Convincing people to take a streetcar or bus to work can be difficult.

But downtown transit routes on both sides of Tampa Bay have seen substantial increases in ridership after tweaking stops, hours, frequency — and making their services free.

The Downtown Looper in St. Petersburg and the TECO Line Streetcar in Tampa saw ridership jump beyond expectations after organizers eliminated the fare for each service in October. The decisions to make a downtown route free in each city happened at the same time, but were independent of each other.

The record ridership comes at the cost of lost farebox revenue. But it's a tradeoff transit officials are happy to make, saying benefits such as fewer cars on the road and the economic impact on local businesses makes the loss worth it.

Still, public transit already is heavily criticized for often not bringing in enough revenue to cover its costs, giving opponents more cause for concern.

"We do have people who don't understand why we continue to put more money toward public transportation," St. Petersburg City Council member Gina Driscoll said. "But the bottom line is we have many, many more people who complain about traffic congestion. We have to solve that problem, and transit is a way to do that."

Streetcar revenue in Tampa averaged $526,000 a year between 2015 and 2017. The Looper brought in an average of $12,300 a year from its 50-cent fare, said Eric Carlson, transportation director for St. Petersburg's Downtown Partnership.

"In the transit world, it's like, why bother if that's all you're recovering out of the farebox," Carlson said.

The sacrifice at the farebox has led to record numbers since the routes became free. Ridership on the Looper increased about 68 percent and streetcar numbers jumped 167 percent.

The two transit agencies involved were able to cover the costs through a combination of grants and private contributions from stakeholders and advertisers.

In Tampa, state officials led the charge to make the streetcar free, hoping it would attract more commuters and convince people that transit was a viable option for getting to work downtown. The Florida Department of Transportation gave Hillsborough's transit authority a three-year grant of about $2.7 million to cover fares and help boost ridership. The agency also decided to extend the hours and run the streetcar more frequently.

Five months in, ridership has about tripled. More than 356,000 people boarded the streetcar between October and February. That number is more than the entire ridership for any year since 2013, Hillsborough transit authority interim chief executive Jeff Seward said.

As a result, the agency will add another streetcar to the route on weekends starting in April.

"People are being left at stations because we're so full," Seward said. "I never thought I would stand in front of the Tampa Historic Streetcar board and say, 'You know what? We have a problem with too much ridership.'"

Seward wasn't the only one who felt that way. The trolley historically suffered from low ridership and low revenue, limiting the cars to 20 minutes between stops.

"At some point, they were talking about doing away with it completely," state Modal Development Administrator Ming Gao said. "So we were looking at ways to make it more viable for both commuters and tourists."

David Pieper, who rode the streetcar last week, said it's a problem officials should've addressed earlier. He'd like to see the service stay free and the route go deeper into downtown.

"I feel they left it as a tourist opportunity instead of making it a real option for the community," Pieper said. "They're leaving us hanging even though it's our tax dollars paying for it"

The streetcar saw its biggest numbers in December when more than 91,000 people rode the route that connects Ybor City, Channelside and part of downtown Tampa. Just under 32,000 people rode the line in December 2017 when the fare was $2.50 per trip or $5 a day.

"What it does prove to me is that $5 to ride the streetcar was just too much," Seward said. "People coming off the cruise ships and going to Gasparilla are happy to pay that, but our citizens who want to ride it to work or restaurants, they're just not going to spend $5 and wait 20 or 30 minutes to do it."

What also stands out to Seward is that 25,500 riders between October and February boarded the streetcar before 11 a.m. on a week day. Though the agency hasn't conducted a formal rider survey yet, that time of day indicates people are more likely to be using it for work as opposed to tourism or entertainment. Previously, the streetcar didn't run at all in that time frame.

Mary Hill, 38, takes the trolley from her home in Ybor to her office in the Bank of America Plaza downtown whenever she isn't able to carpool with friends. Hill and her husband decided to become a one-car household about six months ago, largely because they live so close to where they work.

Plus, dealing with parking was a pain, she said. The garage at her building was full, and Hill said other downtown options are "impossible."

Hill, who rode the streetcar before the change, said the ridership increase since the fares went away is substantial

"There was nobody on it at any point in the day," she said of her trips before. "Now, there's always somebody on board, especially during commuter hours. It's nice to always see a few people."

Christina Moulton, who lives in Ruskin and works at the Marriott in downtown Tampa, said the free streetcar saves her time and provides her a safer option when walking from her parking spot in Channelside to her job at the hotel.

The free ride isn't the only element boosting ridership, officials say. Increasing how often the routes run and how long they operate during the day also makes them a more attractive choice.

"Especially for commuters, if I can't rely on 15-minute service, I'm probably going to drive to work," said Carlson, the St. Petersburg transportation director. "If you want to attract people to use it for work, you've got to step it up. You've got to start early in the morning, run later into the night and make sure the service is frequent."

Other transit providers across the country have experimented with free service. The Kansas City Streetcar has been free since it launched three years ago. A combination of a sales tax and property assessment within a special district surrounding the streetcar help cover its costs.

"We did have naysayers in the beginning who were like, 'Wow, you had a million trips. Imagine how much money you could've collected if you charged a fare,'" communications director Donna Mandelbaum said. "But what we've seen from studies of other agencies who impose a fare, their ridership is not that high."

And because people can take the streetcar for free, Mandelbaum said that's more money in their pockets to spend in businesses and restaurants in the district.

The increase in ridership for both the streetcar and looper could make it possible for both to get additional federal funding, said Gao, the state official. It also helps support the case for extending the transit routes. Tampa officials are hoping to lengthen the streetcar, taking it deeper into downtown up toward Tampa Heights.

"I think the increase in ridership will help them make a very good case with the federal transit administration," Gao said. "That will demonstrate the people the system serves and the value it brings."

Contact Caitlin Johnston at cjohnston@tampabay.com or (727) 893-8779. Follow @cljohnst.