It turns out that protected bike lanes speed traffic up while decreasing accidents
Who'd have thunk it?Protected bike lanes are awesome, no doubt about it. We're very excited to see them become more popular all around the US, and that includes New York City. The city has added over 30 miles of protected lanes in the past 7 years, and doesn't plan to stop growing the network any time soon.
See below for our favorite graph! (keep scrolling)While nobody will argue that protected bike lanes aren't a great way to make cyclists a lot safer, many motorists argued that they would slow down traffic and make congestion worse. It turns out that this isn't the case in most places. The New York City Department of Transportation (NYC DOT) did a study on the impact of the protected bike lanes on traffic, and what they found is very encouraging.
First, not surprisingly, the rate of injuries fell significantly. But on Columbus and 8th avenues, the time required to drive a certain distance dropped significantly compared to before the lanes were there, while on 1st Avenue there was just a slight increase (could be within the margin or error -- driving around isn't an exact science).
Why did things turn out that way?
"One is that, for the most part, driving lanes weren't actually eliminated when they bike lanes were built — they were simply narrowed. Additionally, the design of the bike lanes included a dedicated left-turn lane at most intersections, allowing cars to wait to turn left without holding up traffic," writes Vox.
Here's a look at average speeds during different times of the year in the Central Business District, using taxi cabs as a proxy for general traffic:
As the graph says, during that period the number of people working there went up significantly, so the fact that average speeds remain pretty stable shows that the bike lanes don't have any negative impacts.
And since the number of cyclists went up a lot, this means that more people are using the same roads, and they're all safer doing it (the NYC DOT calculates that there's been a 75% decrease in average risk of a as of 8/14/2014*
serious injury to cyclists from 2001 to 2013).
And just because we love that graph, here's a way to visualize how much cheaper 1 mile of protected bike lane is compared to 1 mile of roadway: