THE $US 12.3bn Hudson Tunnel Project has achieved what is expected to be the final regulatory milestone for the project before construction, after the US Army Corps of Engineers granted a permit to allow construction of the tunnel and tracks.

The Section 404/10 permit allows the construction of a new double-track tunnel within the New Jersey Meadowlands and beneath the Hudson River, and is the last major federal approval process, allowing full construction on the project to begin once the necessary funding is in place.

The project also involves the refurbishment of the existing 111-year-old two-track North River Tunnel linking New York and New Jersey, and a major bottleneck on the North East Corridor linking Boston, New York and Washington DC. The third and final section of the Hudson Yards Concrete Casing will also be completed as part of the project.

New Jersey governor Mr Phil Murphy called the project the “single-largest critical infrastructure effort in the nation.” He said he was looking forward to working with Amtrak and the Biden administration on completing the project.

“The project will help support the economic prosperity of New York and the rest of the country for years to come,” said Ms Kathy Hochul, New York governor, “which is why we need to get this project right and get it moving,”

“The rapid pace of Federal approvals not only signals the tremendous coordination between different government agencies at the federal and state levels, but also the prioritisation of the Hudson Tunnel Project and its anticipated impact on the economic well-being of the North East Corridor and the entire nation,” said Amtrak commissioner and Gateway Development Corporation (GDC) vice chair Mr Anthony Coscia.

Subject to funding, it is hoped that construction could begin in 2023. The new tunnel is expected to cost $US 10.1bn and refurbishment of the existing tunnel will cost $US 2.2bn. A financial plan was submitted by the Gateway Program Project Partners at the end of August for the project.