The New York Metropolitan Transportation Authority (MTA) approved a $17.1 million contract with a marine firm to bolster underwater subway tunnels with layers of concrete and dirt to stop flooding from a bomb blast.
According to the Daily News, officials wouldn't provide details of the project for security reasons.
The MTA has 14 underwater subway tunnels, most of which are dug through solid rock.
The agency also approved $80 million to add 399 surveillance cameras and 425 motion sensors to the system to thwart terror attacks.
That work expands a $212 million contract awarded to Lockheed Martin last year to install 1,000 cameras and 3,000 sensors across its network.
The underwater tunnel reinforcement contract is with Spearin, Preston and Burrows Inc.