This file is a digital ARC/INFO GIS coverage consisting of line arcs that indicate greenways and trails in northeastern Illinois which includes Will, McHenry, Cook, DuPage, Kane and Lake Counties.
This dataset includes information such as the type of line arc (greenway or trail/both or neither), whether or not the line arc originated from the 1995 Bikeways Inventory, the type of trail, the width of the trail, the surface composition of the trail, the status of the greenway and/or trail (proposed or existing) and the name of the greenway or trail. (See ENTITY AND ATTRIBUTE DETAIL CITATION for a complete listing of the attributes used).
This dataset was projected using Transverse Mercator and the State Plane Grid Coordinate System 1927 was used. Planar measurements are in survey feet. The geodetic model used is the North American Datum of 1927.
On June 19, 1997, the Northeastern Illinois Planning Commission adopted the "Regional Greenways and Trails Implementation Program", an updated and replacement to the 1992 "Northeastern Illinois Regional Greenways Plan Map". The "Regional Greenways and Trails Implementation Program" was accompanied by a map called the "Map of Greenway and Trail Opportunities and Summary". This dataset, along with two other coverages (see CROSS REFERENCE) were used in the creation of a map called the "Map of Greenway and Trail Opportunities and Summary".
It is required that the Northeastern Illinois Planning Commission be cited in any products generated from the data. The following source citation must be included: "Source: Northeastern Illinois Planning Commission's 1997 Locations of Existing and Proposed Trails and Greenways in Northeastern Illinois, GIS Coverage, Version 1.0, April 2003."
For custom requests a client must submit a written request stating the intended applications for the data to NIPC. When the request is granted, data may be used only for the purposes explicitly stated in the written request. See "Ordering Instructions" for more detail.
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Northeastern Illinois Planning Commission <http://www.nipc.cog.il.us>
Openlands Project <http://www.openlands.org>
Illinois Prarie Trail <http://www.ipp.org/>
This file is a digital ARC/INFO GIS coverage consisting of polygons indicating open spaces in northeastern Illinois which includes Will, McHenry, Cook, DuPage, Kane and Lake County. For this coverage, open spaces are defined as areas of land designated as being Forest Preserve Districts (FPD's) in northeastern Illinois.
Whilst open spaces, defined as FPD lands, constitute the majority of the polygons in this dataset, other open spaces are included. These open spaces include among others, park district lands, federally owned lands and properties under private ownership.
This dataset indicates whether or not the polygon is covered by the Greenways and Trails Plan (see SUPPLEMENTAL INFORMATION for additional information about the Greenways and Trails Plan), the ownership status of the polygon e.g. Federal vs. FPD and the source data for each polygon.
The gird coordinate system for this dataset is State Plane Coordinate System 1927, and the horizontal datum is NAD 27.
The U.S. Environmental Protection Agency's (EPA) River Reach File Version 3.0 (RF3) was used to provide all the line arc features in this coverage. No new line arcs were digitized, but some line arcs were split for the purposes of this dataset. In addition, only a certain number of line arcs were named, not entire river lengths. This coverage contains line arcs with no inherent width, as such, they are conceptual and not prescriptive.
The associated descriptive information (table) indicates the Cataloging Unit (CU), the River Segment (SEG), and Marker Index (MI) separately and combined under an additional attribute item field called RF3RCHID. This dataset also indicates whether or not the river segment is in the Greenways & Trails Plan (see SUPPLEMENTAL INFORMATION for additional information about the Greenways & Trails Plan) and the Illinois EPA's primary name for the river.
Categorizing river segments as part of the Greenways & Trails Plan was a conceptual exercise. THEREFORE, THE GREENWAYS97 ATTRIBUTE IS ONLY SUITABLE FOR PROJECTS OF A CONCEPTUAL NATURE. THE ORIGINAL INTENT OF THIS DATASET WAS FOR MAPPING PURPOSES ONLY, OMISSIONS AND ERRORS THAT DO NOT AFFECT MAPPING ACTIVITIES MAY BE PRESENT.
This dataset was projected using Transverse Mercator and the State Plane Grid Coordinate System 1927 was used. Planar measurements are in survey feet. The geodetic model used is the North American Datum of 1927.
The feature IDs and attributes on lines are ascertained to be very accurate after repeated visual and electronic inspection and repeated usage. Since some municipalities did not assign names to trail systems, all trails in such municipalities were named after their municipalities. Proposed trails were left unnamed, and their other attributes were assigned the value 'unspecified'. Since a minimum of field testing was performed, accuracy of some line codes may be less than 100%. Data collection for points proved difficult, resulting in a loss of quality control of attributes for point features. Inclusion of certain point attributes was not required, although, where available, they were included. Furthermore, there was no feedback mechanism in place to determine the level of completeness. Therefore, the attribute accuracy of the point coverage is hard to assess at this time.Source: Northeastern Illinois Planning Commission's 1995 Non-Motorized Facilities Inventory
For the following attribute labels: BIKES95, GREENWAYS97, INITIALS, DATE, SOURCE, DUMMY, STATUS-GRNWY, STATUS-TRAIL, GNAME, INITIALS2, DATE2, SOURCE2, attribute accuracy is ascertained to be very accurate after repeated visual and electronic inspection and repeated usage. There are however blank fields where values for certain attributes should exist.
There was no systematic sampling of line arcs to be field-checked.
Due to omissions and errors, some trails may not be present in this final coverage. In addition, external to the GIS procedures, a subjective selection process (of trails) was conducted by the various constituents involved in the planning process behind the Greenways & Trails Plan.
The associated attribute table is not complete, values are absent for certain line arcs for certain attributes. This was due to a need to speed up the GIS process to produce a coverage that was sufficient for mapping purposes only. This coverage is complete as of 5 June 1998.
The positional accuracy of lines and points is based on the use of USGS 1:24,000-scale, 7.5 minute source quadrangles, which are compiled to meet National Map Accuracy Standards (NMAS). Therefore, accuracy is no better than that of the source material. Cartographic offsets may be present on the graphic source, due to scale and legibility constraints. Since information was collected on paper USGS 7.5 minute quadrangle sheets, horizontal positional accuracy may be compromised due to instability of the media. Yet while some distortion may be present, it would be minimal, since the horizontal positional accuracy for the digital data was tested visually using paper check plots that were compared to mylar quadrangles, and was corrected.Source: Northeastern Illinois Planning Commission's 1995 Non-Motorized Facilities Inventory
For the remaining line arcs in this coverage, the positional accuracy of the lines and points was based upon a myriad of sources that include USGS Digital Raster Graphics, USGS 1:24 000 scale, 7.5 minute source quadrangle maps, information and maps from County Planning Departments etc. There were many factors that affected the accuracy of the line arcs in this coverage. The main source of error (or uncertainty) was the judgment on our part as to where the line arc should rest. For each line arc, numerous decisions were made. Someone else, using their best judgment, might come up with lines that deviate significantly from ours.
Upon completion of the digitization process, the coverage was then re-projected back to the State Plane Grid Coordinate System, NAD 27, for plotting purposes and for use with other NIPC coverages.
Ders Anderson of the Openlands Project finished checking the trails coverage for all 6 counties. Checks were made to ensure that the shape was GENERALLY correct and that all trails they were concerned about were included. Ders checked the trails coverage against an assortment of 52"x36" maps that included trails, trail names, greenways, 1995 bikeways, NIPC BULA roads, NIPC's Land Use Inventory for 1990, in particular open space, interstate and water, NIPC railroads, Digital Line Graphic (DLG) streams and county lines. The process by which the line arcs in this coverage were coded as being present or not present in the Greenways and Trails Plan was done manually by NIPC staff.
Data Dictionary: Data Dictionary: Northeastern Illinois Planning
Commission's 1997 Locations of Existing and Proposed Trails and
Greenways in Northeastern Illinois, GIS Coverage, Version 1.0,
April 2003.
Attribute Label Attribute Definition Attribute Type
wdth outpt type dec
FNODE# Internal # of from node 4 5 B
TNODE# Internal # of to node 4 5 B
LPOLY# Internal # of left polygon 4 5 B
RPOLY# Internal # of right polygon 4 5 B
LENGTH Length of each arc 8 18 F 5
TRAILS97-01# Internal ARC/INFO number 4 5 B
TRAILS97-01-ID Internal ARC/INFO ID number 4 5 B
NAME Name of trail 30 30 C
STATUS Status of trail 1 1 C
TYPE Type of trail 2 2 C
WIDTH Width of trail 2 2 I
SURFACE Surface material of trail 2 2 C
TEXT Concatenation of TYPE, WIDTH
and SURFACE 10 10 C
BIKES95 Origin of line arc 1 1 N 0
GREENWAYS97 Type of greenway 1 1 N
INITIALS Person digitizing trail 3 3 C
DATE Date of digitizing 6 6 I
SOURCE Source of trail/greenway 50 50 C
DUMMY For tracking purposes 1 1 N 0
STATUS-GRNWY Status of greenway 1 1 C
STATUS-TRAIL Status of trail 1 1 C
GNAME Name of greenway/trail 30 30 C
INITIALS2 Person calculating GNAME 3 3 C
DATE2 Data GNAME was calculated 6 6 I
SOURCE2 Source of GNAME 50 50 C
FNODE#
Attribute Definition: Unique identifier for FROM node of arc
Attribute Domain Values:
Range Domain: FNODE# > 0
TNODE#
Attribute Definition: Unique identifier for TO node of arc
Attribute Domain Values:
Range Domain: TNODE# > 0
LPOLY#
Attribute Definition: Unique identifier of the polygon on the left
side of the arc
Attribute Domain Values:
Range Domain: LPOLY# > 0
RPOLY#
Attribute Definition: Unique identifier of the polygon on the
right side of the arc
Attribute Domain Values:
Range Domain: RPOLY# > 0
LENGTH
Attribute Definition: ARC/INFO's calculation of the length of the
arc in units of projected space (feet, in
this coverage). Dynamic variable. (For your
reference, 5280 feet = 1 linear mile.)
Attribute Domain Values:
Range Domain: LENGTH > 0.170601844582592 < 44077.6724906158
TRAILS97-01#
Attribute Definition: ARC/INFO's internal number
DO NOT CHANGE THIS NUMBER!
Attribute Domain Values:
Range Domain: TRAILS97-01# > 0
TRAILS97-01-ID
Attribute Definition: ARC/INFO'S internal ID number. It is not
recommended that you change this number
Attribute Domain Values:
Range Domain: TRAILS97-01-ID > 0
NAME
Attribute Definition: The name of the trail from NIPC's 1995 Bikeway
Inventory. This may be a community name where
the actual trail name is not known or existing
yet. The names are in mixed case.
Attribute Domain Values:
Unrepresentable Domain:
STATUS
Attribute Definition: Current status of the trail
Attribute Domain Values:
Codeset Domain: "E" = Existing
"U" = Under construction
"P" = Planned
"K" = Unknown
" " = NO DEFINITION
TYPE
Attribute Definition: The type of trail
Attribute Domain Values:
Codeset Domain: "T0" = Unknown
"T1" = One-way off-road trail/path
"T2" = Two-way off-road trail/path
"T3" = One-way lane-striped road
"T4" = Two-way lane-striped road
"T5" = Signed route un-striped road
"T6" = Other
"T7" = One-way signed un-striped on one-way road
" " = NO DEFINITION
WIDTH
Attribute Definition: The width of the trail. If the manuscript
showed a range of width e.g. 4-6 feet, the
value for this field was set at the lower
value, in this example, 4 feet.
Attribute Domain Values:
Range Domain: WIDTH > 0
SURFACE
Attribute Definition: The material used on the surface of the
trail
Attribute Domain Values:
Codeset Domain: "Su" = Unknown
"Sa" = Asphalt
"Sc" = Concrete
"Sl" = Limestone
"So" = Other
" " = NO DEFINITION
TEXT
Attribute Definition: A concatenation of TYPE, SURFACE and WIDTH.
Rather than plot each individual attribute
which is difficult to do without
overlapping, a single character string was
constructed from those attributes. If the
attributes were T2, 8 feet and Sc, the
TEXT value would be "T2Sc8"
Attribute Domain Values:
Codeset Domain: Refer to TYPE, SURFACE AND WIDTH
BIKE95
Attribute Definition: The origin of the line arc
Attribute Domain Values:
Codeset Domain: "0" = Line arc was not part of the Bikeway
Inventory
"1" = Line arc was originally part of the
Bikeway Inventory and has not been
altered
GREENWAYS97
Attribute Definition: Indicates whether or not the line arc is
part of the Greenways & Trails Plan. And,
if so, the type to line arc
Attribute Domain Values:
Codeset Domain: "0" = Not part of Regional Greenway & Trail
Plan
"1" = Regional greenway & trail
"2" = Regional trail without a greenway
"3" = Regional greenway without a trail
INITIALS
Attribute Definition: Initials of person digitizing the trails
and/or greenways
Attribute Domain Values:
Codeset Domain: "hm" = Hubert Morgan
"ks" = Kim Soulliere
" " = NO DEFINITION
DATE
Attribute Definition: Date the line arc was digitized
Attribute Domain Values:
Range Domain: DATE > 0 < 980605
SOURCE
Attribute Definition: Source of trail or greenway spatially
Attribute Domain Values:
Codeset Domain: "ders" = Ders Anderson of Openlands Project.
Location was drafted from multiple
sources of his own.
"NIPC 1990 LUI Lakeshore" = Taken from NIPC's 1990 Land Use
Inventory
DUMMY
Attribute Definition: Temporarily created for tracking purposes.
Can be deleted with "Drop Item"
Attribute Domain Values: NO VALUES GIVEN
STATUS-GRNWY
Attribute Definition: Status of the greenway
Attribute Domain Values:
Codeset Domain: " " = Not a greenway
"P" = Proposed greenway
"E" = Existing greenway
STATUS-TRAIL
Attribute Definition: Status of the trail
Attribute Domain Values:
Codeset Domain: " " = Not a trail
"P" = Proposed trail
"E" = Existing trail
GNAME
Attribute Definition: Name of greenway and/or trail
Attribute Domain Values:
Unrepresentable Domain:
INITIALS2
Attribute Definition: Initials of the person that calculated the
name of the greenway and/or trail
Attribute Domain Values:
Codeset Domain: "ks" = Kim Soulliere
" " = NO DEFINITION
DATE2
Attribute Definition: The date the greenway and/or trail was
calculated
Attribute Domain Values:
Range Domain: DATE2 > 0 < 970415
SOURCE2
Attribute Definition: Source of greenway and/or trail name
Attribute Domain Values:
Codeset Domain: "Ders" = Ders Anderson of Openlands Project has
indicated the name per own multiple
sources
"Greenways Plan 1992" = NIPC's Map of Greenway Opportunities
and Executive Summary
Please send questions or comments to Contact in Metadata Reference Information Section.