A $6.8 billion federal grant approved last week allows the Gateway Development Commission to start awarding construction contracts to begin work boring the tunnels either late this summer or in early fall.
That is the most money ever provided to a mass transit infrastructure project in the nation.
Once the deal got the green light Monday, federal officials believe it passes the "point of no return" and cannot be reversed.
"After many false starts and obstacles placed in our way, Gateway is full speed ahead with billions from FTA ready to go and be used for critical work and construction," said Sen. Charles Schumer. "Gateway's future is assured and the most important public works project in America is all systems go."
The long-delayed tunnel between New Jersey and Penn Station in Midtown may not be completed until 2035. When it is, it will provide extra capacity and reliability for NJ Transit and Amtrak trains beset by delays on that stretch of the Northeast Corridor.
The existing pair of single-track tunnels is more than 110 years old and suffering from damage sustained by flooding during Superstorm Sandy in 2012.
This is take two. In 2010 before Sandy, work had begun for a different rail tunnel under the Hudson -- but before signing a similar funding agreement with the federal government, then-Gov. Chris Christie canceled the project and said New Jerseyans were shouldering too much of the burden.
Donald Trump also denied funding when he was in office.
"Ever since Governor Christie pulled out the funds, I knew we had to do something, there were lots of twists and turns, Donald Trump said you build a wall maybe I'll give you gateway, I told him NFW, we're gonna get this done on our own," Schumer said.
Hochul and Schumer say the federal government is picking up the tab for about 70% of the total cost -- $1 billion of that is coming from Amtrak, which owns the existing tunnels and Penn Station.
The balance and any overruns will be paid for by New York and New Jersey.
"After decades of delays, the Gateway Hudson Tunnel Project is finally moving forward. This Full Funding Grant Agreement will provide the critical resources needed to deliver an essential piece of infrastructure that will bring millions of visitors to New York every year," Hochul said.
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