It's the official groundbreaking for the Hudson Yards Right of Way project.
New flood-proof tunnels are being built to help expand rail capacity, with an 800-foot-long casing between 10th and 11th avenues.
Officials say $185 million in Hurricane Sandy relief funds are financing the project.
Senators Charles Schumer and Robert Menendez, Congressman Jerrold Nadler and Amtrak Chairman Tony Coscia will attend.
