Safe and Healthy Routes for Urban Bikers
Investing in bicycle infrastructure is good for people and cities
For urban cycling advocates, investing in bicycle infrastructure can help undo the damage of decades of bad decisions, which have left too many places with a car-centric transportation system. The thinking — which was perfectly expressed by Copenhagen bicycle ambassador Mikael Colville-Anderson during his recent TED talk — is: “Bicycling is the most potent medicine we possess … for designing livable cities.”
Advocates say designing for bikes will yield broader benefits, making our cities healthier places to live. Shifting from motor vehicle based transportation to cycling produces multiple wins for cities: reduced greenhouse emissions and traffic congestion, and gains in air quality, fitness, and the economy.
Biking can also be a very efficient mode of transportation, especially in highly dense environments. The You Are Here project from the Social Computing Group at the MIT Media Lab recently released a series of interactive maps enabling users to determine the best mode of transportation from various locations in eleven cities: walking, bicycling, public transit, or driving. As an example, they looked at Manhattan and found that outside short-range distances, where walking is fastest, biking often wins out for most locations leaving from midtown.
Cycling is not without its risks. Good design can help mitigate them.
Bikers face an uneven match with cars and trucks, should an accident occur. The good news is designers and planners have found many ways to mitigate these risks through good design and increased awareness. Best practices, such as those listed in the NACTO Urban Bikeway Design Guide, have been implemented across the country with much success. A popular recent video from urban planner and designer Nick Falbo adapts a promising Dutch design solution for the continually sticky issue of intersections – still one of the more dangerous places for cyclists. And, in general, the more cyclists on the road, the safer conditions are for all cyclists. In its first year of operation, with estimated 8.75 million trips, New York City’s Citi Bike bike-share program has seen zero fatalities and just 25 visits to the emergency room. Capital BikeShare in D.C. also has yet to see any fatalities after several years in operation.
Fewer solutions have been determined for the longer-term risk of increased exposure to air pollution. While the overall health benefits still appear to outweigh the risks, urban cyclists can inhale significant amounts of pollutants from nearby motor vehicles.
Suggestions for decreasing this risk — taking quieter back-routes, biking during off times (especially in the morning since ozone peaks in the afternoon), avoiding intersections, and wearing a respiratory mask — tend to place the burden on cyclists. They are also not much use to urban commuters and portray cycling as niche and unsafe, an issue at the core of Colville-Andersen’s TED talk. The bicycle ambassador, who is opposed to wearing helmets — he claims the science is split on their effectiveness and government mandates on helmet-wearing have tended to suppress rather than increase biking — would almost certainly not approve of the suggestion that cyclists wear face masks. (His arguments on helmets and the culture of fear are interesting and worth a watch).
A new study from the Harvard School of Public Health that compared exposure to air pollution — specifically “black carbon” and nitrogen dioxide — on bike lanes adjacent to traffic versus bike paths separated from traffic may offer guidance for designers, planners, and officials. In Boston, the study found exposure was impacted less by time of day or traffic congestion levels and more by proximity of cyclists to the traffic itself and the presence of greenery. Cyclists on the green bike paths separated from vehicular traffic saw the least exposure, an effect increased both by distance from cars and by the green buffers.
The study’s most significant case study focused on the bike path along Sturrow Drive, a major parkway along the Charles River, 100-feet away from the road and separated by a row of trees. There, fewer intersections reduced exposure, and trees both pushed fumes up and away from the path and collected particulate matter on their leaves.
Green buffers can be easily integrated into the existing urban fabric. Doing so will help keep cyclists safe and healthy, but all citizens will reap the benefits.
Yoshi Silverstein is the ASLA 2014 communications intern. He is a Masters in Landscape Architecture candidate at the University of Maryland. He focuses on landscape experience and outdoor learning environments.