The raging debate on whether new bike lanes help or hurt business among street-level retail stores, bicycle advocates, local transportation departments, and politicians is nothing new. Seeing the same problems come up again and again, Seattle Transit Blog guest columnist, Kyle Rowe, University of Washington, set out to shed some light on the situation by "utilizing taxable retail sales data" to show what actually happened in Seattle neighborhood retail districts when bike lanes and other bicycle infrastructure were added. In his report called Bikenomics: Measuring the Economic Impact of Bicycle Facilities on Neighborhood Business Districts, Rowe argues that bike lanes have had a positive economic impact there, at least in the areas where the research was conducted.

These clashes have been popping up all over. In New York, one CitiBike rack placement was recently deemed not kosher after a Chelsea co-op filed suit against the New York City Department of Transportation (NYCDOT). According to a New York Post article, city attorney Mary O'Sullivan "compared the placement of Citi Bike racks to designating streets for alternate-side parking or making a street one-way." But faced with a severe lack of data, retail stores have a hard time proving that putting in bike lanes or other infrastructure directly loses them business, just as planners struggle to prove the opposite.

In the Seattle case study, Rowe attempted to "bridge that gap in knowledge" by using public retail sales data to show what happened to neighborhood business districts when bike lanes and other facilities are constructed.

In the first example, Greenwood Ave N, the area "performed very similarly to the neighborhood-wide control, while differing slightly from the neighborhood comparison," after the bicycle lane was put in.

For NE 65th St, the bicycle lane appears to have dramatically improved sales in the area. According to the study, two quarters after the construction of the project (and removal of parking), NE 65th St "experienced a 350 percent increase in sales index, followed by a jump to 400 percent" in the next quarter.

Though many factors could lead to the increase of sales in the second example, the study shows that in these two cases the addition of bicycle lanes had no negative effect on businesses in the districts. It makes sense, too: According to a 2012 study of 90 large American cities, if you build a bike lane, it will be used.

However, there are still other reports that dispute the positive effect of bike lanes on retail districts. In a 2011 survey of select retail stores on the Upper West Side of Manhattan, customers claimed they couldn't find parking and businesses complain about delivery issues. "Parking tickets are up," according to an article in The New York Times, "and business, apparently, is down."

To counter these claims, NYCDOT released a report in late 2012 claiming that businesses saw an improvement in retail sales of up to 49 percent if they were near protected bicycle lanes. This data, however, related to a three-block strip of 9th Ave. Otherwise, there was only a 3 percent boost Manhattan-wide.

The scales, it seems, will tip towards the side with the more solid data. A simple Google search can throw you into either side of the debate, depending on which link you click. Rowe's study is a great start. If a study like this was in every city that regularly makes updates to their bicycle infrastructure, the obstacles for bicycle advocates might not be so widespread.

This guest post is by Phil Stamper, ASLA PR and Communications Coordinator.

Image credit: Seattle Transit Blog Flickr, Mike Bjork, 2009