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This research sought to identify best practices for channelized right-turn lanes (CRT) that better accommodate the safety and accessibility needs of all road users. This was accomplished through a comprehensive literature review, a state-of-the-practice survey of state and local roadway agencies (nationwide and within Minnesota), a review of agency policy and guidance materials (nationwide and MnDOT), and a series of focus group meetings focused on vulnerable road users. Feedback received both from the survey of transportation agencies and the focus group sessions performed as a part of this research suggest that roadway agencies throughout the United States are moving toward proactive policies for the use of CRTs that emphasize safety and mobility for vulnerable road users. This movement is generally based on the concerns for the safety of vulnerable road users outlined in the prior section and commonly includes 1.) minimizing the use of CRTs at urban and suburban intersections and/or 2.) designing new CRT facilities or retrofitting existing facilities with mitigation strategies to improve the safety and accessibility for vulnerable road users. This information was synthesized along with the best practices found in the research literature and agency policy/guidance materials to develop implementation guidance, which is organized within the report as follows: 1.) guidance for use of CRTs based on the project scenario; 2.) traffic control recommendations for CRTs; 3.) recommended design features for CRTs; and 4.) recommended mitigation strategies intended to improve CRT safety and/or accessibility for vulnerable road users.

This Research Summary is part of the final deliverable for Report 2024-31, "Designing Channelized Right-Turn Lanes to Increase Pedestrian and Cyclist Safety."

By the end of 2022, nearly 450 roundabouts were installed on Minnesota roadways. An evaluation of traffic safety at roundabouts published by MnDOT in 2017 showed substantial decreases in fatal and serious injury crashes for all users at intersections after installation of a roundabout. The safety effects of roundabouts are largely due to geometric design practices that reduce the speed of motorized vehicles as they approach and travel through the intersection. The purpose of this evaluation is to determine if the safety effects seen in the 2017 evaluation still apply to roundabouts with higher levels of use by pedestrians and bicyclists. This evaluation conducts a before-after analysis of 95 roundabouts in Minnesota and an analysis comparing roundabouts to untreated intersections. With the installation of a roundabout, this study finds that the before-after analysis results in a 40% decrease in all severity injury crashes for all roadway users, a 70% decrease in fatal and serious injury crashes for bikes and pedestrians, and a 15% decrease in total pedestrian bike and pedestrian crashes. The results of the comparison analyses suggest roundabouts have better safety performance than through-stop and traffic signal-controlled intersections and similar safety performance to locations with all-way stop control. The results of this evaluation thus indicate that roundabouts can be an effective safety treatment for pedestrian and bicycle crashes.