Roundabouts
Fort Worth is entering the modern roundabout era...
The Fort Worth Transportation and Public Works Department is leading the implementation of modern roundabouts in the city. In the next few months, modern roundabout projects will be opening, with more projects set to begin construction soon.
A roundabout is one of several types of circular road junctions or intersections at which traffic is slowed down and enters a one-way stream around a central island. These junctions are sometimes called Modern Roundabouts, in order to emphasize the distinction from older circular junction types which had different design characteristics and rules of operation. In the United States, those older designs are commonly referred to as “rotaries” or “traffic circles”.
Statistically, roundabouts are much safer for drivers and pedestrians than both traffic circles and traditional intersections. Roundabouts have shown to reduce fatal crashes by 90 percent, injury crashes by 75 percent, and pedestrian crashes by 30 to 40 percent.
Because low speeds are required for traffic entering roundabouts they are not designed for high-speed motorways (expressways). When such roads are redesigned to take advantage of roundabout principles, steps are taken to reduce the speed of traffic, such as adding additional curves on the approaches.
Large old traffic circles are not modern roundabouts
Roundabouts are not the same as traffic circles or rotaries. Traffic circles or rotaries have high-speed entries, weaving in the circle, low capacity, and many high-speed crashes. Sometimes motorists in the circle must yield to those entering. They are large and challenging to drive — at times a “free for all”.
Modern roundabouts require motorists to yield on entry. There is no weaving. Speeds are low, capacity is high, and crashes are few and minor. They are comfortable to drive, and, if designed well, almost everyone likes them after a trial period.
Entering traffic yields to circulating traffic. Circulating traffic always keeps moving.
Roundabouts are also compact compared to their older traffic circle cousins. Modern roundabouts operate with slower speeds and do not trade off safety for traffic capacity while balancing travel provisions for all users.
Using roundabouts
Observe all standard road rules, including yielding for pedestrians in crosswalks. Remember, roundabout traffic travels one-way.
To safely and efficiently drive a roundabout:
- Slow down when approaching the roundabout.
- Guide signs near the entry to a roundabout show lane designations.
- Yield to traffic in all lanes on your left before entering.
- Stay in your lane to your exit.
Roundabout safety
Roundabouts are the safest type of at-grade intersection. They create slower speeds, fewer conflict points for pedestrians and motorists, and reduced collision angles compared to stop sign or traffic signal control. A national study of intersections converted to modern roundabouts had the following significant findings:
- A reduction in collisions of all types of 40 percent.
- A reduction in injury collisions of 75 percent.
- A reduction in fatal and incapacitating collisions of about 90 percent.
Additionally, roundabouts have been proven to cause the following:
- Reduced delays. Since motorists do not always have to stop, delays and queues are usually less compared to STOP sign or traffic signal control especially at high traffic flows.
- Environmental benefits. With reduced delay, roundabouts lessen noise, air pollution and fuel consumption. This is likely to become an increasingly important consideration in the future. Roundabouts also provide opportunities for traffic calming and speed transition, as well as landscaping and gateway treatments.
- Bicyclist safety. Roundabouts offer a more bicycle friendly experience than traditional intersections.