MIAMI (CBSMiami) -- The engineering gem that is the PortMiami Tunnel is poised to open by Memorial Day, just four years after construction began on the mile-long, four lane, twin tube built with the sweat equity of thousands of workers and a 3,000 ton drill named Harriett.
CBS4 News was provided an exclusive tour of the tunnel Thursday, as some 500 remaining workers put the finishing touches on the project that will provide 16,000 cars and trucks a day direct access to the port, without having to jam the streets of downtown Miami as they do now.
"This will be the safest tunnel in North America," declared Chris Hodgkins, vice-president of the firm managing the public/private consortium that made the $1 billion feat a reality in lightning quick time, compared to many other major public works projects.
The illuminated direction signs are erected in the tunnel, the overhead lights are on, electronic message boards are operating, the pavement is laid.
The payoff so far: Business directed to 430 local companies, jobs for 7,500 people - more than 80% of them local - and $350 million put in local pockets.
Nearly a hundred cameras will watch over every inch of the tunnel and be monitored 24-hours a day, seven days a week from a master control room.
"If a truck stops in the middle of the tunnel, if a pedestrian comes into the tunnel, if a bicycle comes into the tunnel, we will immediately dispatch our response team to handle the situation," Hodgkins said.
The tunnel is also lined with infra-red sensors that can detect a wide variety of potential problems and sound alarms alerting tunnel operators.
"As a truck approaches, we have sensors that will tell us if the truck is over height, and it will not be allowed to enter," Hodgkins said.
Fresh air will not be a concern. The tunnel is equipped with 44 jet fans - yes, jet fans - that will keep it cool and prevent any accumulation of toxic fumes or gasses.
In the event a fire should break out, a state of the art suppression system will immediately deploy.
"Our active fire system is not a sprinkler system, but a deluge system," Hodgkins said. "We suffocate the fire."
Hodgkins said in the unlikely event an evacuation is necessary, escape routes are everywhere.
"You are at all times no more than four hundred feet from an emergency exit," he said.
The towering concrete portals to the East and West ends of the tunnel are carved with various conjugations of the latin word navigas - to navigate - and they hold hardware that makes the tunnel hurricane proof.
Hurricane Sandy in 2012 flooded and closed all but one of the tunnels leading to New York's Manhattan Island.
That won't happen with the PortMiami Tunnel.
"We have fifty ton metal gates that come down and shut the tunnel and make it water tight," Hodgkins said.
There is considerable pride among those who made the marvel happen.
"Definitely, definitely. I'm proud to be part of it," said construction worker Gabriel Echevarria.
With the completion of the job, the jobs will be gone. The good news is the construction industry is rebounding.
"I'm sure I'll be able to find another job soon," Echevarria said, adding that the tunnel project has taught him unique skills that will be a "valuable addition" to his resume.
Larry Pfeil, an electrical worker, said the company he works for will immediately move on to another major project in Boca Raton that will guarantee him two years of work.
"Right now, things are picking up," Pfeil said. "We're getting a lot more jobs now and a lot more opportunities."
At least 75 full-time employees will stay on to maintain and operate the tunnel.
Perhaps the best part of the subterranean wonder?
"This is a tunnel that is going to come in on time and on budget," Hodgkins said. "That's a claim that many public works projects cannot make."
The tunnel is considered visionary.
"With cargo traffic expected to double in the next ten years, this means economic prosperity for our community," said Gus Pego, District Secretary for the Florida Department of Transportation.
More icing on the cake: The tunnel will be toll-free.
An issue yet to be resolved: What to name the tube. Some have suggested a contest to come up with a name more sexy or historic or region-appropriate than simply the PortMiami Tunnel.
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