Speeding is one of the top 5 factors in crashes in Minnesota. Prioritizing the most effective methods to encourage safe speeds is critical to maximizing effort and funding to reach zero deaths on our roadways.
In 2019, legislation passed to allow Minnesota cities to establish speed limits for city streets under the city’s jurisdiction without conducting an engineering or traffic investigation.
A new research project, funded by MnDOT and the Local Road Research Board, will use the change in speed limit law as an opportunity to study the effect of speed limit changes on vehicle speeds. After identifying Minnesota cities planning to change speed limits and willing to serve as research partners, a sample of roads will be selected for a before/after study of how changes in speed limits affect vehicle speeds.
By estimating changes in speed distributions that follow speed limit changes, while controlling for trends and possible location-based confounding effects, new information will be produced on where and to what degree speed limit changes are effective. This information will be used to develop guidance on when speed limit changes are likely to achieve the desired effect.
Project Details
- Estimated Start Date: 07/22/2020
- Estimated Completion Date: 06/30/2023
- Funding: Minnesota Department of Transportation and Local Road Research Board
- Principal Investigator: Gary Davis
- Technical Liaison: Victor Lund
Details of the research study work plan and timeline are subject to change.
To receive email updates about this project, visit MnDOT’s Office of Research & Innovation to subscribe.
Crossroads 
I have been living in Seattle the last two years. The speed limits are 20 on residential streets and 25 unless posted faster on bigger roads. The wider roads are either 30 or 35 miles per hour. As a bicyclists and car driver, I appreciate the slower speeds. It is safer with more reaction time and quieter. The time it takes to get somewhere does not change enough to care about.