Call it D.I.Y. traffic counting.
The process of pinning down exactly how many people ride bikes in Boston is a notoriously imperfect science. Ari Ofsevit, who runs the blog “Amateur Planner” — though he says he’s more “armchair” than “amateur” — was underwhelmed by the state’s data on bike use on Longfellow Bridge. The state’s most recent numbers, from 2011, suggest that a little more than 100 cyclists cross the bridge in a two-hour time frame during a peak period of the day.
Which, if you’ve ever been on the bridge during rush hour, seems like a shockingly low estimate.
So Ofsevit hatched a plan to conduct his own ridership count, Ninja-style.
“Instead of getting mad, I got even,” Ofsevit wrote. “I did my own guerrilla traffic count. On Wednesday morning, when it was about 60 degrees and sunny, I went out with a computer, six hours of battery life and an Excel spreadsheet and started entering data.”
During the two-hour period he was stationed at the bridge, he saw 463 cyclists — more than four times state estimates.
He also discovered other interesting details, too — only about 6 percent of the cyclists crossing the bridge were on Hubway bikes.
Check out the full blog post here.Martine Powers can be reached at firstname.lastname@example.org. Follow her on Twitter @martinepowers.