Truck Priority

Project Description

This study was undertaken by Mn/DOT to determine if there were ways to improve the operation of heavy trucks passing through traffic signal controlled intersections on rural high-speed highways. The focus of this study was to determine if there was a safe and cost effective way to grant trucks priority treatment at these intersections.

The intersection of T.H. 169 and Laredo Avenue in Belle Plaine was selected as the test intersection. This location was picked because it did not have an existing isolated traffic signal without advance warning flashers and the truck volumes were high at about 2400 per day.

Three methods for improving truck operation were investigated:

• Improving signal timing
• Adding vehicle detectors that would respond only to trucks
• Adding variable message signs to advise all mainline drivers of a speed to use to reach the intersection during the time the signal is green