General  
Links 
Animations
Video
Oregon Law
Click here to see collected photos of examples of modern roundabouts.

General

Portland's Bureau of Transportation System Management is investigating the use of a modern roundabout at intersections in Portland.  Modern roundabouts differ from traffic circles and have benefits that traditional signalization cannot provide.  Roundabouts are especially useful at reducing the number of angle collisions.  These types of collisions are usually the most costly in terms of property damage, injury and death.  The modern roundabout offers effective intersection traffic control at a reduced life-cycle cost.

The old style, large traffic circle and the modern roundabout that will replace it - Ulster, New York.

For more information on roundabouts and their design:

Links:

FHWA   Roundabout Basics

ROUNDABOUTS: An Informational Guide

Kansas State University at http://www.ksu.edu/roundabouts/

Kittelson roundabouts database at http://roundabout.kittelson.com

ODOT's roundabout page at http://www.odot.state.or.us/techserv/engineer/pdu/roundabout.htm

Ourston and Doctors at http://www.roundabouts.com/

Article by Patrick Siegman at http://www.service.com/PAW/morgue/spectrum/1997_Mar_5.GUEST05.html

Clearwater, Florida at http://t2.ce.ufl.edu/Clearwater/page1.htm

Michael Wallwork http://www.roundabouts.net

Mini-roundabouts - very popular in Europe (the book is pretty good too) at http://members.aol.com/penntraff/mini-roundabout/

Roundabouts USA at http://www.roundaboutsusa.com/intro.html

101/Milipas Interchange, Santa Barbara County at http://www.milpasroundabout.com/index.html

BFJ http://www.bfjplanning.com/resources.htm

Insurance Institute for Highway Safety report (pdf format):
"Crash Reductions Following Installation of Roundabouts in the United States"

Roundabout information:
Center for Transportation Research and Training - Kansas State University

Click here to see collected photos of examples of modern roundabouts.

101/Milipas Interchange, Santa Barbara County at http://www.milpasroundabout.com/automobile.html

Hutchinson, Kansas http://www.ci.hutchinson.ks.us/roundabout.htm

Video:

Washington Department of Transportation
Driving Modern Roundabouts at 
http://www.wsdot.wa.gov/eesc/CAE/designvisualization/video/Portfolio/Modern_Roundabouts/mpg_index.htm

Portland Airport, Portland, Oregon - 1.0 MB

Acacia Roundabout, Clearwater, Florida - 4.6 MB

Kansas State University at http://www.ksu.edu/roundabouts/

Oregon Laws:

801.187 "Circulatory roadway." "Circulatory roadway" means the portion of a highway within a roundabout that is used by vehicles to travel counterclockwise around a central island. A circulatory roadway does not have a crosswalk. [2001 c.464 §3]

801.451 "Roundabout." "Roundabout" means an intersection characterized by a circulatory roadway, channelized approaches and yield control of entering traffic. A roundabout encompasses the area bounded by the outermost curb line or, if there is no curb, the edge of the pavement, and includes crosswalks on any entering or exiting roadway. [2001 c.464 §2]

811.292 Failure to yield right of way within roundabout; exception; penalty. (1) A person commits the offense of failure to yield right of way within a roundabout if the person operates a motor vehicle upon a multilane circulatory roadway and does not yield the right of way to a second vehicle lawfully exiting the roundabout from a position ahead and to the left of the person’s vehicle.

(2) This section does not apply if a traffic control device indicates that the operator of a motor vehicle should take other action.

(3) The offense described in this section, failure to yield right of way within a roundabout, is a Class C traffic violation. [2001 c.464 §5]

Note: 811.292 was added to and made a part of the Oregon Vehicle Code by legislative action but was not added to ORS chapter 811 or any series therein. See Preface to Oregon Revised Statutes for further explanation.

811.400 Failure to use appropriate signal for turn, lane change, stop or exit from roundabout; penalty. (1) A person commits the offense of failure to use an appropriate signal for a turn, lane change or stop or for an exit from a roundabout if the person does not make the appropriate signal under ORS 811.395 by use of signal lamps or hand signals and the person is operating a vehicle that is:

(a) Turning, changing lanes, stopping or suddenly decelerating; or

(b) Exiting from any position within a roundabout.

(2) This section does not authorize the use of only hand signals to signal a turn, change of lane, stop or deceleration when the use of signal lights is required under ORS 811.405.

(3) The offense described in this section, failure to use appropriate signal for a turn, lane change or stop or for an exit from a roundabout, is a Class B traffic violation. [1983 c.338 §634; 1995 c.383 §66; 2001 c.464 §6]

Oregon Revised Statues can be found at http://www.leg.state.or.us/ors/home.html