Tuesday, March 25, 2008

Traffic calming island or "gotcha" device?

"Traffic calming island" is such a soothing word. It evokes a philosophy of thoughtful traffic engineering saving careless drivers from themselves by gently restricting their options in such a way that they can't get into trouble and hurt themselves or others.

The real world is different. All too often these devices seem designed less to calm traffic and keep drivers out of trouble than to punish drivers when they do get into trouble by making their situation even more dire and dangerous. It's like using "gotcha" as a principle of traffic engineering. Sometimes there's even a possibility of innocent bystanders being hurt during the "gotcha" moment.

This is an example that particularly bugs me, perhaps because I drive by it so often. This island is asymmetrical, with more than half jutting out into the southbound lane of Glenway Street on the near west side of Madison. To really get a sense of what's happening here, you need to know that Glenway runs downhill from Mineral Point Road to Monroe Street. Most of it is a straight, unobstructed run down a gradual slope alongside Glenway Golf Course, lulling many drivers into exceeding the 25mph speed limit. The average speed seems to be about 35 mph, and the occasional driver goes much faster, since there's often not much traffic.

Aside from the usual problems of speeding in a residential area, there's another hazard lurking up ahead for the southbound driver. The roadway suddenly turns into a steep, winding plunge down to Monroe Street, including a tight decreasing-radius downhill turn. There's also a bicycle/pedestrian crossing, followed by another marked pedestrian crossing right after that turn. The marked speed limit is 15 mph, for good reason. The problem is getting drivers to pay attention to it.

I sympathize with the objective, but this seems an odd way to go about it. This island comes right after that tight turn. Drivers who go into it too fast will be fighting for control all the way around the turn, and then, just before the pedestrian crosswalk, they will have to suddenly veer around this slightly elevated obstacle -- or run over it, which also could add to their control problems, especially when there's snow or ice on the road. Whenever I pass this combination of traffic island and pedestrian crossing in the winter, I imagine a speeding car encountering this obstacle, trying to swerve around it, and skidding right into a pedestrian standing at the edge of the crosswalk. That really would be a "gotcha."

This isn't a problem for locals who frequently drive this way and are used to slowing down. But this traffic calming island isn't really for them in the first place. For drivers who need to slow down, it's too little, too late, and potentially hazardous as well -- in other words, more about driver punishment than traffic calming.


John Martin said...

On Reetz (behind West Side Home Depot), they have a few of these islands, and I'm terrified to jog or walk my dog past them. Why am I walking on the road anyway? For some reason, there are no sidewalks on Reetz, so there is no other place to walk but on the road (or across people's yards).

The "traffic calming" islands force drivers to stick to the outer edges of the street where pedestrians hang out. On a "non-calmed" street drivers can cross into the other lane to avoid pedestrians, but on "calmed" streets, they have to squeeze between the pedestrians and the calming islands.

Of course in the winter the islands are twice as wide, and streets are narrower because the plows can't get all the way to the curb. In summer the islands are a bad idea. In winter, they're criminally dangerous.

Clair of Libertarian Logic said...

There are only a handful of calming islands in Cheyenne. They're the idea of our former City Engineer that tells me, "No one likes them, but they work." Oh really, isn't something that works supposed to be supported instead of reviled?

I have a few beefs with "calming islands" here in Cheyenne. First, they were installed to slow down traffic that travels through a curving street where city council members and other VIPs reside. The islands are on the outside of the lanes between the traffic and bike lane, and that makes entering and exiting the street difficult and hazardous because it requires drivers to swing wide to avoid the obstructions. For safety purposes, I sound my horn vigorously as I drive down that street. It's also my way of saying thanks to the politically connected.

Second, calming islands waste part of the right-of-way that public funds paid for. The street I'm speaking of is a very generous right of way, only half of which is used by traffic because of these man made obstructions.

Third, drivers in the winter will often steer well clear of them, even if it means crossing over into oncoming traffic, so I avoid this street when snow is on the ground, unless of course I need to blow snow out of my car horn.

Fourth, the markers for these oblong islands are positioned well in from the edge of the islands so drivers aren't informed of the location of these curbs in the road. This is a hazard in low light and low visibility conditions like rain, fog and snow.

Roads are one of the wonderful things that government accomplishes with reasonably good results, and calming islands are their way of designating the project with a distinctive government pedigree.

Clair Schwan

Anonymous said...

A competent traffic engineer would never put in a traffic calmer without altering the painted double yellow line. In this picture, a vehicle using the yellow line for guidance is directed right into the calmer. The yellow lines need to gradually split so that they go to the outside of calmer.

Anonymous said...

Yeah, this was clearly the half-a**'d work of someone who didn't know what they were doing. These kinds of calming devices can be done well.