WATSON ISLAND (CBSMiami) – Construction of the new $1 billion Port of Miami tunnel has taken a giant leap forward now that “Harriet”, the tunnel boring machine, is digging the first of two tunnels under Biscayne Bay.

“This is an exact business. This is engineering at its finest,” said Chris Hodgkins, the vice-president of Miami Access Tunnel. “We are now 10 feet in terms of excavation. This boring machine was named for Harriet Tubman, the founder of the Underground Railroad that helped people during the Civil War.”

READ MORE: Judge Ketanji Brown Jackson, Who Has South Florida Roots, Could Be Next Supreme Court Nominee

“We have high hopes for this massive project,” Hodgkins told CBS4’s Peter D’Oench. “We see this project employing some 2,700 people with 400 direct lines.”

Over the weekend, construction crews officially broke into the ground and installed three temporary tunnel segments. The first permanent tunnel lining segments are expected to be installed as early as next week. Harriet, which is four stories tall and as long as a football field, will continue boring over the next six months before breaking through on Dodge Island.

“It could be a bit longer,” said Hodgkins. “Maybe seven months. But that’s when we see the end of this aspect.”

READ MORE: Teen Driver Arrested In Deadly Hit And Run In Miami

Harrit will then be partly disassembled, turned around and re-assembled before boring out the separate return tunnel to Watson Island. The tunnel will consist of two tubes featuring two lanes each.

Tons of soil is expected to be excavated for the tunnel. More than 400,000 cubic yards of limestone rock and dirt was supposed to be hauled to a former landfill on Virginia Key.

The start of drilling was delayed by a Key Biscayne councilman who sent the state a letter erroneously suggesting the village was considering a legal challenge to the project due to environmental concerns. The legal letter, sent to the Florida Department of Environmental Protection, was later withdrawn.

When complete the tunnel will provide direct access between the Port of Miami and I-395 and I-95. The tunnel is also expected to improve traffic flow in downtown Miami by reducing the number of cargo trucks and cruise related vehicles on congested downtown streets.

MORE NEWS: Broward Sheriff's Union President Jeff Bell Fired After Internal Investigation Found Corrupt Practices

Construction is expected to be complete by May of 2014.

Peter D'Oench