Lewis Center Researchers Speak Out About Recent Article On Bike Lanes’ Effects On Traffic Congestion

Herbie Huff, a Research Associate at the Lewis Center, and Madeline Brozen, Program Manager of the Lewis Center’s Complete Streets Initiative, recently co-authored a letter disagreeing with the measure of congestion used in a recent story about bike lanes and traffic on the popular blog site, FiveThirtyEight. In the original article, the FiveThirtyEight authors measure congestion by calculating the V/C ratio, the flow of cars over a period of time divided by the road capacity. Using this measure, they then analyze data from Minneapolis streets and a New York City street containing newly implemented bike lanes. This led the FiveThirtyEight authors to conclude that bike lanes did not greatly increase congestion on these streets. In their letter, Huff and Brozen point out that V/C ratio doesn’t measure congestion, so an analysis based on this ratio can’t draw conclusions about the effects of bike lanes on congestion. They note that traffic congestion could be measured with traffic speed, traffic density, or travel time. Moreover, they call for a more complete picture about other related effects of the newly-placed bike lanes. Huff and Brozen close their letter by calling for greater consideration of how transportation affects people and their behaviors. For the original article and Huff and Brozen’s rebuttal, click here and here. Streetsblog USA also posted on the rebuttal piece here.