Some Chicago GIS Data

This page provides links to several ESRI shapefiles for local political boundaries in the Chicago area. The files have been saved as .zip files; to use them you must unzip them. You should end up with .shp, .shx, .dbf, and .prj files.

The unzipped files should run under ArcGIS as well as under the several other mapping programs that can read ESRI  shapefiles. If you are using a mapping program that requires its GIS data to be in a different format, you are going to have to translate these files into that format.

The material was created by the staff of the Map Collection at the University of Chicago. The material may be freely copied, but you should most definitely read the caveats in the notes for each section. You should attribute authorship to the Map Collection, University of Chicago Library, and to the personal authors mentioned in the texts.

It is always a good idea to project Chicago GIS data. Good projections for the Chicago area include the Illinois East state plane projection and UTM Zone 16.

Most of the files accessible on this page were prepared during the 1990s. For more recent data for Chicago only, see, for example, the city of Chicago's list of Chicago GIS files.

Chicago ward map, 1998. This is the ward map for Chicago that was in effect between 1998 and early 2003. The file was derived from the Tiger 1998 voting district file. George Stachokas has edited the file, altering some of the boundaries to make them more closely resemble the boundaries shown in the city of Chicago's published ward maps.

Chicago ward map, 1992. This map was current from 1992 until 1998, when litigation forced some boundary changes. This file contains accurate straight lines in some places where the corresponding street files have inaccurate crooked lines. The author of this boundary file is Christopher Siciliano. It was edited very slightly in 2001 by George Stachokas.

Chicago ward map, 1986. This is the ward map that preceded the 1992 map. The file was generated largely from voting district boundaries (which are numbered by ward) and may consequently contain some minor errors. Christopher Siciliano did a considerable amount of cleaning up of this file.

Community areas. Since the 1920s Chicago has been officially divided into "community areas" of which there are now 77. The sociologists of the Chicago School who divised the community areas attempted to create socially homogeneous regions. In practice, some of the community areas have coincided more clearly with widely recognized neighborhood boundaries than others, and, with time, certain community areas have come to seem particularly artificial. Nonetheless, the City of Chicago compiles many statistics by community area. This file consists for the most part of consolidated tract polygons. Christopher Siciliano corrected these boundaries for those parts of the city--near O'Hare and in two small areas on the South Side--where the tract boundaries do not coincide with community area boundaries.

Police districts. This file gives 1998 boundaries of the districts used by the Chicago Police Department. It is derived largely from the maps at the Police Department's Website (click here for a later version). Author of shapefile: Christopher Siciliano.

1980 census tract boundaries for Northeastern Illinois and Northwestern Indiana. This file contains 1980 tract boundaries modified slightly to facilitate comparison between 1980 and 1990 data. Minor boundary differences between the two census years are ignored, and this fact surely affects the reliability of the comparison in a very few cases. In two parts of the metropolitan area 1980 and 1990 boundaries bear such a complicated relation to each other that "supertracts" were created. These incorporate several 1980 tracts and several (different) 1990 tracts. The attribute table (trct1980.dbf) gives selected 1980 data as well as selected 1990 data consolidated to 1980 tract boundaries. The 1980 data labels are short names that should be interpretable. The 1990 data labels for 1A data are similar to the 1980 names, except that they end in 90. For 3A data, generally, standard 1990 census names are used. Inputting was done by Sunia Abdula. Robert Knippen contributed greatly to the creation of these files.

Chicago city limits. This file corrects several problems in the original TIGER/line files, notably the inclusion of parts of Lake Michigan within the city limits, and the numerous irregularities that are a function of the way the TIGER/line files were created. This file will consequently not line up with TIGER/line streets or tracts; it will line up with the 1992 ward boundary file. Its author is Christopher Siciliano.

Christopher Winters
Bibliographer for Geography, Anthropology, and Maps
JRL 370, (773) 702-8761