It’s going to be a complex task to bore a train tunnel beneath North Bergen, through the sturdy Palisades Cliffs, under Union City, near the Weehawken border, below the Hudson River, and all the way to a train station in Manhattan.
But next month, work will begin on the first step in the project, a railroad line underpass that will run beneath Tonnelle Avenue to connect to a tunnel through the Palisades hills.
The railroad may even have to take a piece of property at the northwestern end of Hoboken, near the Weehawken border.
On May 13, the NJ Transit Board of Directors unanimously approved a $13.6 million contract with Ferreira Construction Co. Inc. of Branchburg to begin building the underpass. The company will also construct a new railroad embankment west of Tonnelle Avenue to carry the rail line.
The complete train project, referred to as Access to the Region’s Core, or ARC, is expected to cost $8.7 billion by the time it is finished in 2017. By 2030, it should more than double the number of trains that can travel between New Jersey and New York City from the current 23 per hour to 48.
Ferreira Construction is the first of an expected two dozen or more contractors, with many sub-contractors beneath them. The project will be choreographed among a projected 6,000 workers.
The underpass portion of the project – a rail line under Tonnelle Avenue – is slated to be complete in 2012.
The new tunnel will be built next to an existing pair of tunnels through the Palisades that were dug more than 100 years ago by the Pennsylvania Railroad. The existing tunnels run through the Palisades and are currently part of the Northeast Corridor line operated by Amtrak, leading to Penn Station in Manhattan.
“We’re at about the same elevation of the existing 100-year-old tunnel system and wind up at the foothill of the mountain [of the Palisades Cliffs], and that is why it was chosen, which is exactly the same reason it was chosen 100 years ago,” said Chief of the Trans-Hudson Express Tunnel Project Arthur Silber. “The mountain hasn’t moved.”
NJ Transit and the Port Authority of New York and New Jersey have committed $5.7 billion to the ARC project, with the remaining $3 billion being sought from the federal government. Last week NJ Transit received news that an additional $200 million of the administration’s fiscal 2010 budget was set aside for the project, bringing the government’s total funding commitment to nearly $378 million.
Digging through
According to Silber, when construction hits its stride, there will be eight to 10 contractors working on the new tunnel at the same time. Different contractors will be responsible for a 5,000-foot portion of the tunnel from North Bergen to Hoboken, and another contractor will dig through the Hudson River muck for 7,000 feet until reaching Manhattan.
In Manhattan, yet another company will construct the tunnel to the train platform, where yet another contractor will take over.
Machine will head underground from NB to Hob
A custom-built tunnel boring machine, electrically powered with wheels made of steel alloy, will advance through the Palisades from North Bergen to a shaft in Hoboken at about 30 to 50 feet a day, at anywhere from 186 to 270 feet below ground, said Silber.
The new tunnel will run under portions of North Bergen, Union City, and Hoboken. Silber said that the rock of the Palisades is mostly diabase – a hard, tough rock sometimes commercially known as “black granite” – and is “some of the best rock that a tunneler could only dream about.”
Some property owners in the affected towns will be compensated for any rock removed from part of their land. Silber said the owners will receive just compensation.
“When you own property in America, you own to the center of the Earth and to the stars, and that’s called your bundle of rights,” said Silber.
For those concerned about blasting, Silber said there will be some controlled blasting, but it will be far different from what occurred 100 years ago. Blasting will only be used to create the emergency exit passageways between the two tunnels and for other areas that boring machines will not be able to reach. The entrance to the tunnel system from Tonnelle will be blasted just so that there can be a “smooth face” for an entrance.
“At worst, it’s like a truck going in front of your house,” said Silber.
Hoboken air shaft
The boring machine will take several months to dig through the Palisades until it reaches the border of Hoboken and Weehawken, where it will be lifted out of an air shaft and brought back around to make the second tunnel.
This same shaft will be used as an entrance for the machinery that will create the tunnels beneath the Hudson River.
Silber said that he believed the machinery will be an earth pressure balance machine, a boring machine that stops soft clay from collapsing.
Later on, the shaft will become the tunnel’s vent plant, where fans will be turned on in the case of an emergency and once a month as maintenance.
The current property at the location is a jitney bus repair shop, said Silber.
Avoiding hazards
Silber said that the design of the tunnel had to be meticulously planned because of the existing 100-year-old tunnel nearby. The new tunnel will be about 50 feet below where the Pennsylvania Railroad tunnels lie. The Pennsylvania tunnel, currently operated by Amtrak, was built very close to the bottom of the water and the top of the mud line, said Silber.
“If we build [a tunnel] right next to it, it may move,” said Silber.
For this reason, the tunnel will head south beneath the Hudson River, before heading North to Manhattan.
Silber also wanted to be far below the water’s surface because he wanted to avoid disturbing water currents and the Hudson River as a whole.
“Back then, there was no such thing as river pollution and there was no such thing as Army Corps. of Engineer permits and there was no such thing as environmental conservation or protection,” said Silber. “You built what you built and the world went on.”
Read more about the other facets of the ARC project in next week’s Reporter.
Tricia Tirella may be reached at TriciaT@hudsonreporter.com.