A Response to Hainline, Steisel, and Weinshall

I am glad that my posting on the Prospect Park West bike lanes occasioned a serious and thoughtful response (see the comments).

I wanted to reply to a few points.

They write:

(1) PPW is not simply an arterial roadway between intersecting streets (as is the adjacent roadway inside Prospect Park, which, we have argued, would be a more appropriate location for a two-way bike lane). Rather, PPW borders high-density residential blocks—with a school and elder-care facility (on one side of the street) and entrances to Prospect Park (on the other). This means that on a less-than-one-mile stretch of roadway, thousands of residents and park-goers are continuously entering or exiting school buses, wheel-chair vans, taxis, or driveways, while dozens of Fresh Direct, UPS, Fedex, USPS trucks, moving vans, and other delivery vehicles are also blocking one of the two remaining traffic lanes. This requires that drivers in the blocked lane continuously shift into a single more-heavily-used traffic lane to avoid the blockage. And since this single lane is now narrower on a significant stretch of PPW, if not the entire street (as our measurements, pace Vanderbilt’s assertion to the contrary, clearly show), there is less margin to avoid car doors opening, drivers or passengers squeezing into their vehicles, parents lifting babies from their car-seats, cars edging into or out of parking spots, or side view mirrors extending from vehicles. These circumstances, rather than producing a “calming feeling,” are more likely to produce irritated impatience, at best.

I admit that the studies I referred to are for road types different from PPW; in part this is a necessity because of the rather unique nature of PPW itself. But I am interested here in their description of all the exiting school buses, UPS trucks, parents getting babies out of cars, Fresh Direct vans, etc. Given this huge amount of stopped traffic, and pedestrian activity, to my mind the most important safety benefit we could bring to those users is a reduction of the speeds on that street — which were typically well above the speed limit prior to the installation of the bike lane. Speed, and the violating of right of way — not lane changing and merging — is the root cause of the vast majority of serious traffic injury in New York City. As I’ve said repeatedly, drivers, in their ‘irritated impatience,’ have tended to use PPW as a high speed arterial to neighborhoods beyond Park Slope rather than the neighborhood street it should be. I will take an infinite number of bent mirrors over the lives or health of any one person.

In their second point, they note:

“In addition to the option of moving the lane onto the adjacent roadway inside the park, making the PPW bike-lane one-way is the other proposal we have made as members of “Neighbors for Better Bike Lanes.”

I would take a one-way bike lane over no bike lane; but as a condition of that one-way status, I would call for a protected one-way bike lane, in the other direction, on Eighth Avenue, which suffers from some of the same speed problems as PPW.

They then note:

(1) Vanderbilt’s basic argument relies on the perception of increased safety that roadway users (drivers, bikers, and pedestrians) may have when more drivers and riders are using fewer and narrower lanes, because their awareness of other roadway users is heightened. But this perception of increased safety is not what users of PPW have experienced. In a self-selected survey of over 3,000 Brooklynites conducted by Councilmembers Lander and Levin, most people—bikers were the only exception—reported feeling less safe after the bike lane was installed (Ref. 2).

This misrepresents what I have said, and indeed highlights a problem: Perception of safety and actual safety in traffic are not always the same. When subjects have been asked to identify what they think are crash hot spots in certain locations, for example, they often choose places with low numbers of crashes, not the actual hot spots. When roundabouts are installed, it’s quite common for the local populace to protest that their safety has been compromised — when in fact, roundabouts, as have been documented in any number of studies, tend to make things safer for all road users. ‘Shared space’ experiments in Europe and the U.K. have shown a similar disconnect between perceived and actual safety.

But let’s stick to what we know: The actual numbers from PPW, which are now available, via the Brooklyn Paper:

“Crashes are down from an average of 30 in six months to 25, or 16 percent.

• Crashes that cause injuries are down from 5.3 in six months to two, a whopping 63-percent drop.

• Before the project, a crash was twice as likely to include an injury.

• Injuries to all street users dropped 21 percent.

The data also found that since the lane was installed last June, there have been no reported pedestrian injuries and no pedestrian or cyclist injuries from pedestrian-bike crashes.”

Granted, crashes involving pedestrians and bicycles tend to be underreported, but vehicle crashes, particularly involving injury, are not — and by this measure, the addition of the lanes has actually made for a safer environment for all road users. An increase in active transportation; a decrease in injury — I fail to see this as a problem.

This entry was posted on Thursday, January 20th, 2011 at 10:33 am and is filed under Bicycles, Traffic Culture, Traffic Engineering, Traffic safety, Uncategorized. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

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