POLL: Do Roundabouts Support Traffic Safety?

Nancy Hall August 20, 2012 at 07:48 pm

I just returned from a week in New England...mostly Maine. I encountered a couple of roundabouts (or rotaries as they're called in NE) in Augusta that weren't bad, although the signage was strange. Each route number was accompanied by a diagram showing which lane to use and the pattern of travel. These little squiggles were way too complex for somebody approaching the rotary for the first time and attempting to travel through with traffic.
I also had to do some Boston driving. I drove through a couple of rotaries including one, the Bell Rotary near Logan, that was bisected by a road that went straight through. This one had traffic lights, thereby defeating the original purpose of the rotary. They stopped the rotary traffic so people on the straight road could drive through. It really defied logic. I've done a lot of Boston driving. The rotaries there are treacherous. Some of the most dangerous intersections in Boston involve rotaries. There may be advantages to controlling intersections with rotaries, but safety is not among them.

ScottRAB August 20, 2012 at 08:46 pm

Here’s a quote:
“By 2025, a quarter of all drivers in the United States will be over the age of 65. Intersections are the single most dangerous traffic environment for drivers of any age with left-hand turns being the single most dangerous traffic maneuver that any of us can make. Forty percent of all crashes that involve drivers over the age of 65 occur at intersections. This is nearly twice the rate of experienced younger drivers. AARP would like to see more roundabouts constructed because of the many safety benefits that they present for drivers of all ages.” - Jana Lynott, AARP Public Policy Institute

ScottRAB August 20, 2012 at 08:48 pm

I'm pretty sure most state laws direct motorists to not drive beside semis in modern roundabouts.

ScottRAB August 20, 2012 at 08:50 pm

Modern roundabouts are designed for trucks by including the center flat area around the circle. It’s not a sidewalk, it’s called a truck apron, and it’s for trucks to begin a sharp right or end a left or U-turn on. Visit http://www.youtube.com/watch?v=vsCoI7lERGE
Or http://www.youtube.com/watch?v=0nVzsC2fOQw for examples.

Cliffside August 20, 2012 at 08:50 pm

so they want to put a roundabout in at 31 +32, however if you take those two intersections and the roudabout on K the last fatal accident was on K!

ScottRAB August 20, 2012 at 08:51 pm

Modern roundabouts are the safest form of intersection in the world. Search IIHS for FAQs and safety facts.
NCHRP 572 was the most recent evaluation report.

ScottRAB August 20, 2012 at 08:54 pm

Total crashes is a misleading number. Crash rate only gets at half the issue also. Crash rate compares number of crashes to number of entering vehicles and is expresses as crashes per million entering vehicles. A value more than 1.00 is usually looked into further. Crash severity is most important. fender benders versus injury or fatals.

ScottRAB August 20, 2012 at 08:55 pm

you're confusing rotaries and traffic circles with modern roundabouts. The first modern roundabout in the US was built in 1990 in Nevada.

ScottRAB August 20, 2012 at 08:55 pm

Many people confuse older styles of circular intersections with modern roundabouts. East coast rotaries are not modern roundabouts. Large multi-lane traffic circles (Arc D’Triumph) are not modern roundabouts. European Vacation was not a modern roundabout. New Jersey/Europe are not removing modern roundabouts. Visit www.k-state.edu to see the differences. www.fhwa.dot.gov has a video about modern roundabouts that is mostly accurate (http://www.youtube.com/watch?v=uhHzly_6lWM ).

ScottRAB August 20, 2012 at 08:56 pm

The first cost of any two choices is a poor way to compare. Life-cycle cost is the best (present value of future costs, a.k.a. net present value). When comparing modern roundabouts to signals for a 20-year life cycle (the standard period), modern roundabouts usually cost us much less. Costs to compare include: first cost (design/land/construction), operation and maintenance (electricity, re-striping, etc.), crash reduction, daily delay (what’s your time worth?), daily fuel consumption, pollution (generated), area insurance rates (this costs more where it is less safe to drive). Each of these things, and others, can be estimated for any two choices and everyone near or using the project area will pay some portion of all of these costs.
More info: http://tinyurl.com/739pu3d

ScottRAB August 20, 2012 at 08:57 pm

The safety of a pedestrian crossing any road, regardless of the intersection control, can be enhanced in many different ways. Signing and marking the crossing is usually the first step. Shortening the crossing distance is another. The safest shortening method is a median that permits pedestrians to cross one direction of traffic at a time (two-phase). This is particularly helpful for the youngest and oldest pedestrians. Enhanced markings include advance stop bars where any half of the crossing has more than one lane. This helps reduce the double-threat collisions. Raised crossings slow traffic right were pedestrians cross. If emergency access is a concern, placement of speed cushions in advance of the crossing are a solution. Electronic warnings, like rapid flash beacons, increase motorists’ awareness of pedestrian activity. Hybrid beacons (with a red indication) or full signals are usually reserved for locations with the busiest traffic or pedestrian uses (due to cost). One advantage of beacons is they usually rest in off, so auto traffic is only delayed when pedestrians need the extra help crossing. With a menu of ways to improve crossing safety, choosing the best one depends on local conditions. However, each of these options is moot if there are not laws in place, or enforced, to clearly identify who has the right of way to begin with.

ScottRAB August 20, 2012 at 08:58 pm

US schools with modern roundabouts nearby:
Ladera Ranch Middle/Elementary School, Ladera Ranch, CA Pine Lake Elementary, Issaquah, WA Sunset Elementary, Bellevue, WA Cotton Elementary, San Antonio, TX Skyview Elementary, Clearwater, FL Sunflower Elementary, Lawrence, KS Fruitville Elementary, Venice, FL First Ward Elementary, Charlotte, NC Cherokee Elementary, Cincinnati, OH Truscott Elementary, Loveland, CO

ScottRAB August 20, 2012 at 09:01 pm

SB,
You'll have to do better than express fear to sway me. You're talking about crossing any road, but putting the roundabout label on your fear. Modern roundabouts have medians so pedestrians only have to focus on one direction at a time. This is of great benefit to our youngest and oldest pedestrians.

ScottRAB August 20, 2012 at 09:03 pm

While it depends on the time of day and how heavy traffic is, in the few locations I've had counted, the stopping rate is 20%-40%. Sounds more like an all-way yield to me.

ScottRAB August 20, 2012 at 09:05 pm

Modern roundabouts or traffic cirlces? name an intersection so we can check. Know what you're talking about before you speak.

ScottRAB August 20, 2012 at 09:08 pm

Modern Roundabouts have only four rules: 1. Slow down, 2. Yield to pedestrians, 3. yield to drivers already in the circular roadway, 4. signal your exit (keeps things moving). Signaling left until you’re ready to exit might help some motorists not jump in front. At a multi-lane modern roundabout, like any other multi-lane intersection, motorists should watch for the lane use signs that tell you which lane to be in based on where you want to go. Like other complex intersections, sometimes only the left lane can turn left, sometimes it can turn left and go through, and some times it can go left, through or right. A lot simpler than signals and modern roundabouts work the same even when the power is out.

ScottRAB August 20, 2012 at 09:12 pm

Modern roundabouts are not rotaries.

$$andSense August 21, 2012 at 02:45 am

You are funny. As a lawyer you should love the lawsuits they could generate. And you can also blame President Lincoln for the racial issues of today. Twit.

Bren August 21, 2012 at 02:52 am

Steve the Job Creator, I hope you will recall that our freeway system is the result of Eisenhower viewing the Autobahn. Our system is flawed because the Germans tested and understood driver fatigue and designed some driving environment shifts (curves, etc.) to ensure alertness. So if you and your employees drive on the freeway, don't forget to thank a European! ; )

Bren August 21, 2012 at 03:13 am

I used to live just outside of DC and drove in the city a lot. The problems encountered had less to do with roundabouts and more to do with tourists getting underfoot (so to speak).

Terryann Longo August 21, 2012 at 03:49 am

I believe modern roundabouts are safer once you get used to them :') At least someone is not going to hit you while they are speeding through a yellow light!\

Teri August 21, 2012 at 09:37 am

It really depends. In some cases, they make perfect sense such as the one at North and Barker. That has made a huge positive impact on traffic there, especially in the morning. In other cases, it does nothing for traffic flow. Lastly, there are areas where they create a dangerous and problematic traffic situation such as I43 and Moreland. A thoughtful and reasoned approach is necessary when making the decision to build one.

Lex Parsimoniae August 21, 2012 at 01:14 pm

What local government (as well as Federal gvt.) seems to not understand, is that we ARE NOT Europe. It's not the roundabout, per se, it is the simple fact that any, and every, idiot with $400 in their pocket can (and usually does) have a car (or four). Maybe 10% of the population can handle situations, that are out of the ordinalry, without having to stop and assess what it is they are trying to accomplish. If everyone could handle the simple concept of a roundabout, they would be spectacular...but most Americans can't handle a straight road if it's raining, or snowing, or the sun is too bright. BTW, roundabouts and pedestrian crossings simply cannot coexist...they are the antithesis of each other.

ScottRAB August 21, 2012 at 10:01 pm

Bill,
So you slow down when going through them? Sounds like they're working.

ScottRAB August 21, 2012 at 10:03 pm

So, you like stopping?

T Van Parys August 21, 2012 at 10:39 pm

I love the roundabouts...vastly more efficient than stupid, miss-timed stoplights. They'll run smoother once our slow-witted neighbors get them figured out.

AG August 21, 2012 at 11:00 pm

Born in England so grew up with these roundabouts, like most people say keeps traffic moving and just a side note if you are a tree hugger you should love these with no electricity being used and can even plant a garden in the middle.
Next thing Americans need to understand you use your directional signal when going around these roundabouts. Left directional signal, you show you are going around and the right signal when leaving the roundabout.

B.a. Liberski August 22, 2012 at 04:03 pm

Roundabouts are a bad idea. Horse and buggy days they were pretty in old france, a hundred years ago. Now they waste time, signs like crazy, road paint that is worn off quickly and invisible during the winter. On the plus side they are better than what the DOT did with the Michel interchange. You have to go right to go left, left to go right and if the traffic is snarled you end up in the wrong lane and 20 minutes get added to your commute. Billions wasted. Chicago sucks but it is now better than here. Milwaukee will have road destruction forever, just like Chicago.

Spencer August 23, 2012 at 05:36 pm

If they are about safery at dangerous intersections why are thee three consecutive round abouts just outside Milton one of which is not even an intersection. That's right, just a round about no other road going into it. Even if they build another road leading into it how do they know it's going to be dangerous? As far has traffic flow I've had to stop numerous times at them to allow cars from the left to go by, so the idea that you don't have to stop at them is not really true. Maybe they're worthwhile at some intersections, but I think some communites are going overboard.

Ann August 25, 2012 at 11:57 pm

go to Oshkosh - two on one side of the freeway at 9th avenue and 3 on the other side - try having time to determine what lane you need to be in to get on the freeway