The following article was originally published by Catherine Cloutier in The Boston Globe on April 17th, 2015.
Boston’s Hubway bike-sharing program began its fifth season of full operation Friday, offering residents and visitors an active alternative for public transportation.
The program never really shut down for the winter, though. It kept its 32 stations in Cambridge open, along with some in Boston, citing high demand.
Since its creation in July 2011, the bike-sharing program has grown steadily in its annual number of members, trips, and miles traveled.
Originally just in Boston, the program expanded as far as Somerville and Brookline, and more than doubled the number of its stations and bicycles. By the end of its third season, the system covered about 20 square miles, according to Hubway.
Users can sign up for a membership online or purchase a day pass at a station’s machine. From there, they can take the bike to commute or run errands, and when they are finished, return it to any station.
In 2014, the system had 12,673 members, up from 7,042 two years prior, according to Hubway.
The growth in Boston is part of a larger trend: more US cities and residents are using bike-sharing programs.
In 2010, there were five bike-sharing programs in the United States, according to data from the Pedestrian and Bicycle Information Center. By this year, 47 cities and regions had bike sharing.
Many bike-sharing operators have programs in multiple cities. Hubway’s operator Motivate, for example, also oversees bike-sharing programs in the nine other cities, including New York, Washington, and Chicago.
The type of program, which has been around in other countries since the middle of the 20th century, saw particular growth in the United States in 2012 and 2013, according to a study on bike sharing by the Mineta Transportation Institute.
In all, public bike-sharing programs exist on five continents and 712 cities.
In the United States and elsewhere, universities and colleges also operate bike-sharing programs. Three institutions in Massachusetts — Hampshire College, University of Massachusetts Lowell, and Wellesley College — have a combined 50 bicycles for student use.
The Metropolitan Area Planning Council, which coordinates the Hubway system, said a large proportion of Hubway trips are taken in conjunction with public transit.
For cities, bike-sharing programs can reduce traffic, use of fossil fuels, and pressure on the parking supply, a report by the Federal Highway Administration found. On top of that, the report found, the implementation and operational costs of these programs are fairly low.
In the United States, most of the bike-sharing programs are operated in larger cities or tourist destinations. For most of them, there are 3½ to five bike-sharing stations per square mile of the service area, according to the Federal Highway Administration report.
The number of bicycles per 100,000 residents is higher in most touristy areas, like Aspen, Colo., and Long Beach, N.Y., whereas the country’s largest cities, like New York and Chicago, offer the greatest numbers of bicycles and stations.
The cost and cost structures of these program vary, but most offer both an annual membership and a day pass.
Hubway is continuing to expand in the area. Boston and Cambridge have plans for new stations later this season, the system reported.
In a statement last week, Mayor Martin J. Walsh called the program’s growth “a testament to its importance in moving people around the area.”
“The return of the bikes has become a real sign of spring for the region,” Walsh added.