People who have biked in the city for years know to stay clear of the door zone, and think nothing of taking the middle of the road in busy traffic. This may be why a few seasoned cyclists find bike lanes to be too restrictive — a relatively confining space to one side of the road.

Greener riders know less about doors. They fear the cars blowing past their backside at 35 miles per hour. Their line of travel is more likely to be as close to the doors as possible, sometimes even swerving to avoid the rear view mirrors. A bike lane for a person in these circumstances can feel like a spacious room to spread out in, a place to exist.

Just the comfort they provide might be reason enough to support bike lanes if we’re being generous to beginning cyclists, but if we really wanted to find out the effect bike lanes have on where people ride, we’d want an average of all riders both with and without a bike lane, right?

Yea sure. That makes sense. But in the United States it didn’t begin that way. It’s kind of a long story, but an interesting one.

Europe did it right, of course. Increasing traffic congestion and decreasing cycling rates were alarming countries like the U.K., Germany, Amsterdam, and Denmark in the 1970s. But instead of letting their cities succumb completely to the car culture that was already swarming over the U.S., they began studying ways to boost cycling rates and carried them out, always gathering data and experience along the way. Today they have among the highest cycling rates in the developed world.

But in the U.S., unfortunately, the system was less predicated on careful study and results, and more on the “squeaky wheel gets the grease.” Not to mention car culture was far more ingrained to begin with.

There was certainly a bike boom going on back then. And there were a number of great bike advocates were citing public health benefits and many of the same precepts advocates voice today. But there were also more complicated characters, like John Forrester, a very squeaky wheel.

Forrester got his start defending cyclists’ right to ride in the road as opposed to being relegated to the sidewalks, but his biggest contribution to safe riding was divining the fundamentals of “vehicular cycling” that are still used as the basis for most if not all classes on how to ride safe in and among traffic today. But some would say he got a little dogmatic about his riding style. He asserted that it was the only way to ride and defended against designs that didn’t treat bikes in precisely the same way as cars or trucks. To him, that meant any and every separate bikeway, cycletrack or bike lane. His stance was easily adopted by the American Association of State Transportation and Highway Officials (AASHTO), perhaps because it recommended doing nothing to change their current practices. For decades, AASHTO recommended against bike lanes, which stymied all manner of bike projects nationwide.

John Allen, an electrical engineer in Waltham, Mass., learned Forrester’s techniques and churned out his own version of vehicular cycling in a pamphlet still useful today and found in many bike shops. He also picked up Forrester’s personal habit of railing against against bike lane projects in almost any form they took. Allen was a member of MassBike, our statewide bike advocacy group, as was Paul Schimek, Boston’s first bike czar. Schimek told journalist Jeff Mapes he believed 90 percent of what Forrester said, even though Forrester was “shrill and nasty.” Forrester was noted for making personal attacks against those who opposed his viewpoints.

Allen, Schimek and others did a good job protecting Boston from separated bikeways. Dozens if not hundreds of streets were repaved or reconstructed during the 70s, 80s and 90s, all without bike lanes. Most recently, Schimek and others managed to influence the removal of bike lanes from plans for the Rose Kennedy Greenway and a reconstruction of Huntington Avenue, which passes through several university campuses.

These days however, we have the data that should have been collected back in the beginning. It comes from Europe, from American cities that managed to go their own way, and more recently from academic researchers all over the country who have been compelled to study the issue. Even MassBike, Allen and Schimek’s alma mater, has turned the corner and now openly supports bike lanes and even experimental separate bike facilities. Below are the main arguments and scientific data that have caused this sea change.

The Door Zone
A typical argument from this anti-bike-lane crew is that bike lanes put riders closer to or inside the door zone. The city of Cambridge’s 2005 Hampshire Street Study has been called the “nail in the coffin” of that argument. Instead of moving into the door zone after a new bike lane was installed, people moved further away from it. But to really understand the significance we need to understand some basic statistics. The average distance away from the cars increased by only 2.4 inches. But the distribution of distances narrowed, so far fewer riders rode really close to the doors and about 8 percent of riders moved completely out of the door zone.

The Raw Safety Factor
Unfortunately there has been very little research on whether or not bike lanes decrease injury rates. This is at least partly due to the poor job many American cities do tracking bicycle accidents, making it more laborious for researchers to track incidents on particular streets. However, one review of the international literature, called “The impact of transportation infrastructure on bicycling injuries and crashes,” looked into what little research is available on the subject, a few dozen studies using a variety of methods. It concluded:

“The evidence to date suggests that purpose-built bicycle only facilities (e.g. bike routes, bike lanes, bike paths, cycle tracks at roundabouts) reduce the risk of crashes and injuries compared to cycling on-road with traffic or off-road with pedestrians. Street lighting, paved surfaces, and low-angled grades are additional factors that appear to improve cyclist safety. The major advantage of infrastructure modifications, compared to helmet use, is that they provide population-wide prevention of injury events without requiring action by the users or repeated reinforcement.

”Given the influence of safety on individuals’ decisions to cycle, the importance of cycling modal share to safety, and the ancillary benefits of this active and sustainable mode of transportation, infrastructure enhancements have the opportunity to promote an array of improvements to public health.”

The Safety In Numbers Effect

Bike ridership is up in New York, so the downward trend in injuries on individual streets such as Broadway and 9th Avenue, as noted above, could also be attributable to the greater number of cyclists on the road. Injuries are in fact down all over the city as the chart at right shows. In 2003 a fellow named P.L. Jacobsen documented the incidence of this effect all over the world in a study called “Safety in Numbers, More Walkers and Cyclists, Safer Walking and Cycling.” He compared towns, cities, and countries and found distinct correlations between higher cycling or walking rates and lower injury rates. The evidence he cited and that continues to pile up for ‘Safety in Numbers’ is overwhelming.

Build it, and They Will Come?
Since we know higher numbers of cyclists help make city streets safer, there is a recent upsurge in interest from American cities in building bike lanes. There is little scientific evidence that building one bike lane on its own would increase the number of cyclists on that road. But an international review of municipal bike programs and policies conducted by researcher John Pucher and others and published in Preventive Medicine in 2010 found that cities with comprehensive programs that included a connective network of bike lanes, paths and other bikeways were successful in increasing cycling rates.

So instead of “build it and they will come” perhaps the appropriate analogy is a garden. Build it, plant the seeds, water them, keep the weeds out and they will come. In any case, several cities that have built bike lane networks have seen major increases in the cycling rate. Portland, Oregon is a prime example, as the chart at right shows.

Health is Wealth
The final cap on the argument for bike lanes is the well-established fact that biking is good for health, and more biking overall has a positive effect on public health, which translates to lower health care costs, quality of life, and many other factors.

On the grand scale, the health benefits of cycling outweigh the risks of injury or death from car accidents. Perhaps the most convincing of the studies that show this is a large and long-term population study from Copenhagen. Nearly 7,000 people were asked a wide variety of questions, including whether or not they biked to work or not. The study then checked medical records on these individuals 15 years later. Even after adjusting for other risk factors, those who didn’t cycle to work experienced a 39% higher mortality rate from any cause than those who did cycle to work. Of “any cause” includes, of course, traffic accidents.

Now everyone is entitled to their own opinion, but the Boston Cyclists Union and a growing majority of bike advocacy groups around the world—including Livable Streets Alliance and MassBike here in the Commonwealth—are of the mind that bike lanes and other separate facilities for cyclists are the key to increasing cycling rates and making streets safer for all road users.