Understanding Roundabouts

Charlotteown RoundaboutCharlottetown Roundabout
Navigating a Roundabout
Passenger Vehicles Roundabout SignPassenger Vehicles - When approaching a roundabout observe posted signage, slow down, stay right of the splitter island and yield to pedestrian using the crosswalk. - At the entry point, look to the left and yield right-of-way to any traffic in the roundabout. - Do not block the crosswalk if another vehicle is waiting at the yield line in front of you. - Do not pass any bicyclists who are permitted to ride within the roundabout just as other vehicles. - Once you have entered the roundabout, proceed in a counter-clockwise direction having the right-of-way over other traffic looking to enter. - Use your right-turn signal and exit to your desired street. - Be cautious and yield to any pedestrian using the crosswalk at your exit; there will be a car length between the roundabout circle and the crosswalk.
Trucks Trucks - In the roundabout cars should travel on the outer paved portion only. - Tractor-trailer trucks are longer and the rear wheels track to the inside of a turn; the inner concrete apron has a mountable curb and is intended for the trailer portion of the truck to ride up on as it negotiated the roundabout. - A tractor trailer would start with its front wheels close to the left-side splitter island and then when in the circle and confident that the rear trailer wheels will clear the right-side entry curb, the front tires should be to the outer portion of the circle while the rear wheels will track up on the inner concrete apron; when exiting the front tires should again be close the left-side splitter island for the rear wheels to clear the right-side exit curb.
Cyclist Cyclists - If you are comfortable riding in slower traffic merge with vehicle traffic and circulate like you are a vehicle, making sure to yield to traffic when entering. -This in-line arrangement is preferable to side-by-side travel where cyclists and vehicles are not always able to view each other, as easily and there may be conflicts with a vehicle seeking to exit while the bicyclist beside it intends to continue around. -If you are unsure about using a roundabout per vehicle traffic operations, you should dismount and walk your bicycle as a pedestrian at the designated crosswalk.
Pedestrian Pedestrians - Use the designated crosswalks at street entry points; never cross to the central island. - Watch for vehicles and signal your intent to cross. - When you are certain that traffic to your left will be yielding to you, cross the splitter island which offers some refuge between the two directions of traffic, then concentrate on the traffic to your right and complete the remaining portion of the crossing.

History and Modern Use of Circular Intersections
Circular intersections have long been in use around the world, with design and operations continually being reviewed and altered for improvements. In the early stages of use, traffic volumes were relatively limited and traffic flow rules loosely defined, with different operating practices in different jurisdictions (merging traffic, entering yield, circulatory yield, etc). As traffic volumes increased in North America the use of circular intersections fell out of practice, while in Europe and other areas the use continued with changes and modifications to develop a circular intersection that functions appropriately for current conditions. North America in recent decades has begun to return to the circular intersection for some applications with adaptive change in driving skills required but success in efficiently moving traffic. The most significant change from older circular intersections to those of current day is that traffic entering now yields to vehicles already in the circle; as opposed to early operations of traffic in the circle yielding. As there will be vehicles exiting the circle, this creates gaps for new vehicles to enter. Generally traffic will always slow for a roundabout but steadily flow though rather than the stop-and-wait of traffic signals. The modern roundabout is also a specifically designed intersection for the urban application and has different radius, speed and volume designs and characteristics suited to urban driving than other circular traffic alignments sometimes call rotaries or traffic circles.
Things To Know

Benefits - Reduces injury accidents by 75 percent and fatal accidents by 90 percent. - Increases efficient traffic flow up to 50 percent. - Helps the environment by reducing carbon emissions by double digits. - Decrease fuel consumption by as much as 30 percent. - Life-cycle costs are less than traffic signals without electronics purchase, operation and maintenance.
Traffic Rules
- the rules of traffic signals are numerous and complex for a first time description - red, right on red, amber, green, protected left arrows, permissible lefts, etc; for a roundabout there is simply one basic rule - yield to traffic already in the roundabout
Low Speeds
- slow to the advisory speed (25km/h); reduced speed mean less damage in the event of any collisions
Less Information to Absorb
- drivers have basically one direction (left) to concentrate on as opposed to observing for traffic from the left, straight and right at a signalized intersection
Pedestrian Refuge - the splitter islands provide a pedestrian refuge and allow for concentration on one direction of traffic at a time
Conflict Points
- the number of pedestrian and vehicle conflict points in a roundabout configuration versus a 4-way intersection is significantly reduced; similarly head-on or T-bone vehicle accidents are basically eliminated with sideswipe orientations the main possibility.

Overview of Modern Roundabouts

Compared to traffic signals, roundabouts offer the following advantages:

Reduced Delays - Cars only have to yield at the entrance to a roundabout, rather than stopping and waiting for a green light at a signalized intersection, this keeps things moving. This means shorter average queues and fewer cars blocking driveway entrances. When traffic volumes are low, motorists experience almost no delay, regardless of what direction they arrive from and where they are going.
Increased Capacity
- Traffic capacity is higher due to the continuous flow of a roundabout compared to the wait at yellow and red lights. If multiple drivers are trying to turn left, a roundabout can handle this much more quickly than lights.
Reduced Speed
-Drivers have to slow down to negotiate a roundabout, but motorists don't slow down when they see a green light. Permission to proceed through a roundabout is always the same, regardless of when a motorist gets to it so there isn't the temptation to step on the gas to catch a green or yellow light.
Improved Safety
- There are only eight points in a roundabout where two cars could collide and 32 at a set of lights. This, combined with reduced speeds, reduces the frequency and severity of traffic accidents. Environmentally Responsible - Reduced delays mean reduced fuel consumption and harmful emissions, which improves air quality and motorists' gas mileage. Noise pollution is also reduced because of lower speeds, and less stopping and starting.
Reduce Maintenance Costs
- Roundabouts eliminate the costs associated with electricity, maintenance, and signal timing optimization that traffic signals require.
Aesthetically Pleasing
- The roundabout centre island provides an opportunity for landscaping and community beautification, and the splitter islands may be planted with grass or flowers.
Pedestrian Access and Safety - Crosswalks are placed away from the edge of the roundabout, so motorists encounter pedestrians wither before they arrive at the roundabout or after they leave it, tomes when they are not preoccupied with navigating through the intersection. Also, pedestrians are move visible to approaching drivers and they cross only one direction to traffic at a time, with a refuge area on the splitter island in the middle. Crossing distances are greatly reduced because there are fewer approach lanes at a roundabout. These advantages, combined with reduce speeds, results in drivers being more willing to yield to pedestrians and a better overall pedestrian experience.
Bicycle Access
- Cyclists may choose to either walk their bicycle across the crosswalks like a pedestrian (this is recommended for less experienced riders), or ride through the roundabout as a vehicle.

SRoundaboutlow down to the posted limit Let vehicles already circulating go ahead Obey all one way signs Watch for pedestrians, bicyclists, emergency and large vehicles

To see a video on using a Roundabout, please visit the PEI Transportation & Infrastructure Renewal website.

The City of Charlottetown thanks the traveling public and local businesses for their patience during construction and maintenance activities for road improvements.