Want to Measure Bike Ridership? Count People, Not Miles of Bike Lanes

Bicycling on the Dearborn Street bike lane

A bicyclist braves Dearborn Street, past where the protected bike lane ends.

National Bike Month in May results in an inevitable flurry of national press articles trumpeting bike commuting. The headlines can get pretty repetitive: “Top 10 Cities for Bicycling,” “Bike To Work Rate Grows,” “City Adds 10 More Miles of Bike Lanes.”

Yet even though these articles might seem promising, there’s precious little understanding about what really makes a place “bike friendly.” Easy measures, like how many miles of bike lanes have been painted, obscure the fact that we usually have no idea how many more people are bicycling. Having miles of bike lanes matters little if those bikes lanes don’t serve anyone. After all, if a bike lane gets striped in a forest and no one is around to use it, does it make that forest bike friendly?

What matters more is how many more people are bicycling, whether on those bike lanes or otherwise. Bicyclists will vote with their feet for quality bike lanes: ones that have clear markings, connect to each other to create a network, provide legible space at conflict-prone intersections, and exist along streets that are comfortable and direct.

Chicago Tribune architecture critic Blair Kamin touched on these points in his recent critique of Chicago’s cycle facilities. In one of the Tribune’s few worthwhile recent articles about bicycling, Kamin interviewed an executive at an organization that tries to make it politically palatable to build unconventional bike lanes:

“Chicago has made incredible progress over the last few years,” said Martha Roskowski, vice president at People for Bikes, a Boulder, Colo.-based advocacy group. But, she added, “Chicago also has a ways to go.”

“A ways to go” is being charitable.

Addressing the gaps in the city’s network of protected bike routes, Roskowski said: “People evaluate a potential bike ride on the basis of the weakest link, the scariest part of the trip, which might be a really busy road you have to ride along or across. People have tolerance for a little bit of that. But if it’s sustained or if it feels dangerous, they just won’t do it.”

Those many Close Calls, bike lanes that deteriorate soon after installation or forego maintenance, cross bumpy pavement, and dodge numerous obstacles – scare many Chicagoans away from bicycling, and result in the city’s low proportion of bicycle commuters.

Since Emanuel took office in 2011, Chicago has installed 52 miles of protected bike lanes [it's installed 16 miles of protected bike lanes], which use a variety of means — plastic pylons, striped pavement markings and non-curbside parking spaces — to separate bikes from vehicles. That brings the city’s total bicycle lanes to 207 miles.

207 miles is a pretty cool number. How many miles of streets without bike lanes do we have? That’s just over 4,000 miles, minus those 207. Only one out of every 20 miles of Chicago roads has a bike lane.

Why doesn’t Mayor Rahm Emanuel talk about how many people have taken up bicycling since he took office, or how many more fun and healthful bicycle trips Chicagoans have taken in those 52 miles of new protected (or, more likely, simply buffered) bike lanes? He can’t, because nobody knows. The Chicago Department of Transportation has a bike counting program — but a study released today by Portland State University researchers highlights its unreliability. The study [PDF] incorporated the city’s own counts, conducted monthly on Milwaukee Avenue at Elston Avenue and at multiple locations along Dearborn Street’s two-way, protected bike lane. The change in ridership from before to after construction was considered, but only for four hours, one day each month. That simply isn’t large enough of a sample to truly understand the bike lanes’ impact.

The changes on these two streets were then compared to a “citywide increase,” based on the Census Department’s American Community Survey. The Census covers a different period of time, counts only a small sample of those who commute to jobs, and only counts those who bike for most of their trip. Under this flawed method, it looks like a major bike lane redesign on Milwaukee increased peak-hour bike trips by only 4 percent from 2012-2013. Compared to a citywide increase of 21 percent from 2010 to 2012, it might appear that the bike lane had no effect on increasing ridership there. Better numbers, for example of non-commute trips, would probably show a different pattern.

The researchers’ video counts might cover more time, but show similar flaws. Their counts along Dearborn showed a 538 percent increase in bicycling, but does not account for how the Dearborn lane represented a huge change in the Loop’s street network. Of course many more bicyclists rode southbound on Dearborn, for instance, since doing so was illegal before. Many cyclists also probably switched to Dearborn from other, parallel streets once the bike lane opened.

On the other hand, we can track Divvy bike-share use down to the minute. Divvy’s operator announced that Saturday, May 24, was Divvy’s highest ridership day ever. This was then eclipsed by nearly 4,000 more trips the very next day, probably helped in no small part by the Bike The Drive event. The amazing level of detail that bike share data make available gives us a strong basis to make informed decisions about bicycling routes – but only for Divvy users, who are only a fraction of bicyclists citywide.

Without good information on how many people are riding bikes, and who they are, there’s no way for the city to measure its progress against its own Bike 2015 Plan, which set out as its goal that “five percent of all trips less than five miles are by bicycle.” (This measure was a big change from prior plans, which never included similar performance measures.) And without a way to measure progress, it’s impossible to hold the city accountable for the steps that it takes along the way.