The Wisconsin Department of Transportation (WisDOT) released new data Tuesday showing that 9 of 20 Milwaukee area freeway segments are so congested that motorists must allow more than twice as much time to consistently complete their trips during peak travel times as they would under uncongested conditions, and two of those are so congested that motorists must allow more than three times as much time to consistently complete their trips during peak travel times as they would under uncongested conditions. The data is contained in WisDOT’s “Travel Time Reliability and Delay” Fall 2015 Report, which details travel time and delay data for urban and rural corridors throughout Wisconsin.

The report uses recorded traffic data to measure the extra time motorists must plan into their trip to be assured of consistent on-time arrival at their destination during congested travel periods. Segments with high multiples of peak vs. normal travel time are considered “unreliable.”

According to the report, the most unreliable trips are for travel on the Milwaukee area freeway system. For travel westbound on I-894 from the Hale Interchange to the Zoo Interchange motorists must allow nearly 17 minutes in the morning hours to consistently complete what is a 5-minute trip without congestion. Travelers on southbound US 45 from the Waukesha County line to the Zoo Interchange must allow 34 minutes in the afternoon for what is a 10-minute trip without congestion. Planning time indexes for other Milwaukee and Madison area freeway segments are summarized in the report.

Delays and their costs are significant. During a one year period, drivers in Wisconsin experienced a total of 12.4 million hours of traffic delay, with a corresponding cost of $387 million. Hours of delay increased 2.8 million hours during the 2015 fall quarter compared to the 2014 fall quarter.   

The addition of I-41 to the delay measure added 132 miles of Interstate to the total reported mileage and accounts for about 46 percent of the increase in delay; the I-41 corridor currently has four improvement projects. 

WisDOT is proposing improvements to relieve congestion on two of the most congested segments in the Milwaukee region: I-94 between the Marquette Interchange and the Zoo Interchange, and I-43 between Glendale and Grafton.

The travel time reliability and delay report is a component of WisDOT’s MAPSS Performance Improvement Program, which measures key information in the five core goal areas of Mobility, Accountability, Preservation, Safety and Service. Further details on travel time reliability and delay performance measures are available on the MAPSS website.