Last night the DOT presented the results of its Prospect Park West bike lane study to the local community. As we noted yesterday, the report asserts that the bike lane has made PPW dramatically safer and greatly reduced speeding, while also encouraging cycling (and complaining). But critics of the bike lane, including the group Neighbors for Better Bike Lanes—which is led by former sanitation commissioner and deputy mayor Norman Steisel, as well as former NYC DOT Commissioner Iris Weinshall—say the DOT's glowing report is fishy.

In a well-timed article in the NY Post, Steisel's quoted saying, "The community asked for all the underlying data, in its raw form, and instead DOT intends to present a rosy summary. We are getting only what DOT wants us to see. We have a right to more." His group did their own study, recording video of bike usage for a two-week period, 12 hours each day, at the northern end of the bike lane at Carroll Street. Steisel tells the Post they "discovered bike usage was one-third to one-half of the volume the agency reported counting." Critics also said that one of the DOT’s “before” count of weekday cyclist volume on PPW was conducted on a rainy day, thus distorting the then/now comparison.

There were heavy thunderstorms in the area before dawn that day, but the rest of June 9th saw only some scattered showers. The private consultants who do the counting for the DOT are instructed to stop if it's raining, but they apparently decided it was clear enough to proceed on that day. As for Steisel's group's low cyclist counts, DOT spokesman Seth Solomonow tells us:

As we noted last night, the counts referred to in the Post story were taken from one extreme end of the bike path. As you may understand, you can’t measure the number of riders on a subway line by how many are still on the train at the last stop, and the same rule applies here. Our counts were taken at more central locations along the lane and we also counted hundreds of cyclists on side streets—many of whom had left PPW before reaching the north end of the street.

The safety results are enough to declare this project a success. Crashes involving injuries are down 63%, and speeding on the corridor is down from 75% of cars to just 20%. There has been no change in traffic volumes or corridor travel times.

Neighbors for Better Bike Lanes submitted a FOIL request two months ago requesting the raw data used in the report. Streetsblog reports that last night Russo explained the end of the study period was December 31st, so the DOT had not even finished collecting its data until 20 days ago. And Solomonow tells us, "As we said last night, we plan to provide the data backup to the board. And regarding the document request, we informed the requestor in writing that this would be complete approximately 30 working days from the letter (i.e., Jan. 28), and we intend to comply with that."

But even some bike lane supporters are troubled that the DOT has not yet released the raw data. Matthew Noah Smith, who used to volunteer with Transportation Alternatives but doesn't represent the group, was at the meeting last night, and tells us:

Folks seemed only marginally more cranky than your average collection of Park Slopers would be... The report though, is just a summary of data collected over the past six months as compared to data collected over six month periods across the past 4 years. A summary is to be expected since looking at raw data does not make a good powerpoint presentation.

Several people there, though, wanted to drill down a bit into the data since to some of us it seemed, at least at first blush, to be a bit fishy. So, people asked for the raw data. We were denied. The DOT reps there made noises about handing some of it over to CB 6 and so on. But, when people really started pushing, they just changed the subject. So, the question is: will the DOT provide us with the raw data? Here are two other things to consider: 1. The raw data is collected by a contractor, not by the city. 2. The raw accident data consists of police reports and therefore has private info on it.

I also think that the legitimacy of attempts at public justifications like this one depends a great deal upon the transparency of crucial steps in the process. Most importantly, citizens should be allowed to inspect the raw data that supposedly supports statements like, "We have quantitative evidence that the PPW bike lane has made everyone a lot safer."