Roundabouts provide a safer way to direct traffic by reducing vehicle speeds and eliminating the need for left hand turns.
Research has shown roundabouts reduce up to 72% of all collisions at an intersection. More importantly, roundabouts have been shown to reduce fatal and injury collisions by up to 87%.
Roundabouts also help keep traffic moving more efficiently by not using stop signs or traffic lights, meaning fewer stops and delays for drivers.
1. What are the traffic rules in roundabouts?Permanent link to What are the traffic rules in roundabouts?
Here is a reminder on how to use a roundabout safely:
- Take a look at this roundabouts diagram (1.6 MB)
- Traffic entering the roundabout must yield to traffic already in the roundabout
- As opposed to uncontrolled intersections, the vehicle on the right must yield to the vehicle on the left
- The driver on the left must signal and use caution when leaving the roundabout
- Pedestrians crossing at marked crosswalks have the right-of-way
- Vehicles entering or leaving the roundabout must yield to pedestrians at the crosswalk
- Watch this video by the Government of Alberta to see the rules in action!
What is the purpose of a roundabout?
The primary function of a roundabout is to manage traffic and assign right of way at an intersection. Roundabouts are a safer alternative for drivers and pedestrians than stop signs or traffic circles. While they have the added benefit of slowing drivers at the intersection, they also prevent unnecessary delay when traffic is light and can improve the efficiency and flow of traffic.
3. Is it allowable to drive over the flat part (truck apron) of the roundabout?Permanent link to Is it allowable to drive over the flat part (truck apron) of the roundabout?
Roundabouts usually have a “truck apron” around the centre island that provides extra room for large vehicles. They are designed to support the weight of large trucks and help long vehicles turn safely. Generally, light vehicles stay on the pavement, but if drivers want to drive on the truck apron, it is not a problem. As long as they pass on the correct side of the centre island, the intersection will still function as intended, assigning right of way to the vehicle in the circle.
4. What do I do if I encounter an emergency vehicle in a roundabout?Permanent link to What do I do if I encounter an emergency vehicle in a roundabout?
- If you are still outside the roundabout: Pull over to the right, when you can do so safely. Let the emergency vehicle pass you before you enter.
- If you are already in the roundabout: Drive to your intended exit. Leave the roundabout completely before you pull over to the right. Then let the emergency vehicle pass you.
5. How do I navigate a roundabout when driving a large vehicle, like an RV or tractor trailer?Permanent link to How do I navigate a roundabout when driving a large vehicle, like an RV or tractor trailer?
Large vehicles may need to mount the truck apron to navigate the roundabout. Roundabouts are designed with this feature in place.
In a two lane roundabout, large vehicles may need to use both lanes when they enter, drive through and exit a roundabout. If this is the case:
- Straddle the entry lanes as you approach the intersection.
- Yield to all traffic in all lanes of the roundabout. Do not enter beside a driver that is already in the roundabout.
- Use both lanes in the roundabout as you pass the first exit. Do not try to keep to one lane so that other drivers can pass you.
- Be sure to signal your intentions to help other drivers understand where you are planning to go.
6. How should pedestrians use roundabouts?Permanent link to How should pedestrians use roundabouts?
Roundabouts are generally safer for pedestrians than traditional intersections. Follow these tips to cross a roundabout safely:
- Use the sidewalks and crosswalks around the outside of the roundabout. Do not cut across the middle of the roundabout.
- Point your finger across the crosswalk to indicate to drivers that you intend to cross. Look and listen for a safe gap in traffic.
- Start to cross as soon as you are sure the driver intends to slow or stop for you.
- Watch for a driver approaching in the next lane if it is a two lane roundabout. Make sure that the driver sees you.
- If there is a centre island, wait there for a safe gap in traffic before crossing to the other side of the road.
- Keep pointing your finger across the crosswalk to indicate to drivers that you intend to cross.
How should cyclists use roundabouts?
If you're an experienced cyclist, you can move through the roundabout the same way you would in a vehicle:
- Merge into the centre of the vehicle lane before the bike lane or shoulder ends
- Stay in the middle of the lane to avoid collisions with other vehicles exiting to the right
- Ensure you use hand signals to let drivers know where you intend to go
If you are not confident navigating the roundabout in this manner, it is best to get off your bicycle and cross the roundabout as a pedestrian.
Transportation Engineering and Operations
Last updated: Monday, November 07, 2022
Page ID: 39119