Journal fiannaFailMan's Journal: Why roundabouts are better intersections 28
Interesctions in the US, especially in California, are of the four-way type. You either have a four-way stop, or a four-way traffic-light junction. These are both inefficient and they are death-traps. Why?
Let's start with the inefficiency. At larger suburban intersections the cycles on the lights are very long. If you stop just as a light turns red and you're waiting for the left arrow, you can be sitting there for a good few minutes. Traffic is going to back up behind you. This can create problems further back at the previous junction, so to avoid it, what do we do? We build extra lanes, not to accomodate all that moving traffic, but to store stationery vehicles stuck at the lights. This contributes to the horrors of sprawl as well as being a monumental waste of resources.
From the motorist's point of view, it turns his journey into one big stop-and-go session. No wonder automatic gearboxes are so popular in America, the amount of stop-n-go driving is unreal! And regardless of whether your transmission is automatic or manual, stop-n-go driving is not good for your engine, fuel consumption, or the environment.
Now let's take the safety issue. How does a 4-way stop-light encourage you to drive? That's right, it gives you an incentive to speed through it at the most dangerous time, i.e. when the light has just turned amber. I read that a third of all crashes happen at intersections. This is not one bit surprising.
Then you have the four-way-stop. These are fine, but what happens when you come to a stop sign where the cross-traffic does not stop, but there's no sign saying so? Someone approaches the stop sign, stops, sees a car coming from the side, assumes that he has right of way, moves off, *BANG!*
So. What are the alternatives? One word. Roundabouts.
Anyone who has been to Europe will have seen them because they're everywhere. For the uninitiated, these are 'yield-at-entry' traffic circles. As you approach the roundabout, you slow down as it flairs off to the right (in a country where you drive on the right) and you approach a yield sign. If nothing is coming around the roundabout towards you, you drive on. If something is coming around the circle, you yield to him. In fact, you don't have to stop, it's better if you slow down and just fit yourself into any gap that comes around. Once on the circle, you drive anti-clockwise without stopping because everyone else approaching the roundabout now has to yield to you and you keep on going until you're off the roundabout and on your merry way.
It works on the principle that it's unlikely that a large number of vehicles are going to be going to be going in the same direction, so you never have to wait very long for a gap to open up. If a car is coming around but shoots off the roundabout into the exit before yours, that buys enough time for you to drive on.
Advantages? Well for one thing the traffic overall flows a lot better. You seldom have to stop, so there's no need for big wide roads to store stationery vehicles. They are also safer than 4-ways believe it or not. Studies show a reduction in the number of accidents where 4-ways are replaced by roundabouts. Reason? Well instead of giving the motorist an incentive to speed through to make the light, one is forced to slow down because of the curvature of the thing. Also, there are fewer points where a collision can occur. On a 4-way there are over 30 potential collision points, twice as many as on a roundabout.
Disadvantages? Bigger roundabouts can be difficult for cyclists to navigate. Also, because traffic flows more or less continuously, they are not suitable for urban centres where large numbers of pedestrians need to be able to cross the street. Lack of familiarity when they are first introduced would be a problem, but one that is easily overcome with public education campaigns.
Listen... (Score:1, Flamebait)
I'm sure you're right, but you can't expect me to read that whole thing, right? I mean, I'm an American, so, like all Americans, if given the choice of having something done right or done fast, I'll choose fast.
Stupid Americans. We're so stupid.
New Jersey has circles (Score:2, Interesting)
First rule of driving thru a circle: he who hesitates is lost. Look like you aren't going to stop, and merge in. While you're in the circle, look like you're going to cut off anyone entering your path. Note: it helps to have an older American 4-door; previous rust is a plus, dents are better.
Roundabouts can be useful, but multi-lane roundabouts can border on the insane, especially when traffic *entering* the roundabout has the right of way.
Re:New Jersey has circles (Score:2)
1) Get in a lane and stay in it - don't drift around.
2) Consider a 4-exit roundabout (they can be 3-6 or even more but 4 is most common). If you are getting off at the first exit stay in the outer lane. If you are going straight across pick the middle lane (if there are 3) or inner lane (if the
Re:New Jersey has circles (Score:2)
A translation for the Ill-Briterate: "Use your turn-signals i.e.: 'indicators'".
Yes, this means you Mr. Born-and-Bred-in-Los-Angeles.
This was wonderful! You stopped, just as I hoped it might go on aways.
The Magic Roundabout (Score:1)
Re:The Magic Roundabout (Score:2)
Total agreement, however..... (Score:1)
Re:Total agreement, however..... (Score:2)
Re:Total agreement, however..... (Score:2)
Pennsylvania (at least an area to the North West of Pittsburgh) started installing smart traffic lights that changed based on vehicle detection. The lights didn't exactl
breakin the law!!! (Score:2)
Showing up in Utah (Score:2)
Ever been to Brasilia? You'd like it. (Score:2)
Re:Ever been to Brasilia? You'd like it. (Score:2)
Re:Ever been to Brasilia? You'd like it. (Score:2)
The real problem is that the city was designed for about 2 or 3 million people, and there's somewhere between 0.5 and 1 million actually living there, so the population is rather spread out. There's just nothing to dr
Mod parent up (Score:1, Flamebait)
Yes, roundabouts are better, except for two cases (Score:1)
The picture at http://www.paris.org/Curiosites/Etoile/etoile.jpg [paris.org] should explain it all.
2) Signal controlled roundabouts. The Mad^WRed Cow Roundabout[1] on the M50 in Dublin (the one in Ireland (for the non-Irish here)) and the M50 interchange at Blanchardstown (also Dublin) are prime examples of how signal controlled roundabouts can go horribly wron
Re:Yes, roundabouts are better, except for two cas (Score:2)
It's a good question. Sometimes it's necessary during high-volume commuting hours. As I said in the journal, the idea is that it's unlikely that a large number of consecutive vehicles are going to be going in the same direction. However there are cases when this does happen, like when a lesser-used road [1] feeds onto a roundabout that also gets
New Jersey (Score:2)
in the north east (Score:2)
Cyclist attitudes on roundabouts (Score:1)
I don't know their exact rationale, but personally, I've found roundabouts pretty easy to negotiate. (Of course, I am accustomed to riding my bike in a vehicular manner [tomswenson.com], as though I were riding a small, slowish car.) Well, in my new incarnation as a New York City bikie, going around Grand Army Plaza in Brooklyn had me looking over my shoulder a bu
Re:Cyclist attitudes on roundabouts (Score:2)
Not a bad idea, but it still needs some work. (Score:1)
See, I know being on a college campus does not help given how stupid the drivers usually are, but anyway... the problem was that this roundabout was placed at a 4-way intersection, though the majority of the peo
Re:Not a bad idea, but it still needs some work. (Score:2)
In the example you have cited, that is one example where roundabouts are maybe inappropriate as I explained somewhere else. But I have my doubts that there would be an increase in accidents. There are studies [langford.bc.ca] that show that roundabouts actually reduce the number of accidents. Yes there may be a few prangs because of people being confused, but this is insignificant compared to the number of crashes ina fo
Re:Not a bad idea, but it still needs some work. (Score:1)
Another problem that this partic