Nancy Folbre is an economics professor at the University of Massachusetts Amherst.

More Americans are biking or walking to work these days, in part because public-sector investment is improving the infrastructure they need to get there safely. Further public investments in bike paths and bike lanes are likely to offer a big social payoff.

Federal spending on bicycle and pedestrian infrastructure has more than doubled since 2006 but amounted to less than $4 a person in 2010.

This chart, a snippet of a larger infographic by Kory Northrop, a graduate student at the University of Oregon, that illustrates differences across states and highlights the top 10 major American cities for bike commuting, draws on data from the American Community Survey for 2009.

Kory Northrop; data from the Federal Highway Administration.

Portland, Ore., tops the list, with 5.8 percent of workers riding to their jobs on a regular basis. Snowy Minneapolis comes in second, at 3.9 percent, and Seattle third, at 3 percent. San Francisco, despite its hills, is nearly tied with Seattle. Smaller cities are not included in this ranking, but some, like Boulder, Colo., and Eugene, Ore., have higher bike-commuting rates than Portland.

At last count, New York City was still below 1 percent, but that may be changing, with the recent large expansion of bike paths there.



According to Bicycling magazine, all the above-mentioned cities rank among the top 10 in terms of bike infrastructure.

Some people regard bike paths as invasions of sacred car space. In March, John Cassidy of The New Yorker ranted online against their expansion in Manhattan. He was immediately reproved by scores of his readers, as well as by a commentary in The Economist, “The World Is His Parking Spot,” that applied basic social cost-benefit analysis.

Here is the economic logic behind increased efforts to promote bicycle use:

Cars enjoy huge direct subsidies in the form of road construction and public parking spaces, as well as indirect subsidies to the oil industry that provides their fuel. These subsidies far exceed the tax revenue generated by car use (as this excellent discussion of the technical issues at stake in these calculations makes clear.)

Yet cars impose major social costs: their use contributes to global warming, traffic congestion, accident fatalities and sedentary lifestyles.

Bicycle use is good for both people and the planet. In a country afflicted by obesity and inactivity, people who get moving become healthier. Riding a bike to work or to do errands is far cheaper than joining a gym. Cutting back on gas consumption improves air quality, reduces dependence on imported oil and saves money.

Increased bicycle use is practical and feasible, especially if it can be combined with effective public transportation for long-distance needs. As John Pucher of Rutgers University (dubbed Professor Bicycle by some of his fans) explains, about 40 percent of all automobile trips in metropolitan areas are less than two miles – a distance easily biked.

International comparisons in use rates, as well as differences among cities in the United States, demonstrate the impact of public policy. Professor Pucher points out that the bike share of local trips ranges from 1 percent in the United States to 18 percent in Denmark to 27 percent in the Netherlands.

As a recent New York Times article explains, many European cities explicitly aim to discourage automobile use. Good public transportation systems help people get into downtown areas that would be less congested and thus more inviting. Bike-sharing programs are expanding in cities all over the world, including Latin America.

For bicyclists, increased numbers often lead to increased safety. As bike paths on roads attract larger numbers of cyclists, the chance of car-related accidents declines, promoting further use. Safety appears to be a major factor for women in particular.

As more people ride to work, cultural norms shift — bike commuting begins to seem less quirky. Businesses begin to recognize the benefits of providing facilities for showering and changing clothes (cheaper per person than car-parking spots).

These changes, in turn, can promote more biking. Build it and they will come: increased supply can increase demand.

Major improvements in bike infrastructure wouldn’t just make it easier to get to work. They would also create work, a high priority in our high-unemployment economy.

Construction of bike paths offers more job creation per infrastructure dollar than investment in roads. (For more details, see this recent study by my University of Massachusetts colleague Heidi Garrett-Peltier, who analyzed 58 projects in 11 cities, using an input-output model to measure employment impact).

Hats (and helmets) off to the bicycle activists and policy makers who work to promote bicycle paths and lanes. They are spinning us all in a good direction.