They stood in a line, their wheels locked in place. Icicles hung down from their fenders, offering evidence that these vehicles weren't going anywhere until the city thawed out.

I'm not describing cars stranded on I-285 in Atlanta. I'm talking about the CAT Bikes parked at Chatham Area Transit's bike sharing station in Ellis Square last Wednesday.

If they had been given the opportunity, Jessie Fernandez-Gatti and her colleagues at CAT would have surely requested better weather to accompany the launch and first week of service for Georgia's first public bike sharing program. Nonetheless she said she was pleased with Savannah's bike sharing debut.

"We were very satisfied with the launch event and our first week operating. Despite the cold weather, there has been a good amount of activity," Fernandez-Gatti said.

"Tuesday through Thursday the stations did remain open, but unsurprisingly people were not very eager to take the bikes out in freezing weather."

Not everyone was dissuaded by the low temperatures, however.

"CAT Bike's first customers were a couple from Regina, Saskatchewan. They are avid cyclists and came to the launch because they enjoy supporting community biking initiatives," Fernandez-Gatti said. "They said the cold weather did not bother them because they were coming from -40° C temperatures in Canada!"

While bike sharing programs are becoming popular in cities across the United States, not everyone is familiar with the concept. That can create misconceptions about how bike sharing operates. Customers can purchase a 24-hour, 7-day or annual membership at a sharing station or online. Touching the membership card against a sensor releases the bike from the dock, and off you go. When you are done with your trip, return the bike to the dock. The "How it Works" page on the CAT Bike website (catbike.bcycle.com/how-it-works/) describes this sequence of events as sign-in, select, ride and return.

CAT Bike uses bicycles and docks manufactured by B-cycle, which is headquartered in Madison Wis., and operates bike sharing systems in Denver, Austin, Charlotte, Nashville and other cities.

Fernandez-Gatti said she has received questions about the fee structure, which includes a 50 percent discount on annual membership for students.

"The membership fee purchases access to the bikes and 1 hour (or 2 hours for annual members) to ride them. The usage fee kicks in after that hour as a charge to continue to use the bike. The fee structure is similar to renting a movie. The idea is to encourage people to return the bikes so other people can use them. This way, the bikes are available as a mobility option for getting around Savannah," she said. 

CAT Bike's usefulness as a mobility option will increase as new stations are added. Fernandez-Gatti said additional locations are being discussed to grow the service beyond the Ellis Square and Joe Murray Rivers Jr. Intermodal Transit Center stations.

"Factors that will be important to determine future locations of stations include amenities and attractions in the surrounding area, walkability and bikeability of the area, and proximity to other stations," she said. "For the moment, the focus is on expanding CAT Bike in the downtown and midtown areas so there is an extensive network that can support the mobility needs of residents and visitors. We have had a few initial inquiries about sponsoring stations and we expect CAT Bike to expand rapidly."

Until then, the good news is CAT Bikes are equipped with integrated cable locks so they can be temporarily secured at locations away from the two stations. Once the end of the cable is inserted into the locking mechanism, the key is released.

Elise Colcord, community manager at ThincSavannah coworking space, was a little confused about how to use the lock on her first CAT Bike trip, but she said she'd be ready for the next ride.

"I will absolutely use it again. I think it's a great way to get around town, especially a town like Savannah," Colcord said. "Since I work downtown, I imagine I will use it for every work errand. Outside of work, I think it will be nice to use for any type of local event."

She described using bicycles for short trips around the Historic District as "practical" and "better for site seeing, health, and removing the stress of parking and the occasional ticket that may accompany it."

As of Jan. 31, 25 CAT Bike memberships — including three annual memberships — had been purchased, according to Fernandez-Gatti. Not bad considering Savannah was under a very rare winter storm warning for part of the week, leaving downtown largely deserted.