Kirby widening poses dangers
Pedestrian realm to be smaller
A fast-moving project to widen Kirby Drive, remove its trees, and make the pedestrian realm smaller needs some emergency attention from cool heads.
Kirby Drive between the Southwest Freeway and San Felipe is soon to be completely torn up in order to improve the storm sewer system in the area. This is much needed, as there is frequent flooding in the area.
But the construction means there is an opportunity to make the streetscape better, and there has been considerable energy put into that idea over the last few years. Unfortunately, it also means the City's Design Manual comes into play, and those rules say the reconstructed street as to have wider lanes then it does today. In addition, a 14-foot median is proposed.
Together, the effects of the rules in the outmoded Design Manual plus the size of the median mean that 174 trees will have to be cut down and the pedestrian realm on each side will be 7 feet narrower. These are both horrible ideas.
Trees for Houston is all over the tree part and has begun a campaign to prevent it. But so far there's been little interest in what happens to the pedestrian realm and safety in the street.
Let's tackle the widening of the lanes first. The national "Complete Streets" guiding principle is this: "A complete streets policy ensures that the entire right of way is routinely designed and operated to enable safe access for all users." Those users include not only drivers, but pedestrians, bicyclists, and people in wheelchairs.
Given that the pedestrian realm in Houston has been routinely compromised almost everywhere in Houston over the last 50 years, it is imperative to insist that no project should ever again move the curbs outward from the centerline, except when all the adjoining private property moves away at the same rate to retain or improve the pedestrian realm. (That should be true for Metro projects, as well, by the way.) Considering that 40 percent of Houstonians do not drive, and that the City is becoming much denser, the pedestrian realm is not a place to simply steal space from for some imagined increased comfort of drivers.
This is particularly true if the reason to widen the car area is either pointless or even negative. That's the case with the Kirby plan.
The two issues - widening the lanes and adding a median - are quite different. (And by the way, no one is calling for making the lanes narrower, as some elected officials seem to be hearing). Widening travel lanes does not add any capacity at all. It merely suggests to drivers that maybe they can go faster because it feels a little more open. This principle is very well understood in the profession, and modern practice is to actually narrow streets in urban places in order to "calm" traffic. This has the effect of increasing safety for pedestrians and drivers as well.
The only conceivable benefit to widening the lanes is to increase speed, because wider lanes signal to drivers that there is a lower level of care necessary.
Going a little faster means the throughput will be decreased. That is, the number of cars that can get through an area in a given period of time is less at higher speeds. This is because cars space out more at higher speeds, and thus take up more room. The optimum throughput speed is about 30 miles per hour.
In an urban situation like Kirby, going faster is dangerous.
As Dan Burden, one of the great expert practitioners in streetscape design, says, added speeds reduce operational efficiency, reduce safety, and inspire risky driving. Apparently, the Upper Kirby District's engineering study for the street project claims that going faster will increase safety and mobility. I am unaware of any studies that will support that idea, and in fact many studies support the idea that higher speeds are less safe. Certainly, pedestrians hit by cars going 30 mph are likely to be killed (see graph at right, from ITE
). Below that speed, injuries become less serious as speed decreases. Likewise, there is ample evidence of a link between lane width and serious injuries, for the reason stated earlier: people go faster in wider lanes.
Much of that stretch of Kirby is fast becoming more urban and more pedestrian oriented. Enormous projects are under construction right now and more are coming. Kirby between 59 and Westheimer is going to be about walking. Why would any of the developers or tenants want the pedestrian realm to be reduced to suburban size (two people can't walk next to each other)? In addition, it seems likely that wise heads might prevail and we'll soon have a light rail stop at Kirby and Richmond. This is no place to be speeding up traffic as hundreds of new visitors are delivered to the District on foot every day.
No, the widening is a terrible idea with no positive attributes.
The median, on the other hand, is really important. Many studies show that putting a median into a street can reduce crashes by about half. We are cavalier about safety in Houston and that's why we have more serious car crash injuries than any other city in Texas, and why we're up near the top nationally. Safety should come first, and medians make streets safer. (It is certainly fair to ask why no median is proposed south of 59, which will also be rebuilt. The answer is a few merchants who would rather have increasing numbers of serious injuries than prevent someone from turning left wherever they want to.)
Medians can also reduce congestion. Congestion is largely caused by friction, people changing lanes, turning left and so on. A median can get some of that under control. It's a good thing.
And the concept of making the median 14 feet wide at the intersections, in order to provide a little island of safety for pedestrians who can't make it across the wide street in one traffic light cycle, is headed in the right direction. But the idea of making the median that wide for its entire length (with all the damage that would cause) needs some examination, if all the extra 4 feet is for is to provide safety islands for pedestrians at intersections. Surely there's a configuration to simply put those islands where needed, rather than everywhere.
We need a time out. This project is enormously wrongheaded and demonstrates abundantly that we not only need to rethink it, but we need to bring the Design Manual into the 21st century and fast. (For more on that, see the Institute of Transportation Engineers publication
"Context Sensitive Solutions in Designing Major Urban Thoroughfares for Walkable Communities.")
. Also, the Upper Kirby District will hold a Kirby Drive Storm Sewer/ Mobility Improvements Public Meeting on Saturday, September 15, from 9-11 at 3015 Richmond Avenue in the Main Conference Room. It would good to fill the place up.
For more on this topic:
Trees for Houston
Upper Kirby District
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