Effect of Centerlines on Prevailing Traffic Speeds on Low-speed, Two-lane, Two-way Roads in Urban Contexts
Need Statement 719
Problem
One element of the Safe System Approach is Safe Speeds. Higher speeds dramatically increase the risk of fatality or serious injury to non-motorized road users, thus there is a strong desire to reduce prevailing speeds in urban areas with likely non-motorized use. Centerlines are essentially required on two-way streets when the ADT is 4000 or greater. MnDOT currently provides centerline pavement markings on all paved roads. Traffic calming and reducing speeds are often requested in areas with high non-motorized traffic use, as well as on roads with residential properties. This research would investigate the effect on prevailing speeds when a centerline is present vs not being present.
Objective
The objective of this research is to understand the influence centerlines have on prevailing speeds. Identify if centerline usage should be reduced on low-speed, two-lane, two-way roads in urban contexts. An additional variable to investigate would be the width of the traveled way.
Strategic priorities
- Safety: Higher speeds dramatically increase the risk of fatality or serious injury to non-motorized road users, thus there is a strong desire to reduce prevailing speeds in urban areas with likely non-motorized use.
Expected outcomes
- New or improved policy, rules, or regulations
- New or improved business practices, procedure, or process
Expected benefits
- Safety : If it is found that removing centerlines reduce the prevailing speeds on low-speed, two-lane, two-way roads in an urban context, MnDOT may develop criteria to not place centerlines on roads that meet certain conditions in order to reduce prevailing speeds. This would improve safety, in particular for vulnerable road users.
Technical advisory panel
- Ethan Peterson, MnDOT Office of Traffic Engineering
- Derek Leuer, MnDOT Office of Traffic Engineering (or designee)
- Mitch Bartelt, Washington County Public Works
- HunWen Westman, City of St. Paul
- Vic Lund, St. Louis County Transportation Department
- Adam Wellner, MnDOT CAV-X