More Bikes Lanes On Less Congested Roads

Comparison of before and after counts of vehicular volume-to-capacity ratio shows replacing car lanes with bike lanes may not adversely impact vehicle traffic when bike lanes are constructed on less congested streets.

1 minute read

April 15, 2014, 7:00 AM PDT

By Helen Brown


Gretchen Johnson and Aaron Johnson seek to answer how new bike lanes impact drivers, especially when they take the place of an existing vehicle lane: “It seems that unless a ton of people start commuting by bicycle, giving away a lane would cause increased car traffic. But is this really the case?”

By comparing vehicular volume-to-capacity (V/C) ratio before and after bike lanes have been added, Johnson and Johnson reveal that: “Taking away a lane does significantly increase the estimated V/C ratio during rush hour...But it’s not at a high enough V/C ratio where traffic will get really congested and start slowing down.”

Their recommendations regarding where to place new bike lanes: “Bike lanes don’t cause a lot more congestion if you put them on the right streets…if you start with roads that are well under capacity, you’ll only increase the congestion a little bit. And it may not even be noticeable.” 

Friday, April 11, 2014 in Five Thirty Eight - Life

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