Counting Traffic pt 2

So here's my overdue post from my Harvard Bridge count. Tuesday afternoon, the same day as my Museum of Science Bridge Traffic count, I sat for another two hours, on another bridge, and counted traffic

My view to the right

My view to the left. What a beautiful day to waste!

I sat on the inbound side of the Harvard bridge, close to the Cambridge river bank, at approximately 360 smoots. Surprisingly, traffic was not at all bad (in both directions). Thus, Not only was I able to divide my counts into fairly precise bins of 7.5min, I also managed to record each wave of cars separately and differentiate between cars coming from Mass. Ave. and Memorial Dr.

My Tally Sheet

I'm dead tired so I don't think I'll be saying much. But briefly...

Open Office's Rendition of my Pie Chart

So it's interesting thing how the ratio for different modes of transportation changed. There were a lot more cyclists crossing the Harvard Bridge, and slightly fewer pedestrians. Harvard Bridge is a much longer bridge and it seemed unlikely that many of these people were commuting to and from work. Also, I should note that I was recording the inbound side of the bridge during the evening commute. If it included any commuters, they would be reverse commuters. Also, the plot isn't up yet, but vehicular traffic doesn't actually increase that much (maybe ~20%). Just from my observation, the outbound side of the bridge also didn't seem to increase much in volume.

Anyway, a lengthier review of the data should be coming soon, but not before Parking Day! We've moved location to Inman square now and the weather looks like it will be great! I'm quite excited! Please look forward to the next entry!

Counting Traffic

So today I volunteered to count the number of bicycles, pedestrians, and cars crossing various bridges into and out of Boston during rush hour. I got assigned to the bridge near the Museum of Science inbound for the morning, and the Harvard Bridge inbound for the afternoon. I recorded in intervals of 7-8min (officially, 15 min increments)

I woke up at 6am, this is East Cambridge at 6:45a

I got to the bridge at around 6:50a and I set up shop. I brought a drum throne for me to sit on which is actually a lot more portable than I realized. I had the cushion itself inside my Chrome Citizen messenger bag and I ran the two plastic buckles through the stand, effectively strapping it in place. Outfitted with my mp3 player, pen, tally sheet, and drawing pad for support, I was ready to start counting!

My counting station

I hadn't yet decided on a method for counting, especially since the early morning traffic on the way there wasn't that heavy yet. But soon I had my strategy: keep a running count of the cars in my head while writing a tally mark for each pedestrian and cyclist that passed by. This worked pretty well most of the time, but I had a few instances where the light further down would change while a large group of pedestrians (~15) came my way. I also found out that the count sheet was totally inadequate for tallying as there simply wasn't enough room. (I had stretched it out to landscape mode already) Luckily for me, I had printed the grid out on both sides of the paper and I was able to flip the sheet every 7-8 min.

Soon I realized that counting three different things concurrently was quite the difficult task! In fact, when I looked my watch to check if I needed to start counting for the next time period, I would need to glance at it multiple times before it would register in my mind. I even needed put a lot of effort into smiling at the passersbys! And then, the unthinkable happened ...my mp3 player decided to rickroll me! (now why would you ever click that link? Just to see if I reverse-rickrolled somehow?) Being so occupied with the task at hand, I was sadly forced to listen the whole song.

Before

After

Soon the whole ordeal was over and all I had to show for it was a single sheet of paper, full of scribbles.

So I think traffic counts on bridges are unfair to pedestrians. Walking to work is only feasible for people who live nearby their workplace. I would assume that a large portion of walkers live within the same city that the work in. In the case expansive span of the Harvard Bridge, I bet the majority of those people are walking recreationally. I think this also affects people who cycle to work, but much less so. (I in fact cross over the Longfellow bridge on my way to work). My completely ungrounded guess is that the percentage of cyclist right now would be closer to 6% whereas pedestrians are much closer to 30%.

On a side note, I'd say ~20% of the people I saw were joggers, and thus unlikely to be commuting to work. Also, the green line crosses the river parallel to this bridge.

Here we actually have the breakdown of commuters in 15min increments. There's not much that I want to point out here except that it looked like the largest volume was around the 7:45-8:00 bin. Car traffic gradually increased while bike traffic peaked pretty sharply. I think this is because car commuters travel longer distances and have to plan for traffic so they need to leave a much larger window to get to work on time. In contrast, there is quite a bit more leeway on a bicycle as traffic is not usually a problem and your commute times are fairly standard from day to day. I'm curious to see how my afternoon count goes. For now, the numbers look promising!