If you can’t count it, it doesn’t count

If a tree falls in the forest, but nobody counted it, did it even exist? We have more maps, measurements and counts than ever before, and the quantitative trumps the qualitative. Because we are flooded with information, we use numbers to filter the noise. And if something is not counted it is often ignored.

This is a big deal for cyclists and pedestrians. Car traffic is carefully measured, and using these data, roads are engineered to minimize delays and keep traffic flowing. Makes sense, right? On the other hand, modes like walking or riding bikes are often qualitatively measured. When multiple interests compete for the same resource, the engineers go for the quantified side.

I think this is happening in Chapel Hill. A college town with minimal parking and excellent bus service, walking is a huge deal in Chapel Hill, and the area near the UNC medical and public health complex has pedestrians all over the place on a weekday morning. Pedestrian-car conflicts are a big problem, and there have been two recent fatalities of pedestrians in crosswalks in this area. The crosswalk near the Health Science Library is particularly busy. But the delay for the walk signal was too long for many people, over 2 minutes. Huge groups of people would cross against the signal, and when the cross light actually changed, few if any were left to cross. I made the little video (seen above), sent it out to the UNC transportation people, and eventually Chapel Hill decreased the delay to around 70 seconds.

But this didn’t actually solve the problem. Many people still would not wait, and there were many close calls as impatient pedestrians darted across in front of the fast moving car traffic. This is clearly quite dangerous for pedestrians.

How could the town planners get it wrong a second time? Through e-mail, I asked the Chapel Hill traffic engineer to explain, but he never responded. So I went to the Chapel Hill Transportation Board last week and asked them directly. The transportation planning manager explained that the crosswalk signals were timed with the other traffic lights to keep car traffic flowing smoothly, so decreasing the delay in the crosswalk signal was not easy.

So here you have it: traffic lights are carefully timed to maximize traffic flow, but apparently pedestrian flow and safety are never fully quantified. What percentage of pedestrians safely cross Columbia Street with the crosswalk signal? We don’t really know, but we do know about stoplight timing and car traffic. So which mode of transportation wins?

This same principle applies to other bicycle and pedestrians issues: we need clear metrics. But things may be improving. In some cases, I have seen the town staff in Carrboro and Chapel Hill counting all modes of transportation. And the Carrboro Bicycle Coalition has looked into counters that could be installed on the Libba Cotton Bikeway.

It would really help if the measurements and decisions were clearly provided to the public. But citizens should insist that planners measure all types of traffic when balancing the competing interests on roadways. We have a strong local commitment to alternative transportation. If roadways are not working for pedestrians or cyclists, we need to know why not.

Posted in Blogs, Charlie's Blog
One comment on “If you can’t count it, it doesn’t count
  1. John Rees says:

    Not only that, but often it means you have cars stopping once the red is finally shown to them, and there are no walkers in the crosswalk because they have already crossed.

    I will confess when I am running on campus and I see a clear way across, I do not bother hitting the button, because I will be long gone once the light switches, and then I have needlessly delayed motorists as I was the only person there.

    It *would* make sense, to possibly increase the window between subsequent cycles: IOW, if the ped crosswalk just got the signal, to not immediately respond to the next button for a slightly longer period to offer the traffic a reasonable cycle between crosswalk stops.

    BTW, also noticed the bus cross the the zebra stripe AFTER the pedestrian light was fully lit! 🙂

Leave a Reply

Your email address will not be published. Required fields are marked *

*