Skip to main content
ICTD 2023 Main banner
Icon Legend
This session is not in your schedule.
This session is in your schedule. Click again to remove it.
Back

Poster Presentation at the Conference, with a Paper in Conference Proceedings

Transportation Safety

Session: Meet the Author - Poster Session PS-6

1373936 - Safety effectiveness of four leg single lane roundabouts

Friday, June 16, 2023
3:30 PM – 5:00 PM CST
Room: Governor's Grand Ballroom
Salon ABC
TRACK: Poster Presentation with a Paper in the Proceedings
Roundabouts significantly reduce fatal and injury crashes, but may slightly increase property damage crashes. Safety evaluations have been conducted using aggregated data from roundabouts with several geometric and operational configurations. Roundabouts may have different safety effects based on the signal configuration replaced, number of lanes, and location. Limited data has been available to perform safety evaluations for roundabouts with specific configurations. The objective of this study is to spesifically evaluate the safety effectiveness of four leg single lane roundabouts replacing two-way stop controlled, all-way stop control, and signalized intersections in rural and urban locations. From 531 roundabouts in Wisconsin, 64 roundabouts were selected for the evaluation. Geometric (number of lanes and legs), operational (signal control type, speed limit, and average annual daily traffic), and crash data were collected before and after the implementation of the roundabouts. The observational before and after Empirical Bayes method was implemented using Wisconsin specific Safety Performance Functions. The results of the study indicate that single lane roundabouts had a significant reduction in fatal and injury crashes between 39-58% and increase in property damage crashes between 33-87%. Fatal and injury crashes crash reductions are in line with existing literature; however, property damage crash increases are significantly larger than previously recorded.

Learning Objectives:

Attendees can expect to learn the following from this session:
  • Upon completion, participants will be able to implement roundabout safety effectiveness for four leg single lane roundabout
  • Upon completion, participants will be able to consider increase in property damage crashes with roundabout implementations
  • Upon completion, participants will be able to peform benefit cost analyses with more accurate estimates for roundabout safety