Learning Curve

I don’t know what the hell a “traffic calming circle” is and whether it varies from a modern roundabout, but I was needless to say intrigued by this tale.

“Please listen to us”…[said] one of several people to speak against the circle Tuesday. “It’s unsafe and definitely against our wishes. We do not want the calming circle and we don’t understand why you want it for another day. Take it out!”

Yes, killer traffic calming circles! Run for the hills!

What exactly are they doing, these vicious facilities? Terrorizing local children and small dogs? Raising the number of collisions?

But city traffic engineer Maria Esther Rodriguez said the circle has worked to reduce speed. Studies show the average speed on Holm has dropped from 37 to 30 mph since the installation, she said.

Residents wanted something else instead.

The council was skeptical of the circles from the beginning, approving the project on a 4-3 vote in April. Foes favored four-way stops, but staff said they lead to more traffic congestion.

Engineers know, of course, from experience that stop signs are not a speed control mechanism.

In the meantime, the city is investigating using the sign above to ensure speed compliance. Just kidding.

This entry was posted on Thursday, August 27th, 2009 at 3:24 pm and is filed under Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

5 Responses to “Learning Curve”

  1. Kevin Love Says:

    Four-way stops are also cyclist harassment devices, resulting in significant increase in effort due to starting and stopping. Which is why you won’t find them in The Netherlands. And why Toronto is looking at replacing many of them with “yield” signs to show right-of-way.

    The most effective speed enforcement is photo radar. 100% of offenders get charged.

  2. Bossi Says:

    Traffic calming circles, per definitions around here, maintain the existing right-of-way controls. So if you have a 4-leg intersection with a 2-way stop on the minor street: you’d have what resembles a roundabout, except the mainline has less deflection & also dominant right-of-way. The minor street continues to be controlled, though its stop signs would likely be replaced by yield signs.

    The issue I have with traffic calming circles is expectancy: in Maryland we have plenty of roundabouts, so putting in a traffic calming circle may result in mainline motorists stopping unexpectedly; or left-turns across the mainline may not know that they are to yield to opposing mainline traffic.

    Here’s a standard from the Virginia DOT:

  3. Crosius Says:

    I have two traffic circles near my house. I have yet to see any driver (other than myself) follow our local traffic codes for using them. People in my community also fail to use 4-way stops and weave-lanes correctly, and short-cut down the wrong side of divided roads to get into the laneways behind their houses, so this isn’t much of a shock. Cycling in my neighbourhood is an exciting hobby.

    I think complaints about road features are more often linked to a “I don’t know how to use it and I don’t want people laughing at me when I use it incorrectly” thought process than any other reason. Drivers don’t want to look stupid (but they also don’t want to look up the relevant traffic code, either). That level of laziness and ignorance behind the wheel of a car is a frightening prospect.

  4. aaron Says:

    Is slowing traffic a good idea?

  5. Kevin Love Says:

    Aaron asked:
    “Is slowing traffic a good idea?”

    Kevin’s answer:
    It depends. A lot of bicycle traffic needs to be speeded up by doing things like eliminating four-way stops. Bicycle traffic should be going at 20-30 km/hr. At the same time, a lot of car traffic needs to be slowed down so that it is also going at 20-30 km/hr.

    It is safest when everyone is going at about the same speed. Also, cars going less than 30 km/hr kill a lot less people when they hit them.

    This is why I advocate 30 km/hr car speed limits strictly enforced with photo-radar and fines high enough to pose a strong deterrent.

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Traffic Tom Vanderbilt

How We Drive is the companion blog to Tom Vanderbilt’s New York Times bestselling book, Traffic: Why We Drive the Way We Do (and What It Says About Us), published by Alfred A. Knopf in the U.S. and Canada, Penguin in the U.K, and in languages other than English by a number of other fine publishers worldwide.

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Metropolis and Mobile Life
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