The New Roundabout

A number of people have questioned the lane markings at the new roundabout. The short answer is that the markings are consistent with the accepted traffic engineering guidance, but an optional improvement could be implemented. Specifically, on the two-lane approaches to the roundabout, the left lane is marked with a left turn arrow on the pavement. The right lane has a right-turn arrow and a straight arrow. These pavement markings are correct (and yes, the Thompson Drive roundabouts are marked the same way).

Here are the latest roundabout marking guidelines approved by National Committee on Uniform Traffic Control Devices (NCUTCD) the folks who develop and refine the Manual on Uniform Traffic Control Devices (MUTCD). The MUTCD (or MUT-Cud as we like to call it at work) sets forth the required traffic signing and marking practices for the entire US.

Nonetheless, a concern has been raised that some drivers may try and turn left into the roundabout with dire consequences. I would note that driver would have to ignore the one-way signs posted at each entrance point and that turning left into a roundabout violates the intuitive sense that one develops after driving a few roundabouts. Still, I would agree that the left-turn marking does not convey the message clearly and that is a must for traffic signs and markings.

Roundabouts are still pretty new in the US and the manuals that traffic engineers use are evolving. One suggestion that the city of Monona could consider is a ‘fish-hook’ left-turn marking where the arrow loops out in the shape of a fish hook with a dot painted inside the loop. The idea is to inform motorists they have to drive around the inner circle before they can to that place over on the left . The picture is not exactly what we would need, but it's the best I could find.

Here’s some handy general guidance for driving roundabouts from the Springfield, Oregon web site. I would add one word: practice. Roundabouts are different and humans need a little repetition to learn new stuff.

Going left or U-turn:
1) When approaching the roundabout, you must be in the left lane unless otherwise marked on the road.
2) Yield to pedestrians in the crosswalk.
3) Yield to traffic in the roundabout.
4) Enter the roundabout when there is a safe gap in the traffic.
5) Stay in the left lane (NEVER change lanes or stop in the roundabout).
6) Use your right turn signal and exit the roundabout.

Going Straight:
1) When approaching the roundabout you can be in either lane unless otherwise marked on the road.
2) Yield to pedestrians in the crosswalk.
3) Yield to traffic in the roundabout.
4) Enter the roundabout when there is a safe gap in the traffic.
5) Stay in your lane (NEVER change lanes or stop in the roundabout).
6) Use your right turn signal and exit the roundabout.

Going right:
1) When approaching the roundabout, you must be in the right lane unless otherwise marked on the road.
2) Yield to pedestrians in the crosswalk.
3) Yield to traffic in the roundabout.
4) Enter the roundabout when there is a safe gap in the traffic.
5) Stay in the right lane (NEVER change lanes or stop in the roundabout).
6) Use your right turn signal and exit the roundabout.