defined domains. SHAPE_AREA and SHAPE_LENGTH are the feature area and length in feet and are software calculated.
The overall positional accuracy level is only as accurate as can be established using tablet digitizing onto 1:24,000 scale topographic quadrangle maps.
The completeness of the data reflects the best available federal parcel acquisition records within the State of Connecticut Department of Environmental Protection. However, there may be omissions due to file errors, incomplete files, missing files, or staff error in the file retrieval process. No indication of completeness percentage is possible.
Polygons conform to the following topological rules. Polygons do not self overlap. The ArcInfo Clean function was used to verify topology and enforce a minimum distance between vertices of 4 feet (fuzzy tolerance) and a minimum allowed overshoot length of 10 feet (dangle length). Polygons may overlap. No ArcInfo Build and Clean functions were applied.
None. There are no restrictions or legal prerequisites for using the data. Once acquired, any modification made to the data must be noted in the metadata. When printing this information on a map or using it in a software application, please acknowledge the State of Connecticut, Department of Environmental Protection as the original source for this information.
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| Data format: | in format Shapefile, Feature Class (version ArcGIS) |
|---|---|
| Network links: | http://www.ct.gov/deep |
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.
79 Elm Street