Workers on the mammoth Gateway tunnel project are getting ready to start drilling through the Palisades in the new year.
The Gateway Development Commission — the public authority behind the construction of the new Hudson River tunnel projects — said the first of two tunnel boring machines will arrive in January.
The machines were purchased as part of a nearly $465 million contract. They’ll dig through rock in the Palisades, below North Bergen and Union City. It will take months to mobilize and test the boring machines, which are each about 28 feet in diameter, 500 feet long and weigh 1,700 tons.
They will be set up about 50 feet apart and drill about 27 feet of tunnel a day.
“These [machines] are not standard construction equipment. They are massive, highly complex machines that have been custom-built for the Hudson Tunnel Project,” Gateway CEO Thomas Prendergast said in a statement. “Producing them is an impressive feat in and of itself.”
A bird's-eye view of where the boring machine will begin drilling into the earth.
The boring machines were manufactured in Germany for just one of 10 sections that make up the $16 billion Gateway project to build a new tube for Amtrak and NJ Transit trains into Penn Station. The existing 115-year-old tube, which was damaged by Hurricane Sandy, will also be repaired.
The tunnel is a critical choke point for Northeast Corridor train service.
The machines are made by German manufacturer Herrenknecht, the same company the MTA tapped to build its own tunnel boring machine to dig out the Q line extension of the Second Avenue Subway in East Harlem.
Gateway’s machine will dig the earth and line the concrete tunnel sequentially. The boring machine used to build the Second Avenue Subway machine digs and lines the tunnel simultaneously – a feature that MTA officials said allowed them to use fewer workers.
Hamed Nejad, Gateway’s chief engineer for the project, said each boring machine will dig a single tunnel in a roughly 1 mile section.
“We’re going through a very hard rock,” Nejad said. “And therefore, because of the geotechnical condition of the job, it was determined to use two single-shield hard rock machines for this project to excavate.”
A single-shield tunnel boring machine is designed to cut through rock and other dry earth. A different boring machine will be manufactured for the mixed ground conditions beneath the Hudson River.
Gateway is the largest public works project in the country. It’s a different construction approach from the original Hudson River project, where crews employed techniques such as drilling by hand, using explosives and pumping compressed air underground to build the tunnels.
President Donald Trump vowed to “terminate” federal funding for the Gateway project during the federal government shutdown earlier this year. The move was seen as a dig at Senate Minority Leader Chuck Schumer, a New York Democrat who has backed the project for years. Work on the project continued and the federal government says the funding remains “under review.”
