Archive for November 17th, 2008

From Jan Gehl’s new report on New York City (via Streetsblog), this graph nicely depicts the typical (mis)allocation of New York City’s public space. We need hardly point out the glaring gap in negative externalities as well.

I just came across an article in the ITE Journal that speaks to some of the difficulties transportation engineers face in trying to manage and provide for varying modes of travel, particularly in environments where one mode dominates.

The article, “Trial Implementation of a Leading Pedestrian Interval: Lessons Learned,” by Sarah M.L. Hubbard, Darcy M. Bullock, and John H. Thai, describes the installation of an LPI (that’s where pedestrians get the “Walk Man” a bit before drivers get the green, so that “peds” can establish their presence in the crosswalk, and also be more visible) in Anaheim, California, near Disneyland.

While LPIs, at least in urban environments, have been found to be beneficial to pedestrians, at this location, the authors found, “the incidence of pedestrian compromise on the curb was found to be higher with the LPI signal timing than with concurrent signal timing for both low right-turn demand and high right-turn demand conditions.” In other words, things got worse for pedestrians with the LPI.

The culprit, they found, seemed to be the ability for drivers to make a right turn on red (yes, the only cultural advantage of California). “Drivers waiting to turn right at the red light are often watching for a gap in the oncoming traffic and may be unaware that the adjacent pedestrians have a WALK indication.” (One could get rid of the ROTR, of course, but that would, as the authors note, may cut right-turn capacity and could “actually reduce the service for pedestrians if drivers tend to accept smaller gaps between pedestrians and drive more aggressively as the v/c ratio for the right-turn movement increases” — in other words, the idiot factor may go up).

What goes unsaid here, but what I think is a more general underlying factor, is the sort of larger modal blindness that seems to occur in more suburbanized areas, like the one in which the trial was conducted. Judging by the photos in the article, the major flow street has at least four lanes in each direction, and presumably some rather high speeds. The overwhelming feel of such environments is that they are made for cars; and indeed are filled with cars, to the extent that drivers become rather programmed to looking out for the things that are important to them as drivers — lights, stripes, other cars. Pedestrians waiting to cross at a major intersections may be the victims of a kind of blindness by the drivers — either an actual kind of “attentional blindness” (they’re not looking for pedestrians so they don’t see pedestrians), or a kind of cultural blindness by which pedestrians are marginalized, and lose the rights that have been extended to them (though the number of “crosswalk” stings going across in urban areas across the U.S. should reveal this is by no means a suburban problem). I’ve noticed in Manhattan that some of the worst places to navigate on foot are near any of the bridge or tunnel entrances — either vehicles are still used to being in less pedestrian heavy environments, or their proximity to “escaping from New York” leads to a kind of animalistic imperative in which the only consideration becomes getting that many inches closer to the tunnel — woe to the person who has to cross on foot in one of these situations.

The Boston Globe reports that post-Big Dig, bottlenecks in the Boston region, while lessened downtown, have been shifted outward — perhaps a result of more people now choosing to drive through the center of town.

It also notes:

“The cause of the delays on highways that lead into the Big Dig is, perhaps not surprising: more cars and trucks. On I-93 north of the city, for example, 202,000 motor vehicles drive past Roosevelt Circle in Medford, 38,000 more than in 1987, a 23 percent increase, according to state data.”