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Roundabouts - Video transcript "All About Wisconsin Roundabouts."

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Introduction (00:01:15)

Modern roundabouts are one of the newest types of intersections in the United States. These one-way circular intersections provide a safe and efficient alternative for moving traffic through an intersection.

Since most crashes occur at intersections, local and state officials here in Wisconsin are using modern roundabouts to improve our transportation system.

They’re doing this because modern roundabouts are often safer than traditional intersections. Not only does the design of modern roundabouts reduce the chances of severe collision, it also reduces user delays.

Before getting into details, it is important to define the term “modern roundabout.” Modern roundabouts refers to the type of intersection where drivers yield to the left at entry, enter… go counterclockwise around a center island… and choose an exit.

“Modern roundabout” DOES NOT refer to the much smaller devices like this one placed in the middle of a regular intersection to calm traffic.

Nor does it refer to the old larger traffic circles, sometime called rotaries, which were common years ago in England and along the northeastern coast here in the U.S.

Safer and Efficient (00:03:05)

Learning from earlier designs, engineers have learned how to make modern roundabouts safer and more efficient.

One step engineers have taken in designing modern roundabouts is to reduce the size of the circle. The circular shape is one of the key design elements that provides safety. This circular shape, in engineering terms, reduces conflict points. In layman’s terms, the circular shape is designed to prevent drivers from turning into on-coming traffic—making roundabouts safer than traditional intersections.

Look at this research conducted by the Insurance Institute for Highway Safety, the organization known for issuing safety ratings on cars. They’ve conducted research on 23 traditional intersections that were converted to single-lane roundabouts.

What they found is interesting: converting intersections with traffic signals to roundabouts reduced all crashes by about 40 percent…

… reduced crashes that caused injuries by about 75 percent…

… and eliminated fatalities almost entirely!

Why?

Well, it’s because, at traditional intersections, we see T-bone and head-on collisions — and they’re the ones that tend to be serious.

But T-bone and head-on collisions are nearly eliminated in modern roundabouts, because all traffic is moving in the same direction and at slower speeds. That means any collisions that do occur tend to be side-swipes or other glancing blows, which rarely cause injuries.

Another design element of modern roundabouts is that vehicles entering the roundabout yield to traffic already in the circle. This is done with yield signs at the entrances rather than stop signs or traffic signals, which helps to keep traffic moving at a safe and efficient speed.

How efficient? According to researchers at the Insurance Institute for Highway Safety who studied 10 traditional intersections, they calculated that, if those intersections were converted to roundabouts, each driver would save about a minute — and that the combined savings of all drivers using those roundabouts would be about 325,000 hours {pause} every year!

And since there is no stopping-and-starting, less fuel is used. This same study stated that converting those 10 intersections into roundabouts would save 235,000 gallons a fuel per year.

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Compare that to the typical intersection with traffic lights. How many times have you waited for a red light when not one vehicle came through the intersection?

You can’t sit at a red light at a roundabout — because they don’t have lights! When there’s room for you to enter, you’re in [pause] and out — with almost no delay.

One other design element of modern roundabouts is that the entries are slightly curved. This feature, along with the circle, naturally slows traffic — usually to about 15 to 20 miles per hour. That has a couple of advantages. First, it tends to reduce the force of any collisions that do occur — so there are fewer injuries. Second, with slower traffic in the circle, it’s easier for drivers to enter the roundabout.

Navigating a Single-lane Roundabout (00:01:05)

Driving roundabouts is actually pretty easy to get used to. You just need to follow a few simple rules, stay alert, and pay attention to other drivers.

As you approach a modern roundabout, you’ll see a “Roundabout Ahead” sign.

As with any other intersection, you should watch — and stop — for pedestrians.

The most basic rule of roundabouts is the idea of yielding. The traffic already in the roundabout has the right of way, and entering traffic must yield. So as you approach, be sure to look left.

Most roundabouts have signs in the center island, guiding you in a counter-clockwise direction.

When an opening appears and it’s safe to proceed, enter the roundabout.

Once you’re in the roundabout, keep your place in line — don’t pass.

As you approach your exit, put on your right turn signal. Exit the roundabout — and again watch for pedestrians in the cross-walk.

Remember, when driving through a roundabout: make sure to follow the signs and markings.

Navigating a Multi-lane Roundabouts (00:00:55)

In areas with higher traffic volumes, roundabouts have more than one lane — both on the approach and in the circle itself. Although the driving rules for single-lane roundabouts still apply, there are a few more rules to follow.

In a multi-lane roundabout — just as with any multi-lane intersection — you need to choose the correct lane as you approach. Again, make sure and follow the signs and pavement markings. In this roundabout design…

Use the right lane for a right turn…

…or to go straight ahead.

Use the left lane in one of three ways:

…to go straight ahead…

…to make a left turn…

…or to make a U-turn.

By entering the roundabout using the correct lane, you avoid changing lanes, which is not permitted.

Also, when entering a multi-lane roundabout, make sure to yield to both lanes of traffic within the roundabout.

One last point: cars should not pass trucks within a multi-lane roundabout. Trucks often need to straddle both lanes to navigate the circle.

Trucks, Farm Equipment and Emergency Vehicles (00:01:05)

Sometimes, when agencies are considering building a roundabout, truck drivers and emergency response crews are concerned that they won’t be able to navigate the circle.

To accommodate larger vehicles, modern roundabouts are designed with a raised pavement in the middle—called a “truck apron.” Some people see tire marks there and think the roundabout wasn’t built big enough to handle large vehicles. But that’s not the case. The apron is there just for the trucks and other large vehicles. It gives them the extra room they need — but the raised pavement discourages use by cars.

Interview with two of the following: truck driver, snow plow operator, emergency vehicle driver, farmer. Ask initial perception? What steps taken to reassure? Opinion after installation?

With respect to emergency vehicles, if you’re in a roundabout when one approaches, don’t stop in the roundabout. Drive out of the circle and then pull over.

Pedestrians and Bicycles (00:01:20)

In addition to being safer for motorists, roundabouts offer some particular advantages for pedestrians. First, remember it’s a state law to yield to pedestrians. Notice in modern roundabouts that the crosswalks are farther back than in traditional intersections. Because pedestrians are set back from the circle, drivers can react to the pedestrians first — and then deal with the traffic.

The islands between the lanes in the approach to a roundabout also contribute to safety because pedestrians only have to cross traffic one direction at a time.

Also, because traffic speed is reduced, crashes involving pedestrians tend to be less harmful. Lastly, research has shown that more than half of all crashes involving pedestrians also involve left turns — but there are no left turns in a roundabout. To go left, you actually make a right to enter the circle and a right to exit.

Bicyclists have two options.

They can continue through the roundabout taking the travel lane and riding close to the middle of the lane to prevent cars from passing and cutting them off.

If a bicyclist doesn’t want to ride through the roundabout, they should enter the sidewalk using the ramps and proceed as a pedestrian.

Conclusion (00:00:55)

As we’ve seen here, modern roundabouts are one option being considered by public officials at many locations across the Badger State.

In many situations, roundabouts have big advantages. They save time…and more importantly, by reducing crashes, they save lives.

Additionally, they’re easy to drive through. Remember: slow down, follow the traffic signs, move into the correct lane for the direction you want to travel, yield to pedestrians and bicyclists as you enter and exit the roundabout, look left and yield to traffic already in the roundabout, enter when it’s safe, once in the roundabout, you have the right-of-way, keep your speed low within the roundabout, exit carefully by turning right onto your destination street.

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If you’d like more information about modern roundabouts, here are some good places to look.

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Questions about the content of this page:
Pat Fleming, patrick.fleming@dot.wi.gov
Last modified: May 2, 2014

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