In Network Screening - Segments, all routes in Wisconsin are subdivided into segments to make network screening easier. This allows you to compare smaller portions of a roadway with similar characteristics in Network Screening rather than evaluating an entire route.
When segmenting a route, a new segment is created each time one or more of the following roadway characteristics changes:
If the Roadway System network changes between a State Highway or Local Road
If the route changes between Divided and Undivided
If the Median Type changes between TWLTL (two-way-left-turn lane) and Other Type/None
When the Number of Through Lanes changes on the route
When a route changes between Urban and Rural (as defined by the 2020 Federal Urban Boundaries)
When a roadway classification changes between Freeway and Non-Freeway
After segments are created following the criteria above, minimum and maximum segment lengths are used to ensure that segments are not too small or too large, based on the following parameters:
Any segment that is less than or equal to 0.05 miles will be added to the smallest adjoining segment.
Any segment that is greater than or equal to 2 miles will be segmented at the 2-mile mark.
How Crashes Are Tied to Segments
In Network Screening, crashes are tied to the segment where the crash occurred based on the geo-location. The following outlines the logic of how these crashes are tied to specific segments.
NOTE: The Network Screening applications display both local road and State Highway segments on a single map.
Local Road Crashes
All crashes on Local Road segments are designated as taking place on the Primary side.
NOTE: For Local Road segments, “Primary” and “Opposite” refer to the direction of traffic flow. This is called “Cardinal” and “Non-Cardinal” for State Highway segments.
State Highway Crashes
Divided roadways within the State Highway Network will have both Cardinal and Non-Cardinal designations. Crashes on undivided State Highway roadways will always be designated as Cardinal.