Now, two big garage projects, each subsidized by a government agency, are being teed up to help ease the crunch.

But the glass boxes that have sprung up in the past decade inexorably changed the parking calculus on the South Boston Waterfront, to the point where the area is at risk of having too few spaces.

Not long ago, the Seaport District was mostly parking lots catering to suburban commuters who didn’t want to pay downtown Boston prices or use public transit.

The first is a 1,550-space “transportation center” the Massachusetts Port Authority is building on D Street near the convention center. Massport recently started construction on the $85 million project, with a goal of completing it by year’s end.


Meanwhile, the Boston Planning & Development Agency is looking for an engineering firm to design a nearly 550-space expansion to an existing garage a few blocks away, in the Raymond L. Flynn Marine Park. The city’s project, along Drydock Avenue, would cost as much as $22 million.

The $6-a-day option is long gone from the Seaport. However, many of the surface spaces that were lost have been replaced by more expensive spots in the new buildings.

But that doesn’t mean the need has gone away.

“The spaces that are going underground are now being used by the occupants of the buildings,” said Don Wiest, a land-use attorney at the Boston law firm Dain Torpy. “It looks like there’s a need for more parking spaces. The reduction in those open lots is so dramatic.”

Massport’s chief executive, Thomas Glynn, said the number of surface spaces in the area will have dropped to about 700 in three years, from about 7,000 six years ago. The garage, he said, “is replacement parking for the parking that’s being lost.”

Another reason for moving ahead with the long-planned project: a pending deal for a convention center hotel at D and Summer streets, to be developed by a team that includes Texas-based Omni Hotels & Resorts. Massport is in the final stages of negotiations with that team and wants the garage to be done before the hotel. Integrating the garage with the hotel project remains a major discussion point.


Although the garage would have about 1,550 spaces, Glynn said, roughly half are already set aside for nearby properties. Those include the Waterside Place apartment complex, where a second tower is being built, and the corporate headquarters for John Hancock Financial.

Massport officials have taken to calling the project a “transportation center” because it would include a shuttle bus stop, possibly a taxi or Uber stand, and a Hubway bike-rental station. The project would include a covered walkway along the World Trade Center Avenue viaduct to connect Summer Street, the garage, and the World Trade Center station on the MBTA’s Silver Line.

City Hall officials are also watching a steady stream of employers move into the district and recognize more parking is needed. Their focus is on the Flynn Marine Park, an industrial district, where they are planning a 550-space expansion of the city’s nearly 1,770-space garage.

Ed O’Donnell, director of real estate for the BPDA, expects construction to begin by the end of this year and be completed in one year.

O’Donnell said an influx of tenants in the nearby Innovation and Design Building could lead to a parking shortage; Reebok, for example, is moving into a new headquarters there this year, with as many as 700 employees. The garage also serves the Black Falcon Cruise Terminal, which is expecting a surge in the number of ships visiting Boston this year.


“Sometimes, on Fridays, it’s a mob scene,” O’Donnell said. “There’s a near-term, almost immediate need for more parking.”

Tom Pincince, CEO of the high-tech lighting firm Digital Lumens, remembers when he could see across parking lots to the water from his sixth-floor office on Congress Street. Monthly passes for nearby garages now cost about $450 a month, he said, similar to what downtown garages charge.

“In the [past] five years, I’ve seen a doubling of my monthly parking [cost],” Pincince said. “It was clearly timed: Every time a new building got built and took out a parking lot, miraculously my monthly rate went up.”

Jon Chesto can be reached at jon.chesto@globe.com. Follow him on Twitter @jonchesto.