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Roundabouts
What Is a Roundabout?
A modern roundabout is a circular intersection where drivers travel counterclockwise around a central island. It is engineered to maximize safety and minimize traffic delay, and there are no traffic signals. The entering traffic yields to traffic already in the roundabout, which keeps traffic from locking up and creates efficient traffic flow.
How to Drive in a Roundabout
- Slow before entering. This allows you to anticipate gaps in traffic, and lets drivers in the roundabout know you are preparing to yield.
- Yield to drivers circulating from the left. Look left for vehicles before reaching the yield line. If no vehicles are coming from the left and no pedestrians are in the crosswalk, there is no reason to stop.
- Once you are in the roundabout, you have the right of way and entering traffic must yield to you.
- Stay to the right of the central island. Traffic moves counterclockwise in a roundabout.
- Watch for bicycles and pedestrians when exiting the roundabout, and use your right turn signal to indicate you are exiting.
How to Drive in a Mini-Roundabout
- Yield on entry and move in a counterclockwise direction, just like a full-size roundabout.
- Use a turn signal before entering a mini-roundabout if turning left or right onto a side street. If continuing on the same street, no signal is needed.
- Signaling before entering improves efficiency because of the tighter constraints and shorter reaction times compared to a full-size roundabout.
Benefits of Roundabouts
Modern roundabouts have been shown to:
Modern roundabouts have been shown to:
- Keep traffic moving. Roundabouts reduce stopping, delays, and backups.
- Reduce the number of accidents. Studies also show that accidents at modern roundabouts are typically minor due to lower traffic speeds, and the possibility of dangerous t-bone and head-on collisions is virtually eliminated.
- Reduce vehicle emissions due to decreased idling times.
- Typically cost less to construct than signalized intersections, and eliminate the cost to power and maintain traffic signals.
- Increase pedestrian safety. Pedestrians only cross one direction of traffic before reaching a median.
- Increase green space around and within the center island and along approaching streets. Roundabouts minimize the number of lanes needed to move the same amount of traffic compared to a traditional signalized street network.
Current Roundabouts
- 1st Avenue & Holiday Road
- 12th Avenue & Forevergreen Road
- 12th Avenue & Holiday Road (mini-roundabout)
- Commerce Drive & Commercial Park
- E. 7th Street & E. 2nd Avenue
- E. 9th Street & Quarry Road
- E. 9th Street & E. 2nd Avenue
- Heartland Drive, west of Heartland Place
- Holiday Road & Corridor Way
- Oakdale Boulevard & Jones Boulevard
- University Court & Ridgeway Drive
- University Parkway & University Court
- 1st Avenue & Oakdale Boulevard
Mini-Roundabouts vs. Full-Size Roundabouts
- Mini-roundabouts function just like full-size roundabouts, but are used where space doesn't allow for a full-size modern roundabout.
- Mini-roundabouts have a smaller footprint and can often be constructed within an existing intersection.
- Mini-roundabouts have a smaller, paved central island with a lower curb. This allows long vehicles that require a large turning radius, like a semi or bus, to drive over the central island.
- Full-size roundabouts have larger, landscaped central islands which are not traversable.
Contact Us
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Scott Larson
City Engineer
Email1512 7th St.
P.O. Box 5127
Coralville, IA 52241Ph: 319.248.1720
Fx: 319.248.1894