Maurice Ferre served as the mayor of Miami from 1973 to 1985. During that time, his administration noticed that the Brickell Bridge, which spans the Miami River downtown, had been mucking up traffic on Biscayne Boulevard. The structure is a drawbridge, and every time a boat passed into the bay, traffic on both sides of U.S. 1 ground to a halt. So Ferre's administration proposed digging a tunnel under the river.

But Ferre's fellow city officials shot down the idea down. And in the decades since, traffic around the bridge has gone from bad to a recurring nightmare as searingly painful as having your liver repeatedly torn out by an eagle every single day just like Prometheus." It's bad.

So, with a whole host of new residential projects about to open in Brickell, Miami Commissioner Francis Suarez is mounting a campaign to get the city or the state to finally dig that tunnel under the river.

"I know it's been pitched in the past multiple times," Suarez says. "But now the density in the city has never been greater. And we've reached a breaking point in Brickell."

In 2015, the Miami Commission, at Suarez's request, ordered a study of whether a tunnel could replace the much-despised bridge intersection. Now the study is finally complete, and armed with new information, Suarez has spent the first few months of 2017 speaking to various city boards in an attempt to drum up support for the plan. In January, Miami's Downtown Development Authority threw its support behind the project. And earlier this month, the Miami River Commission also endorsed the idea.

Suarez says the city estimates the four-lane project could cost $850 million. But he contends people in the private sector, "Elon Musk types," have suggested the tunnel could built for just $250 million.

U.S. 1, however, is a state road, which means Suarez's best shot at getting a tunnel built is to lobby the Florida Department of Transportation to place the project on its five-year plan.

Suarez says he'd like to lobby FDOT to approve the plan or place the project up for competitive bidding at the city level as soon as possible. He lists seven new skyscrapers set to be built near the already-clogged intersection, including Miami Worldcenter and the project at 600 and 700 Biscayne Blvd.

"There's going to be a tremendous amount of potential growth to this 'clogged heart' of an intersection," Suarez says. "Part of our analysis uncovered that most of the traffic at that intersection flows through the heart, not to the heart. It's mostly people who want to get to other parts of town. In making the tunnel, using that medical analogy, we'd be bypassing the clogged heart."

Suarez says the city's study shows that every time the drawbridge goes up and stops traffic (which happens multiple times per day), city businesses lose roughly $40,000 in revenue. Downtown Miami alone accounts for roughly 5 percent of the total economic output for the entire state, so he thinks it would make simple sense for FDOT to fund the tunnel project.

"Brickell is at its breaking point," he says. "If we just further exacerbate the breaking point, people are going to start making investment decisions based on that," and it'll drive potential investors out of the neighborhood.

The idea of a tunnel isn't unprecedented: Miami-Dade County finished drilling a tunnel from the mainland to PortMiami in 2016. A tunnel-boring machine nicknamed "Harriet" dug for two years. But after that passageway was complete, Harriet left town. A new tunnel project would take years of planning and legwork. Boring through the porous, wet limestone won't be easy.

Miami River Commission Chair Horacio Stuart Aguirre, however, says it's pretty much now-or-never to get the idea off the ground.

"It’s a shame it hasn’t been done in prior decades," he says. "It would have cost a fraction of what it will eventually cost." He says Mayor Ferre employed an engineer named Vijay Varki, who warned decades ago that the bridge would eventually create a nightmarish bottleneck. But city commissioners at the time punted on the project because they thought it would cost too much.

"It shouldhave been done 25 years ago," Aguirre says, "but they wanted to be cheap. 'Cheap' turns out to be expensive in life."

• Traffic