The great freeway battles of the Sixties and Seventies are over. It's safe to say few new freeways will be punched through existing neighborhoods.
But transportation engineers are still busily at work updating and improving existing roads, generally by widening them, adding lanes, smoothing curves, improving visibility, and letting traffic flow freely and more quickly. The results, ideally, include fewer backups, less sudden stopping, and a reduction in accidents.
That's great, if you're behind the wheel. But it turns out that improvements that make it easier for drivers not only make neighborhoods less pleasant, they actually make them more dangerous for people who, ummm, actually live there.
Manhattan traffic, by Flickr ruser JamesH2008Enlarge Photo
At least, that's the conclusion of a nifty little essay called "Confessions of a recovering engineer," in which Minnesota traffic engineer Charles Marohn essentially issues a mea culpa for the sins his profession has inflicted on the people who happen to live in any of the areas subjected to traffic "improvements."
He points out that improving visibility for drivers often means removing trees in a wide swath on each side of the road, including those that shade residents' houses. And that widening roads to provide left-turn lanes, shoulders for breakdowns, etc., often means taking large chunks of what had formerly been homeowners' front yards.
The crux of the issue, he points out, is that traffic engineers prioritize as follows: First comes traffic speed (which rises), then comes traffic volume (which also rises), followed by cost (fewer tax dollars spent is better), and finally safety (often measured only in terms of cars, e.g. fewer vehiclular accidents).
Property owners and residents, he notes, would likely put safety first, then cost. Higher traffic volume and speed may not be particularly important to them, and may in fact be hazardous to local pedestrians who now find themselves living next to a greater number of cars whizzing through at higher speeds.
It's the old people-vs-traffic argument. It's not a new one, but the essay ends with a kicker: According to a 2005 article in the American Planning Association Journal, it turns out that "narrower, slower streets dramatically reduce accidents, especially fatalities."
The best way to avoid accidents , in other words, is to slow down traffic (not including limited-access roadways designed to highly specialized Interstate-grade standards).
The "livable streets" movement has been gathering steam for three decades now, since the influential 1981 book of the same title by Donald Appleyard et al (only available used, but scheduled for republication next summer). Along with other evolving transportation practices, it's chronicled daily on the Streetsblog network of sites, Infrastructurist, and others.
Since High Gear Media has numerous engineers on our staff, we just wonder: Couldn't he have titled it "Confessions of a recovering traffic engineer?"
Still, well worth reading.