It is the French as reported in The Economist that in the early 1900’s came out with the carrefour giratoire, the precursor to the modern traffic circle. When installed in Paris, traffic circles require circulating traffic in the traffic circle to give way or priority to car traffic coming from the right.
If you have driven in France in the last ten years, you will have seen a proliferation of traffic circles, with estimates of 30,000 existing and a further 500 annually installed. Why? Because of road safety. The graph below shows the USA with the greatest number of road fatalities and the smallest amount of roundabouts.
As the Economist article states, In America, for instance, which has a mere 4,800 roundabouts, a quarter of all road deaths take place at intersections. America’s Federal Highway Administration, which helpfully supplies a “roundabouts outreach and education toolbox” to overcome public distrust, says that they reduce deaths or serious injuries by around 80%, compared with stop signs or traffic lights”
There are some challenges with traffic circles, especially in the safe and efficient design for pedestrians to cross at well delineated places. Traffic circles also require a lot of land when there are two or three lanes of traffic in the circle. They do however lend themselves to great art installations and plantings, and these have multiplied in France with the rise of local authority spending. In addition, the traffic circle has become worthy of architectural analysis:
“The roundabout has accompanied the development of the fluid society,” suggests Laurent Devisme, of the National Architecture School in Nantes. Like modern life, it requires “judgment, anticipation and commitment”.
Perhaps the traffic circle is one of the last hurrahs of motordom, celebrated as a place people go through and to but never linger in. Could improved intersection design, greater visibility, and slower vehicular speeds accomplish the same and allow for better walkability and livability?
um, isn’t this kinda an apples to oranges graphic? Traffic circles per 1000 intersections vs overall road fatalities (not necessarily at intersections) … the traffic circle isn’t doing much to affect the behavior of traffic anywhere other than in itself … so a place with a high intersection/road ratio would fare ‘worse’ than a low intersection/road ratio when measured with this metric.
Traffic circles are safer in that they tend to lessen the severity of a collision. Cars still run into each other, but the reduced speeds and deflection angles through the circle mean fewer cripples and corpses compared to normal intersections.
There are a whole bunch of factors relating to the road fatalities. It’s an interesting relationship that the figure above shows and worthy of a hypothesis, but just showing it doesn’t “prove” roundabouts are the cause of fewer road deaths per capita.
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Reblogged this on Sandy James Planner.
While larger roundabouts have shown benefits in injury reduction for motorists, that is not true for all transportation modes and all roundabout designs. A study that looked at Toronto’s and Vancouver’s traffic circles (small roundabouts on local streets) found an increased risk of injury for cyclists. From the article, and referring specifically to cyclists: “Traffic circles were more hazardous than all other intersection types (traffic lights, two-way stops, four-way stops and uncontrolled intersections)” Full details at:
http://injuryprevention.bmj.com/content/early/2013/02/13/injuryprev-2012-040561.full.pdf+html
Note that the City installed a traffic circle on the 10th Ave bikeway at Pine, and after crashes increased, later removed it.
A cycling assessment ride along the 10th Ave Bikeway noted observations of significant differences in visibility of oncoming traffic depending on whether the centre of the traffic circle had low ground cover shrubs, or vertical plantings/trees/signs/art that obstructed the vision of people approaching the traffic circle. At some traffic circles along 10th Ave the “keep right” signs are elevated on posts, at others they have been lowered to just above the curb.
I’m not a fan of those miniature neighbourhood traffic circles. Sure they can be dressed up with plants to look pretty, but they’re terrible for small road users (anything smaller than a Smart car).
1. Drivers don’t signal so it’s impossible to predict which of the 4 (yes people use them for U-turns) exits they’re likely to take.
2. Drivers almost never slow down unless they see impending disaster.
3. The signs and pretty foliage in the middle obscure the view of the far side. Children can be completely invisible to drivers and cyclists.
4. Drivers usually look left as they approach the circle and then to the right. By the time they’re looking in front of them again, they’re often only a few metres from the far crosswalk, not nearly enough space in which to stop.
5. Cyclists usually cruise through at full speed under the mistaken belief that they have the right of way and that pedestrians and approaching cars will stop for them. In reality they’re rarely noticed until it’s too late.
6. Just because one driver or cyclist stops doesn’t mean the others even slow down unless that stoppage is blocking their progress. Stopping in a traffic circle seems to be viewed as a sign of indecision and unfamiliarity, not one of traffic safety or courtesy.
There’s a circle on the way to the kids’ school. I’ve lost count of the number of times drivers have seen us standing at the crosswalk and zipped around the circle or made a right turn directly in front of us without even slowing down. It’s reached the point where I won’t step off the curb if there’s a vehicle of any kind within 50m of the intersection unless the operator clearly slows down and signals us to go ahead. It’s one of the reasons why I almost always walk to the school along a different street with normal intersections. The nearest designated cycling route also has a traffic circle. When practical I choose an alternate route to avoid having to cycle through the circle.
I agree. I am sure that many people do not know the rules re traffic circles. I have memorized the rules but am still unsure what to do. Different descriptions of the rules appear to be contradictory. Here is one provided by ICBC:
“Yield to any traffic in the traffic circle. If another vehicle arrives at the same time as you do, yield to the vehicle on your right.”
I find this way too complicated. Why not use the roundabout rule where one always yields to the vehicle on the left? To make matters worse, different municipalities use different rules and in New Westminster there are three traffic circles in a row on 7th Ave and two are marked with 4 way yields and one has no signs except to keep right to go around the circle. It might help if we had consistent rules for all roundabouts and traffic circles.
I don’t see an online archive at the Vancouver Courier, and even if there was one it might not go back to 1991 or 92 when what I think was the first traffic circle in Vancouver showed up. It was installed at the point where 8th and 9th Avenues meet (if I recall correctly, at Wallace) on the hill to UBC. When I first encountered it while riding, I was aghast but at least I stayed upright; there were already indicators that some cyclists had first encountered it in mid-descent, perhaps in the dark, and come away well the worse for wear. Even drivers had apparently hit it. The danger to cyclists was obvious, and the fact that the car path directly intersected with the pedestrian route struck me as idiotic. I contacted the Courier, they did a story, and the traffic circle disappeared not long after.
As a result, perhaps, of that first encounter, I have never come to terms with them, especially since no effort has ever been made to instruct drivers who got their licenses in pre-circle days how to properly use them. And the pedestrian thing has never been solved. Truly, to become in any way reconciled to them, I would have to see statistics on in-intersection accidents, both frequency and severity.
It’s worth remembering, mind you, that when that first one showed up, most side street intersections in Vancouver were not governed by stop signs, as they almost all now are if they don’t have circles, but by yielding to traffic on the right. So perhaps the relevant numbers would compare accidents in uncontrolled intersections in those days to accidents in side street traffic circles today.
I’ve always loved driving around the Arc de Triomphe. The Piazza Venezia in Rome brings back many memories too, the adrenaline pumping! You just have to launch yourself into these wonderful spinning phantasmagoria and test your mettle.
The above comment will naturally shock some. Be assured though that alert drivers are far safer than those just ambling along in a semi-stupor.
It’s those things we have when we don’t have roundabouts…What are those called where roads intersect? I can’t put my finger on it.