Jointly sponsored by New Jersey Transit and the Port Authority of New York and New Jersey, the new rail tunnel will be the first to be built under the Hudson River in nearly a century and is expected to support 6,000 construction jobs annually. Originally conceived with the idea of eventually linking Penn Station and Grand Central Terminals, the project now will comprise a new trans-Hudson tunnel leading to a separate NJT rail facility to be built 175 feet below street level at 34th Street, unconnected to Penn Station trackage, according to NJT documents.

In a release, Port Authority chairman Anthony Coscia calls the ARC tunnel a "once-in-a-generation project that will remake transportation between New York and New Jersey." He says the commission's vote brings the project "one step closer to a new mass transit tunnel that will remove cars from our congested local roads, improve the air we breathe and create thousands of much-needed jobs in the near term."

The Port Authority has committed $3 billion in funding, with the balance coming from NJT and federal sources. In a separate but related project, NJT will construct a new portal bridge over the Hackensack River at an estimated cost of $1.3 billion. Work on the two projects is expected to take about 10 years.