Roundabouts increase traffic capacity and reduce injury accidents
Roundabouts are a fairly common in Washington State, particularly in areas surrounding the Puget Sound. The City of Tumwater currently has a total of 5 roundabouts, with plans for additional roundabouts in the future. According to the Washington State Department of Transportation, studies conducted by the Federal Highway Administration have found that roundabouts can increase traffic capacity by 30 to 50 percent compared to traditional intersections. Studies also show that roundabouts reduce the rate of injury accidents by 75 percent and the number of fatalities by a projected 90 percent. With a goal of being both accommodating towards urban growth while maintaining an environmentally sustainable city, roundabouts are a perfect fit for the City of Tumwater.
How to drive in a roundabout
As you approach a roundabout, you will see a “roundabout ahead” sign with an advisory speed limit for the roundabout.
- Slow down as you approach the roundabout, and watch for pedestrians in the crosswalk.
- Continue toward the roundabout and look to your left as you near the yield sign and dashed yield line at the entrance to the roundabout. Yield to pedestrians and traffic already in the roundabout.
- Once you see a gap in traffic, enter the circle and proceed to your exit. If there is no traffic in the roundabout, you may enter without yielding.
- Look for pedestrians and use your turn signal before you exit, and make sure to stay in your lane as you navigate the roundabout.
Trucks and oversized vehicles in roundabouts
Roundabouts are designed to accommodate vehicles of all sizes, including emergency vehicles, buses, farm equipment and semi-trucks with trailers. Oversized vehicles and vehicles with trailers may straddle both lanes while driving through a roundabout.
Many roundabouts are also designed with a truck apron, a raised section of pavement around the central island that acts as an extra lane for large vehicles. The back wheels of the oversize vehicle can ride up on the truck apron so the truck can easily complete the turn, while the raised portion of concrete discourages use by smaller vehicles.
Because large vehicles may need extra room to complete their turn in a roundabout, drivers should remember never to drive next to large vehicles in a roundabout.
WSDOT has prepared a five-part video series on YouTube about driving in roundabouts:
- Roundabouts: What they are, and what they are not.
- How do I drive a roundabout?
- Pedestrians and cyclists
- Safety Benefits
- What do roundabouts mean for me?
The above information has been made available by the Washington State Department of Transportation. For further information on roundabouts, please visit their website.