Community Maps Overview

Each year, thousands of Wisconsin residents are injured and killed in traffic crashes. In an effort to prevent these tragedies, the legislature has established a Traffic Safety Commission (TSC) in every county. These commissions are charged, per Wisconsin statute 83.013 (1), to maintain a map of traffic crashes within their county and to review those crashes on a quarterly basis for general awareness and to provide recommendations for corrective action, as appropriate. Because of the complexity of traffic crashes, the legislature required a breadth of expertise to serve on these commissions. TSC membership creates a collaboration of stakeholders dedicated to reducing injuries and death on their roadways locally, regionally and statewide.

In support of the TSC mission, the Community Maps system was developed by the Wisconsin Department of Transportation (WisDOT) Bureau of Transportation Safety (BOTS) in partnership with the Wisconsin Traffic Operations and Safety (TOPS) Laboratory at the University of Wisconsin-Madison to provide an accessible and timely map of traffic crashes for each county. Community Maps is updated on a nightly basis from the WisDOT crash database management system and includes a record of all police reported crashes* in Wisconsin for which geo-coded locations are available. Crash records that have not been geo-coded are included in the total number of crashes for a given jurisdiction but are not displayed on the map. (For more information, see the Data Sources section below).

* A reportable crash is defined as a crash resulting in injury or death of any person, any damage to government-owned non-vehicle property to an apparent extent of $200 or more, or total damage to property owned by any one person to an apparent extent of $1000 or more. (This definition went into effect 1/1/96). It is important to note, however, that not all reportable crashes are reported. In order for a crash to be in the database, an MV4000 or DT4000 crash report must have been completed by a police officer.

Injury Status

Crash records in Community Maps are categorized in terms of crash injury severity, taken as the highest injury severity level over all persons involved in a crash. Five injury severity levels are defined on the Wisconsin police crash report:

The injury severity level definitions used in Wisconsin changed in 2017 to reflect the 4th Edition of the Model Minimum Uniform Crash Criteria (MMUCC). More information on the MMUCC is available from the National Highway Traffic Safety Administration (NHTSA).

Data Sources

Community Maps is updated on a nightly basis with preliminary crash report information from the Wisconsin DT4000 police crash report database. All police reported motor vehicle crashes are included. Community Maps includes records for all reported crashes since 2010 to the present day. Records for fatal crashes are available since 2001.

In order for a crash location to be displayed on the Community Maps crash map, it must be geo-coded to a latitude and longitude coordinate pair corresponding to the location of the crash on the roadway. Crashes that have not been geo-coded are counted in the total number of crashes returned for a particular search but will not be displayed on the map. Geo-coordinates are taken from the following sources:

For more information, please see the Community Maps TSC Resources area and the WisTransPortal crash data services page.

Contact Information

Community Maps is maintained at the University of Wisconsin-Madison by the Wisconsin Traffic Operations and Safety (TOPS) Laboratory in collaboration with the Wisconsin Department of Transportation (WisDOT) Bureau of Transportation Safety (BOTS). Project contact information is available from the Community Maps Contact page. For technical support, please email

Project History

The Community Maps project was developed through a partnership of the UW-Madison Traffic Information Center (TIC) and the UW TOPS Lab through primary sponsorship of WisDOT BOTS and the Wisconsin Traffic Records Coordinating Committee (TRCC). Development of the initial pilot system was supported by the Midwest Regional University Transportation Center (MRUTC) and the Southwestern Wisconsin Regional Planning Commission (SWWRPC). Joni Graves (TIC) and Steven Parker (TOPS Lab) led the initial development and build-out of the system. In 2017, Community Maps was upgraded to incorporate DT4000 police crash reported locations directly by immplementing a nightly import of crash data from the TOPS Lab WisTransPortal crash database.

Release Version: 1.3.29 (November 11, 2021)