For more current road information, including downloadable GIS data, refer to the Illinois Department of Transportation Technology Transfer Center (IDOT T2 Center) at <http://dot.state.il.us/blr/t2center1.html>.
Data were derived from the US Geological Survey 1:100,000 Digital Line Graph files, transportation layer, 1980-1986. Publication dates of the USGS maps used as sources range from 1980 to 1986. Major highways were updated as of 1993. The maximum estimated error in horizontal position based on National Map Accuracy Standards is 167 feet. Attributes include up to three state route numbers.
The data are stored in geographic coordinates, NAD83.
These data have not been updated since 1993, nor are there current plans to do so.
This metadata file was originally written by staff of the INHS. Maintenance of the metadata was transferred to ISGS circa 1996.
This dataset serves as an important base cartographic element for many types of maps and has been widely distributed and used outside the ISGS. The data set was not and is not intended as a substitute for surveyed locations, such as can be determined by a registered Public Land Surveyor. Although useful in a GIS as a reference base layer for maps, the data set has no legal basis in the definition of boundaries or property lines.
Any access to these data, Web sites, computer systems, electronic services, and electronic networks is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice.
Links to these are provided in the Cross References section.
Individuals or entities may make fair use of copyrighted ISGS material, such as reproducing a single figure or table, or using a brief text quotation, without obtaining formal permission, but in all cases the Illinois State Geological Survey must be credited as the source of the material. To reproduce ISGS information beyond the fair use standard, permission must be obtained from the ISGS Information Office, 615 East Peabody Drive, Champaign, Illinois 61820, 217-333-4747, isgs@isgs.illinois.edu. License fees and a license agreement may be required, depending on the proposed usage.
Any use of these data is governed by University and campus policies, in particular, but not limited to, the Policy on Appropriate Use of Computers and Network Systems at the University of Illinois at Urbana-Champaign, the ISGS Terms of Use document available at the ISGS Web site, and the University of Illinois Web Privacy Notice. Links to these are provided in the Cross References section.
Map information is to be used at a scientifically and cartographically appropriate scale, that is, at a scale no greater than indicated on the map or as described in the documentation of the map or map data. Map information is not appropriate for, and is not to be used as, a geodetic, legal, or engineering base. Map information has no legal basis in the definition of boundaries or property lines and is not intended as a substitute for surveyed locations such as can be determined by a registered Public Land Surveyor.
The data do not replace the need for detailed site-specific studies.
For more current road information, including downloadable GIS data, refer to the Illinois Department of Transportation Technology Transfer Center (IDOT T2 Center) at <http://dot.state.il.us/blr/t2center1.html>.
Field names including the pound-sign character were renamed to eliminate that character (not allowed by Oracle). The STATE# field contained up to 3 route designations for any given line. It was dropped and the route numbers were segregated into existing field STATE_1 and new fields STATE_2 and STATE_3.
Spatial index grid size was set at 0.9 degrees.
Metadata was updated.
STATE_1, STATE_2, and STATE_3 The value is equal to the designated number of the route. Three fields are used to account for areas where several routes overlap. A line may have up to three numerical designations. Any route having a value for STATE_2 or STATE_3 should also have a value for STATE_1. All lines have at least one route number. Values are from DLG files, 1980-86, USGS and IDOT county base map series.
Disclaimer of Liability Disclaimer of Warranties and Accuracy of Data Disclaimer of Endorsement Disclaimer for External Links Disclaimer of Duty to Continue Provision of Data Security Choice of Law
By obtaining these data you agree to the provisions of the University of Illinois Web Privacy Policy, regardless of the manner in which the information was obtained.
Illinois Natural Resources Geospatial Data Clearinghouse
Generated by mp version 2.8.25 on Wed Apr 08 08:29:03 2009