Part of the education process is studying what has been done to see what lessons can be learned. The following project overviews are presented to help you explore some of the challenges associated with constructing modern roundabouts in locations where they are new to local drivers.

Modern roundabout design is still evolving. A design that works well in one community, or in a particular location, may not work well in another. Engineers begin with solid fundamentals (Access to a PDF download of Roundabouts, an Informational Guide, a publication of the Federal Highway Administration -&- A website companion), and then design the roundabout for the conditions at the particular intersection. Sometimes it is necessary to go back and fix individual elements based on experience with local drivers, maintenance methods, or local weather conditions.

Below we present a few modern roundabout installations and their evolution.

AROUND THE U.S.

• Kingston, New York
• Clearwater, Florida

PHOTOS ONLY

• Bruhl Germany

Other Roundabout Experiences

AROUND THE U.S.

An old-style (nonconforming) traffic circle was located at a junction that brings together Washington Avenue, Col. Chandler Drive, the Thruway exit and State Route 28.

The Problem:
The high speeds and weaving maneuvers in the old-style old traffic circle were associated with problems common to those intersections. With a diameter of 600-feet, traffic moved at high speeds and there was an average crash rate of 8 accidents per month.

The Solution:
The old-style traffic circle was replaced with a modern roundabout. The 200-foot diameter roundabout handles all the left turns much more efficiently, and the three bypass lanes allow many other motorists to avoid the intersection entirely.

[ Move mouse over below photo to see the change.]

The new intersection opened during construction in December 2000 before all the striping, signs and lighting work could be completed. In that condition, the roundabout drew criticism. Some folks said they should "rip it up and put the old one back." Of course, all the local pundits weighed in. Read what others are saying about the Kingston roundabout.

Once the work was completed and the improved crash rates became apparent, the negative feedback dissipated very quickly.

The Design Evolution:
The modern roundabout is now functioning very well. NYDOT has stated that there were only five collisions in the first month after opening and two in the second month. After six months in operation, the collision rate averaged 2.8 per month, a great improvement over 8 crashes per month recorded in previous years.

Traffic volume has remained constant at 36,000 vehicles per day.

Kingston Links

Clearwater Beach Entryway in Clearwater, Florida

The Problem:
Clearwater Beach is located on an island that is separated from downtown Clearwater by the Intercoastal Waterway. It is a very popular tourist destination. In previous years, getting to Clearwater Beach required navigating a street network that consisted of nine intersections, three of which were signalized. The traffic volume in the area fluctuated seasonally between 30,000 to 42,000 vehicles per day. Locals believed that traffic congestion in the area discouraged tourists and they wanted to maintain the beach as a prime tourist destination. They decided to make some changes.

The Solution:
The whole network of streets was reconfigured. Six of the nine intersections were reconfigured into a roundabout. The remaining three intersections were converted into T-intersections. A large fountain was constructed in the center of the roundabout as part of the "beach gateway" theme.

[ Move mouse over graphic below to see the change ]

The Design Evolution:
Once the roundabout opened it received mixed reviews.

On the positive side:

• The roundabout is very efficient. Although designed for only 32,000 vehicles per day, on March 12, 2000, a 12-hour pedestrian count recorded over 6,091 pedestrians at the same time 55,996 vehicles used the roundabout. It greatly reduced the traffic snarls that had been common each year during spring break.
• While more vehicle crashes occurred than anticipated, all the roundabout crashes were minor, low seed collisions.
• There have no pedestrian accidents at the roundabout even though the pedestrian volumes are high.

On the negative side:

• Ocean breezes caused the fountain to splash windshields of vehicles in the roundabout.
• The collision reduction was not as expected, however, statistics pointed to two exits, both two-lane exits, that were causing the problem.

Soon after the problem was identified, changes were made to improve the performance. For example, the roundabout had a large number of vehicle crashes at the 2-lane exits onto the Causeway and at the exit into Coronado Drive. Many of those crashes involved cars continuing around the circle in the right lane colliding with drivers exiting from the left lane. In July 2001, revisions to curbs, signing, striping, and lane arrows were introduced that resulted in a significant drop in number of crashes. For example, at the Causeway exit crashes dropped from a high of 25 per month. At last report, there have been no crashes at this location since the changes were made.

Clearwater folks are still working on resolving the fountain issue.

• Wall Street Journal
• Barry Crown's response to the Wall Street Journal article
• St. Petersburg Times - More roundabouts in the St. Petersburg area
• St. Petersburg Times - Includes photograph of roundabout after changes.
• St. Petersburg Times - Fountain Demolition
• Florida Technology Transfer Quarterly - The Clearwater Beach Roundabout: A Balanced Evaluation Experience - Large PDF File

More photos of Clearwater, Florida and roundabout

PHOTOS OF ROUNDABOUTS

Bruhl, Germany

OTHER ROUNDABOUT EXPERIENCES

Keck Circle in Montpelier, Vermont - The report you can access below contains a description of Montpelier's modern roundabout at Keck Circle and results of a public opinion survey conducted in January 1997 for the roundabout constructed in 1995.

The survey was conducted to 1) determine public opinion one year after opening and 2) determine the likes and dislikes to assist the Montpelier Public Works Department and City Council on ways to improve the roundabout. Read the public survey results. (92 KB PDF File)