Advocacy & Safety - Part 4 - Traffic Circles.

Traffic circles can be quite daunting for cyclists, because there are so many vehicules (including cyclists) crossing paths, that it is a recipe for disaster. The general rule for traffic circles is that you must give priority to people already inside. There are a couple exceptions to this, namely the Arc de Triumph in Paris and a few others around Paris. Where they work in the opposite manner, people entering have priority. There are two cases to consider.

First : The traffic circle with one lane entrance into the circle. The safest course of action is to take the lane and enter as an automobile. Maintain the lane through the circle and exit at the desired destination. If making a right hand turn from the circle (or left for those brits and auzzies) taking the lane isn't necesiary because you are following the curb.

Second : In a multilane entrance (2 lanes, I would probably avoid any traffic circle that has 3 lane entry becaue of the sheer volume of traffic) taking the lane again is a possiblity. Take the lane depending on destination. Merge Left to go strait ahead or make a right hand left turn.

Some traffic engineers have wanted to put bikeways on the periphery of the traffic circles and then either controlling the entrances and exits with lights or having the cyclists yeild completely to cars. In either case, the result is not desireable. Primarily because it forces either more delays for everybody (or atleast the cyclists) and furthermore, it creates more opporunities for car-bike collisions because the cyclist must cross the roadway more times than if he simply acted as an automobile.

Perhaps the only bicycle-friendly traffic circle is a tight-radius, 15mph structure, with a big "bicyclists taking lane" warning sign on each approach. Three are proposed for my immediate neighborhood, to replace one four-way stop and two two-way stops. Stay tuned ...

Generally speaking I try to take the lane and act like a motor vehicle in these situations. It's rare that I'm not doing the same speed as the cars on roundabouts/traffic circles, so it's probably the best option.

I try and take the lane as well, although I got hooted at this morning for having the cheek to asert my right to do so (on a single lane roundabout too!) Apparently I wasn't indicating!

Well, that's what the woman shouted out of the window as she overtook and cut me up whilst I was on the roundabout. Er, I was going straight over, you don't indicate to go straight.

Silly %!#@

Anyhow, If I hadn't taken the lane she'd of cut me up at the entrance to it anyway. Most motorists are fine it's just this minority who think they know it all, when in reality they are the ones who are wrong. Sorry, I'm starting to rant :)

I always take the lane and I'm very careful to look for vehicles cutting me up on entances and exits.

Richard

Modern roundabouts are virtually non-existant around here. That's true most places in the US. Almost all the responses to this thread have been from people in the UK or Australia, the two places that developed the modern roundabout.

There was one reply from California:

Originally posted by John E
Three are proposed for my immediate neighborhood ...
Yea, exactly: "proposed"
That's about the state of modern roundabout development in most of the US. :D

I know of one in the St. Louis area that was just completed this year. And another that was built a couple of years ago and removed within a year because of citizen complaints. There is one in Columbia, MO (120 miles away), and it's such a rarity that pictures of it are on several road geek websites.

And then there's Avon, CO, which calls itself the Roundabout Capitol of the Rocky Mountains (http://www.avon.org/round.cfm) - I think Avon has a grand total of 5 roundabouts, but that's more than most states have. I have seen pictures of some in NY and California - those states probably have more than 5 each. ;) Because of it's roundabouts, Avon is famous.

They stopped building traffic circles in the US in the 1950s. The first modern roundabout built in the US was in 1991. They've been building them in the UK and Australia since the 1960s.

A number have been built in the US in recent years but there's a good deal of opposition to them, and they're still as rare as a 3 dollar bill in most places.

We do have a few traffic circles. I usually take the lane. I have no experience riding a bicycle through a modern roundabout.

From what I've read, modern roundabouts reduce the rate of accidents for all vehicles except bicycles. Many of the accidents involve cyclists who don't take the lane.

Originally posted by JRA
That's about the state of modern roundabout development in most of the US. :D

I know of one in the St. Louis area that was just completed this year. And another that was built a couple of years ago and removed within a year because of citizen complaints.

Both in Chesterfield, where I live. The one that was removed was, essentially, on my street, though about 2 miles away. It was part of a traffic calming project that included removal of most stop signs and installation of speed humps and medians which consisted of asphalt curbing enclosing suffering trees in giant concrete flowerpots. The medians made traffic lanes wide enough for one vehicle only--no room for bicycles and cars next to each other. The speed humps (very wide speed bumps) were to slow traffic down, and they worked well, but officials of the fire district supposedly complained they also slowed down emergency vehicles. The roundabout was at an intersection of two primary subdivision streets. It replaced stop signs that caused traffic backups at the intersection during rush hour. I thought it worked well.

Another roundabout near here controls traffic entering and exiting a limited access section of Highway 141 from and to Woods Mill Road. It is a single-lane circle. I have cycled and driven through it and find it works well. Traffic leaving the highway moves more efficently onto Woods Mill, and traffic driving through the circle along Woods Mill moves slowly through the circle. Cyclists pretty much have to take the lane through the circle, but the circle is tight enough and small enough that drivers really don't have much opportunity to pass until both are out of the circle. There is enough room that a car can pass a bicycle that stays all the way to the right.

Public works officials in Chesterfield and Ballwin, two municipalities in the St. Louis area, have been talking up roundabouts for years. Ones that are designed well ought to be safer for drivers and cyclists, at least single-lane ones. I have little experience with multi-lane roundabouts.

Originally posted by Prosody
Both in Chesterfield,...
Yea, Chesterfield, St. Louis County. (I'm not actually in St. Louis proper, either) ;)

About the roundabout that was removed:

I thought it worked well.I wondered about that. Evidently somebody else didn't think so. It was some kind of experiment I guess.

The medians made traffic lanes wide enough for one vehicle only--no room for bicycles and cars next to each other.I don't think I care for that kind of traffic calming (narrow lanes). But I like what I read about roundabouts.

Another roundabout near here controls traffic entering and exiting a limited access section of Highway 141 from and to Woods Mill Road. It is a single-lane circle. I have cycled and driven through it and find it works well.I'm glad to hear it works well. I haven't actually seen it although I remember how Woods Mill used to be in that area (I haven't driven that section of Woods Mill recently)

I have little experience with multi-lane roundabouts.
Apparently, there's a multi-lane roundabout planned near you - at the intersection of Clayton and Kehrs Mill, which is in Ballwin.

Intersection: Clayton Rd/Kehrs Mill Rd
# of Approaches: 4
Type: Multi-Lane
Construction: New
Previous Traffic Control: Signal
Date of Completion: 2004

That still won't make many roundabouts in the St. Louis metro area. (We're not counting the infamous Halls Ferry traffic circle, which couldn't be considered a modern roundabout by any stretch of the immagination. ;))

MoDOT's long-range plans call for rebuilding 141 (to 6 lanes) from Ladue Rd. to Olive St. Rd., with a two-lane roundabout west of a new interchange at Ladue Road. Don't hold your breath. ;)

They give me the willies, doesn't matter what mode of transportation. There's just too much going on in too many places all at once. The best (actually worst) example I can think of is one somewhere in downtown Washington DC. There may be many... I just remember doing 3 or 4 laps at this one, one night. Two lanes with I-have-no-idea how many entering-exiting side streets. A bazillion traffic signs situated such that you don't know WTF lane or side street they apply to, but h#ll, you're too busy trying to keep you fender clear of that taxi driver to worry about it anyway! :fun: