As a freight train plunges into the more than century old Howard Street Tunnel by Camden Yards on the south end, it pushes air through the 1.7 mile long tube creating a zephyr on the other end.
It’s enough to ruffle the ivy along the tunnel wall at Mount Royal Station; its gentle breeze hits the face followed shortly by the distant sound of the train's horn hitting the ear.
In about 5 minutes, the CSX train will amble and sway nearly nine thousand feet underneath Baltimore's West side eventually bursting out and past the old Mount Royal station on its way through the city to the Port of Baltimore.
The Howard Street Tunnel is still mostly the only way freight gets through the mid-Atlantic - antiquated and impressive all the same.
"This is 121 years old so this really does go back to the early ages of the B&O railroad so it's a great piece of history here," Louis Renjel, CSX vice president of strategic infrastructure said.
He gets wrapped up in the history of this old underground throughway, but he knows it's one of the oldest tunnels in the country and its history needs a revision.
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"The modern most efficient way to move goods now is by double stack clearing which is taking two of the tractor trailer containers you see every day on 95 and stacking one onto another and the only way to do that is increasing the clearance to this tunnel," Renjel said.
While the structural integrity of the tunnel, amazingly enough, is still sound its clearance is simply too low to meet the amount of freight CSX would like to get from and to the Port of Baltimore.
It's been an issue for years. The original plan was to dig up and replace the structure at a cost between one CSX realized last year it could be done a different way, by simply shaving off the ceiling or digging out the floor to get the clearance it needs.
It is a newer method that costs significantly less at $425 million.
[What are we looking for here?] “We are looking to increase the vertical clearance by a foot.
[Just one foot?] “One foot," Renjel repeated.
That foot is the port's Achilles heel said executive director of the Maryland Port Administration James White.
Retrofitting the tunnel to fit double stack trains will immediately grow what the industry already ranks as the most efficient port in the country.
In recent years, deep water berths and new giant cranes have helped, but progress continues to hit its head on a ceiling just one or two feet short.
“The container business is the biggest job producer per ton than any of the other cargos we handle and we feel that with the double stack, if we are moderately successful at it, we can grow out another 6000 direct jobs," White said.
From atop the newer, bigger cranes, you can see how. Right now the cans are loaded on trains one at a time and run through the tunnel, doubling that would rev up an economic engine Governor Larry Hogan thinks is a game changer.
"The port is responsible for $51 billion a year to our economy and this could dramatically increase the production of the port. Quite frankly I think it is transformative, not only to the port of Baltimore but Maryland's economy in general," the Governor said.
It is why after touring the tunnel late last summer, Hogan recommitted $145 million from the state budget to match CSX's $125 million.
What remains is $155 million from the federal government.
It was a grant that was denied late last year, a setback for a transportation project the state feels was tailor made for the federal program.
Still, Hogan recommitted and insists they will try again this year.
"We are going to submit again. We believe that we will be successful this time. We've got a commitment from the state and from CSX already to make sure this thing can happen and make it a reality. Now we just need the feds to come through," the governor said.
And if they do, it could shatter a 120-year-old stone ceiling leaders feel is holding Baltimore back.
If approved, the Howard Street Tunnel clearance project would take CSX four to five years to complete. During the work, the tunnel will remain operational, passing 25 trains every day.
Hogan has addressed the need for the federal money last year with vice president Joe Biden. He has spoken with vice president Mike Pence about Maryland's infrastructure projects and the importance of the federal grant for the Howard Street Tunnel project.