Permissive left turns, where a driver does not have a green arrow and must wait for a gap in oncoming traffic before turning, can be indicated by different traffic signal configurations. Flashing yellow arrows are becoming a preferred signal type in Minnesota and across the nation. New research provides traffic engineers with confidence that drivers understand the meaning of the signal, even without an accompanying Left Turn Yield sign.
Continue reading Drivers Correctly Interpret Flashing Yellow Arrows for Left TurnsCategory Archives: Traffic and Safety
Reevaluating City Speed Limits with Public Safety in Mind
A recent legislative change has given Minnesota cities greater authority to set lower speed limits on streets in their jurisdiction—a decision that could potentially have positive impacts on public safety, especially pedestrian and bicycle traffic. A recent analysis of speed-setting practices and the effectiveness of speed limit changes resulted in a decision-making process for changing speed limits and alternative strategies to improve pedestrian and bicycle safety.
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New Project: Complete Streets Speed Impacts
Minnesota Statutes §174.75 requires the MnDOT to follow a complete streets approach in all phases of planning, project development, operation, and maintenance activities. The purpose of the MnDOT complete streets policy “is to address the safety and accessibility needs of users of all ages and abilities. MnDOT assesses user needs at several stages of planning, project scoping and designing, construction, operation, and maintenance.”
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Improving Driver Yielding to Pedestrians at Intersections
Improving the rates of drivers yielding to pedestrians has been challenging despite crosswalk laws. Expanding on an earlier study, researchers further explored the effectiveness of engineering treatments at road crossings, giving agencies a deeper understanding of how to maximize pedestrian safety.
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Impact of Urban Speed Limit Changes on Driving Speeds
Speed limits are a popular safety measure used in urban areas. A new analysis that monitored driving speeds before and after posted changes to speed limits reveals lower speed limits may not, at least initially, cause drivers to slow down.
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Increasing Support for Innovative Traffic Solutions
When a transportation innovation shows potential for significantly increasing safety, implementation may seem like the obvious next step. But without public support, a project can be met with resistance that results in delays, additional costs and a lost opportunity to save lives.
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Developing Smart Signs for Traffic Control in Work Zones
Providing traffic control in work zones is one of the highest risk jobs in the country. Flaggers are often considered the first line of defense against distracted, inattentive or aggressive motorists who may intrude into these work areas. A new, cost-effective system that tracks an oncoming vehicle’s trajectory can warn workers of an unsafe intrusion into the work zone and alert drivers to slow or stop.
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Improving and Expanding the Queue Warning System
Combining real-time traffic data, vehicle trajectories and computer algorithms allows queue warning systems to trigger traffic warnings on overhead message signs that alert drivers to congestion or crashes ahead. A recent study evaluated the warning system previously installed on a segment of Interstate 94 (I-94) and deployed the system in a second location, providing an improved understanding of its efficacy and considerations for expanding its use.
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Guidance for Cities Considering Speed Limit Changes
The issue of reducing speed limits to increase public safety is an emotional, political, and controversial topic that has been debated by safety advocates, engineers, politicians, transportation officials, and the public for many years. A statutory change in 2019 put a spotlight on the topic, requiring a deeper look into how speed limits are established and the effectiveness that lowering speed limits has on reducing vehicle traveling speeds, as well as the impacts on pedestrian and bicycle traffic.
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Impacts of Lane Conversions on Level of Service
Reconfiguring roadways, also referred to as a “road diet,ˮ can be a low-cost safety solution that makes space for different travel modes in addition to motor vehicle traffic. New guidance gives local engineers an initial indication of whether a road conversion would result in a loss of capacity given the roadway motor vehicle traffic demand.
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