2001 Redistricting Reference Data


A large amount of reference data is needed to draw political districts. This data can be divided into two main groups: numeric and geographic. The numeric component includes items such as population and voter registration values. The geographic component includes features such as roads, rivers, and political boundaries that can be graphically displayed as features on a map.

The numeric data matches up with the geographic data at several different levels. The main levels of interest in district drawing are counties, voter precincts, and census blocks. These three main levels have a nesting relationship. In other words, counties are comprised of voter precincts that, in turn, are comprised of census blocks. Each level covers the entire territory of the state, such that there is no point within the state's boundaries that cannot be assigned to each of the three levels.

All information on this page corresponds with the General Assembly's 2001 redistricting database.

There were three main types of numeric data in the 2001 redistricting database:

Population Data - by April 1st of the year following each decennial census, the US Census Bureau provides Public Law 94-171 data to each of the states. This data corresponds with block level geography, the lowest level tabulated by the Census Bureau, and that at which districts are ultimately defined. The Public Law 94-171 data contains only race and ethnicity breakdowns of total and voting age populations.

Voter Registration Data - the State Board of Elections provided registration information for all voter precincts in the state as recorded in their State Elections Information Management System (SEIMS). In this data set, vintage February 2001, registered voters are broken down by party, race, gender, and age group.

Election Returns Data - also provided by the State Board of Elections at the voter precinct level, information is included for various contests from the 1998 general, 2000 primary, and 2000 general elections.

Complete numeric data sets, as processed for use in the General Assembly's redistricting system, are linked below for download. The field layout definition is required to interpret the information. All data files are in comma-delimited format. Due to their relatively large sizes, four of the six files have been compressed, or "zipped". Make sure to read over the data processing notes for details on how registration and elections data were integrated. Note that although registration and elections data are available at all levels for system consistency, they are most reliable at the precinct and county levels since the original data was precinct-based.

The geographic data in the General Assembly's 2001 redistricting system was based on the "Redistricting Census 2000" TIGER/Line Files provided by the US Census Bureau. Below are links to various statewide layers extracted from that dataset. The voter precinct layer was updated to include precinct splits too recent to make it into the official TIGER release. These files are intended for use with geographic information system (GIS) software. Layers are in shapefile format. The shapefiles are unprojected (coordinates in decimal degrees of latitude and longitude) and based on North American Datum 1983. Due to their relatively large sizes, and the fact that each "shapefile" consists of a group of files, all layers have been compressed. See the attribute documentation for more detailed information about each layer.

Comma Separated Value (*.csv), is a simple text format consisting of values separated by commas. It is easily imported into spreadsheet and database programs, with each line of the file corresponding to a table row, and each item in a line corresponding to a table column. It can also be viewed with text editor programs such as NotePad or WordPad.

Shapefile. This is a spatial data format created by ESRI. Each "shapefile" is actually a collection of several files, each with the same name, but a different file extension. These files are used with geographic information system (GIS) software.

ZIP. Due to large size, some of the files linked from this site have been compressed or "zipped". In addition to native support in some operating systems, a variety of commercial and open source programs exist that can extract ".zip" files.