Modern Roundabouts ~ Users Guide

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First of all, learn what a modern roundabout looks like and what it is designed to do.

Functioning as one way circular intersection without stop lights, this form of intersection control directs traffic to flow around a center island in a counterclockwise pattern.

Secondly, learn what you need to do.

Because a modern roundabout functions as a circular intersection, you need to know where you are going. Just as you need to know where you are going when approaching a normal intersection.


Drivers making right hand turns need to get in the right hand lane and use turn signal following pavement markings and signage.	Drivers making left hand turns need to get in the left hand lane and use turn signal following pavement markings and signage.
	Successfully driving roundabouts involves a third set of rules. They are very important, so let us move on to rules of the road . . .
Drivers going straight ahead should use the same lane that they entered in.


YIELD: THE “GOLDEN RULE” OF MODERN ROUNDABOUTS
While the modern roundabout is on the road to becoming as popular in the United States as it is in Europe, Australia and other parts of the world, there was some initial reluctance to adopt this proven traffic management option. The lack of acceptance can generally be attributed to problems encountered with traffic circles and rotaries built 60-70 years ago. In large part, these problems were due to straight entrances, high speeds, and the right of way being granted to entering vehicles who would try and merge with circulating traffic.
	The most important feature of the modern roundabout -- and one that contributes to greater safety -- is its golden rule: Yield at entry to circulating traffic.

YIELD INSTEAD OF MERGING
	Yield means the other drivers in the traffic lanes have the right of way. An approaching motorist has to wait for a gap…a break…to appear in the flow of traffic before entering. A good way to remember this rule is 'Wait for the Break'. Let’s review the difference between YIELD and MERGE. As opposed to yield, merge means that each vehicle takes a turn. Traffic should slow down to let you enter. This is not the case with a modern roundabout.
While yielding to motorists already circulating in the roundabout, keep an eye on traffic to make sure there is adequate space for you to enter. If there is enough space, enter quickly at the appropriate speed -- 15-25 mph. Do not hold up the traffic behind you. So Go, Go -- Fast or Slow.

“SO WHO DOES HAVE THE RIGHT OF WAY?"

This question is often asked when it is pointed out that those motorists already in the roundabout have the right of way. Motorists waiting to get in the modern roundabout need to YIELD rather than trying to merge. That means wait for a gap in the traffic, then take your turn and proceed.
(Of course all motorists must always be mindful of pedestrians and bicyclists.)

	The right of way is observed at the yield sign. You need to slow down or stop to yield to any traffic approaching from the left. Remember the golden rule: You never merge. All motorists approaching a roundabout must yield. The lane you choose will take where you want to go.
	The right of way involves emergency vehicles. For instance, if a fire truck and/or ambulance enters the roundabout, exit if possible. If not, pull over immediately.
	Pedestrians have the right of way when entering the crosswalk.
	When encountering large trucks, give them plenty of space.

HOW DOES A MODERN ROUNDABOUT WORK?

A modern roundabout is a type of circular intersection without traffic lights Modern roundabouts require all motorists to yield at the entry way.

Before entering, they must reduce speeds to approximately 15-25 mph. In addition to avoiding accidents, these slow speeds help vehicles maintain smooth movement entering, circulating, and exiting.

Safe and efficient traffic flow is also enhanced by entering traffic yielding the right of way to circulating traffic. (As a matter of fact, studies have shown significant improvements in traffic flow following conversion of traditional intersections to modern roundabouts.)

The Alaska Roundabout Web site has excellent information on Myths & Facts about Roundabouts.

HOW TO DRIVE A MODERN ROUNDABOUT

When approaching a modern roundabout, you need to know where you’re going Just as you would when approaching a traditional intersection. You need to use turn signals to let the other drivers know your intentions.

To drive a modern roundabout, you need to remember the following guidelines:

	Slow down - when entering a roundabout, speeds must drop to 15-25mph.
	Let vehicles already circulating go ahead (yield). You never merge. All motorists approaching a roundabout must yield.
	Obey all the signs.
	Watch for pedestrians, bicyclists, large trucks and emergency vehicles.

The ADOT Modern Roundabout Video
Request a DVD	English	Spanish
Introduction 2:25 minutes
Full Length 8:10 minutes
	Video Script (file size: 73KB)	Video Script (file size: 49KB)

For multiple lane usage, heed the following guidelines depending on traffic patterns:

	Drivers making right hand turns need to get in the right hand lane and use turn signal following pavement markings and signage.
	Drivers making left hand turns need to get in the left hand lane and use turn signal following pavement markings and signage.
	Drivers going straight ahead can use either lane.
	Missed your exit? No problem. Just circle around the roundabout again.

Now let’s practice driving modern roundabouts ~ ready, set, go!

	Choosing the proper lane.
	Yield to pedestrians.
	What to do when encountering emergency vehicles.
	Using the truck apron for large vehicles.
	Improper lane change results in crash.
	Wrong assumption leads to crash.


SPIRAL STRIPES MAKE DRIVING A MODERN ROUNDABOUT EASIER
For the driver’s ease of entry, spiral striping is used when a modern roundabout has one or more entries that have dual left turns.
	This visual guide enables a vehicle that enters the roundabout prior to the entry with the dual lefts to be "spiraled" from the inside lane to the outside lane without having to cross over lane lines. Spiral striping prevents a vehicle in the interior lane from being trapped by the dual left turning vehicle in the outside lane. Spiral striping also prevents vehicles from making unsafe exits from the wrong lane.

“HIKING AND BIKING” A MODERN ROUNDABOUT

Modern roundabouts are generally quite safe for pedestrians. First of all, pedestrians cross only one direction of traffic at a time. Crossing distances are relatively short and traffic speeds -- 15-25 mph.

Studies in Europe indicate that, on average, modern roundabouts can reduce pedestrian crashes by approximately 75 percent. Other studies also report reductions in bicycle crashes.

Because vehicles are traveling at low speeds -- comparable to those of a bicycle -- bicyclists can choose to negotiate a modern roundabout like cars.

YOU NEVER MERGE . . . ALL TRAFFIC APPROOACHING A ROUNDABOUT MUST YIELD.

	Enter into a traffic lane before bike lane ends.
	Ride close to the lane’s middle to prevent vehicles from passing and cutting the bicyclist off.
	Enter the roundabout after yielding to vehicles already circulating.
	Circulate being careful to watch for vehicles waiting to enter.
	Exit the roundabout as a car does.

Of course, if a bicyclist just wants to cross to the other side, they can “walk” their bike and use the crossroads as a pedestrian.


MAKING ROOM FOR LARGE VEHICLES
	Using the truck apron for large vehicles.

Do not try to pass large vehicles such as trucks, buses, vehicles pulling boats, sport utility vehicles, horse trailers, tractor trailers or oversize motor homes in a modern roundabout!

Fire trucks and ambulances have the right of way. Motorists should exit or pull over.

Modern roundabouts accommodate larger vehicles with an area between the circulatory roadway and the central island. Known as a truck apron, this area is designed to safely accommodate the rear wheels of these vehicles.

The truck apron is generally paved with brick or cobble stones to physically separate it from the roundabout’s circulatory roadway and to discourage use by smaller vehicles.