With Port Tampa Bay's unveiling of a $1.7 billion redevelopment vision for its 45 acres of waterfront property near the Channel District, a cornerstone piece of greater downtown Tampa's potential renaissance has arrived.

The bold port plan, highlighted by the purposely sky-high 75-story twin towers, seeks to resurrect a stretch of waterfront still pockmarked with vast parking lots and aging industrial storage structures. That's commendable by itself.

"Is there a single waterfront project like this? I can't think of one like this in the country," Luis Ajamil, a Miami designer of many urban waterfronts in the United States and abroad and a project partner with Port Tampa Bay, told me this past week.

But the port project is so much more.

It joins an increasingly bold series of downtown Tampa initiatives that include Jeff Vinik's $1 billion plan to create a "live, work and play" project on his 40 acres near Amalie Arena. Backed by billionaire Bill Gates' money, Vinik's coming complex of residential, office and entertainment buildings and park space will include the new home for USF's medical school, possibly a relocated museum, a new hotel, more convention space and, Vinik hopes, a substantial corporate headquarters recruited most likely from the nation's crowded and increasingly expensive Northeast.

On top of that, Tampa's aspirational mayor, Bob Buckhorn, already is talking about developing the west side of the Hillsborough River that cuts through downtown's western edge. Just up that same river, near the riverfront Ulele restaurant, lies Tampa Heights, where another substantial development project by SoHo Capital is starting to gel.

On the northeast edge of downtown, the 40-acre Encore mixed-use development now has several residential buildings up and occupied with more to come. And downtown on the eastern edge of the river, Feldman Equities recently said it will build a 52-story mixed-use tower where the once-proposed Trump Tower Tampa was slated to rise.

If these deals come to be, they all amount to billions in fresh investments — just as Money magazine named Tampa the "best city" in the Southeastern United States.

But will they materialize as proposed? Will massive simultaneous expansion overwhelm the local market? Let's just say the bulk of these proposed developments are in the early stages and the temperamental U.S. economy can always intervene. The bigger, bolder projects could take a decade or longer to happen.

But there are a lot of deep-pocketed players behind some of these proposed projects, including Port Tampa Bay. Officials there delight in saying the port is west-central Florida's top economic engine, generating $15 billion in annual economic impact and helping employ 80,000 people. Officials want those numbers to grow.

If the port's plan feels like a project that just wants to jump on the Tampa downtown revival train, you would be wrong.

This past week, four top port executives — Ed Miyagishima, adviser to port CEO Paul Anderson; chief legal officer Charles Klug; real estate vice president Lane Ramsfield; and planning and development VP Ram Kancharla — sat down with me to offer more in-depth insights into the port's plan. The project involves 45 waterfront acres running along Channelside Drive from Florida Aquarium north, nearly to the Selmon Expressway. Luis Ajamil, CEO of Bermello, Ajamil & Partners in Miami, joined us by video conferencing.

I asked the officials if their plan — including two 75-story towers that would soar far above any other building in the city — would have ever materialized if Jeff Vinik had not moved here to buy the Tampa Bay Lighting and plan his own nearby project.

They said the port's early plans to develop the waterfront go back more than a year and a half. Klug noted the project is part of the port's "master plan" it must create every seven years or so to update its strategy on how best to utilize the thousands of acres it controls.

Ajamil sees the project as a win-win. "The best thing to happen to Jeff Vinik is this project," he said. "And the best thing for this project is Jeff Vinik."

So far, Vinik's team seems to view the port project as a major complement to its own goals. When the port first unveiled its waterfront plan, Vinik's group told the Times that it looks forward to continued discussions with port leaders "to see where the projects might meld together into the best possible solution for Tampa's downtown waterfront."

One has to wonder, though, if the port's plan to create 9 million square feet of mixed-use space could flood a downtown market that also must absorb the additional expansion from other projects.

The port, of course, is not developing an upscale waterfront as public welfare. Miyagishima and Ramsfield stressed the private developers the port hopes to attract will be building on land leased from the port. Revenues from those leases will be funneled back to the port to help sustain its own investments in port services. "That is part of our fiduciary duty as port managers," Miyagishima said.

Port investments are substantial, Kancharla echoed, and can often run between $60 million and $100 million annually. "A new dock can run $40 million."

All of that is years away. For now, the port needs to finish its master plan, and formally agree on project details with the city and the area's taxing authority, the Channel District Community Redevelopment Agency.

Clearly, the immediate buzz about the port's project is over its two 75-story towers. That's exactly the stir Ajamil wanted. The towers are slender and would house only 450 residential units, which is of similar size to shorter but broader Channelside towers. The exact number of stories may depend on what the Federal Aviation Administration says about air safety.

"They could be 70 stories," says Ajamil, who has consulted in this area about the cruise ship industry and in St. Petersburg in 2011 when it was starting to consider a new pier.

Seventy-five-story towers sound tall, but already in Miami, where Ajamil works, at least two towers have been proposed with 80 stories.

It's hard to stay on the cutting edge.

"I originally planned them at 100 stories," Ajamil says of his Port Tampa Bay towers, laughing, "but backed off."