The Oregon Department of Transportation, local jurisdictions and consultants continue to look for traffic control methods that provide ways to safely manage the flow of traffic, bicycles and pedestrians through intersections large and small. Roundabouts are one such method.
Guidance for Designers
Roundabout Design Calculator - For each approach, the roundabout calculator produces conflict flow, entry flow, capacity, pedestrian impedance factors, v/c ratio, control delay, level of service and 95th percentile queue.
"Roundabouts: A safer choice" Presentation, 2010
"Modern Roundabouts for Oregon" Research paper, 1998
Resource site, Federal Highway Administration
Guidance for Roundabout Users
Frequently asked questions about driving and cycling through a roundabout
Check out our Flickr album with photos of roundabouts on Oregon highways.