YBOR CITY — Demolition work Tuesday unearthed the first new opening in 20 years to the old brick tunnels that serve as a reminder of Ybor City's smuggling past.

But this one stirs new debate about the Latin District's underground pathways, in part because it doesn't appear it could ever have served the legal origin often ascribed to the tunnels — as a system of drainage into the Ybor Channel and Tampa Bay.

Tearing down a warehouse at 12th Street and Sixth Avenue revealed a brick-lined tunnel tall enough to walk through with rounded ceilings and walls but a flat floor of dirt.

That would never work as a drainage way, which would be round, said Gerry Curts, whose Curts Gaines Hall Jones Architects adjoins the demolition site.

"If you are going to build drainage why would you do it like that?" Curts said.

Historians have theorized that because of the time, money and manpower required to create the tunnels, they may have been designed as a public works project and later exploited by Tampa's organized crime syndicate in the early 1900s to smuggle moonshine, lottery numbers and people.

RELATED: From bunkers to tunnels, Mafia history stirs underworld exploration in Ybor City

Rodney Kite-Powell, curator at the Tampa Bay History Center, has refrained from endorsing the theory that the tunnels were smuggling routes but said the new discovery adds some credence to it.

"The dirt floor would make the drainage theory much less viable," Kite-Powell said. "But I'd like to know that there isn't brick under the dirt."

The demolition property, Curts said, is owned by the Darryl Shaw and Joe Capitano investment group, which has many parcels in Ybor City including the site of a proposed new stadium for the Tampa Bay Rays.

RELATED: Sixty years ago, a bolita operator was gunned down and the mob firmed its hold on Tampa

According to the Ybor City Development Corp., an office project is planned at the site but the developers could not be reached for comment.

The tunnel is part of the same system uncovered in the early 2000s when tracks were placed for the TECO Line Streetcar System at the same corner, Curts said. He has long suspected the tunnel stretched beneath the warehouse so when he heard the building came down yesterday, he rushed over to see for himself.

RELATED: Trafficante featured in new tour linking Tampa's, Havana's Mafia past

The tunnel extends toward the Ybor Channel but Curts said it is hard to estimate how far.

If the tunnel reaches the water, that adds credence to a theory that historian Gary Mormino has heard about using the path for smuggling in Chinese immigrants from the 1880s through the 1920s when laws made it almost impossible for Asians to come to the United States

A separate tunnel system once lay beneath the site of the old Blue Ribbon Grocery Store at 14th Street and Seventh Avenue, providing a possible connection for running moonshine and lottery numbers to and from the old Las Novedades restaurant, some historians have said.

A fire destroyed the building and tunnels in 2000 before it could be more fully explored.

Contact Paul Guzzo at pguzzo@tampabay.com or follow @PGuzzoTimes.