Thursday, September 22 marks World Car-Free Day -- an annual event that encourages drivers to ditch their vehicles for the day in favor of walking, biking, and mass transit. The grassroots network has grown to over 1,500 cities in 40 countries around the world.

Car-free commuting improves public health, eases traffic congestion, reduces pollutants that contribute to climate change, and provides significant economic savings. The American Public Transportation Association (APTA) estimates that the average American household can save $830 a month by commuting via mass transit and owning one car instead of two. At the national level, urban traffic congestion annually wastes 3.9 billion gallons of fuel and 4.8 billion hours of worker productivity, costing $81.5 billion. Congestion costs an additional $33.2 billion in fuel and productivity waste from large freight trucks.

While car travel grows more painful, commuting alternatives are innovating to become more convenient. Bus rapid transit (BRT) systems, which offer dedicated or separate lanes for buses in order to improve speed and reliability, have been deployed with great success in urban centers in the developing world. BRT systems are not as common in the United States, but a dedicated bus lane through the Lincoln Tunnel allows the quick transport of 62,000 commuters between New York City and New Jersey each workday. New high-quality bike lane networks encourage car-free commuting, especially among those not bold enough to navigate car lanes or busy sidewalks. Bike-share systems, which allow point-to-point travel between a network of docking stations, provide a convenient mode of entry for new bike commuters. Washington, DC’s popular bike-share system celebrates one year of operations on September 20, while New York City has announced plans for a similar program.

World Car-Free Day brings attention to an important issue, but it is important to remember that the climate, economic, and health benefits of car-free commuting cannot be achieved by doing so one day out of the year. Major behavior shifts are needed, as are systems and infrastructure that encourage a car-free lifestyle. A strong showing on September 22, however, can demonstrate that such changes would be welcome.