Trains will once again roll through a New York subway tunnel that was severely damaged by Superstorm Sandy, taking in 27 million gallons of water. New York Gov. Andrew Cuomo and officials from the state-run Metropolitan Transportation Authority took a ride Sunday through the reconstructed Montague Tunnel linking Brooklyn and lower Manhattan . Nearly two years after Sandy stormed through, the $250 million job is finished — one month ahead of schedule and $60 million under budget, officials said. Service on the R train under the East River is to start Monday at 6 a.m. , with about 65,000 additional daily riders.

When Sandy hit the subway system, “the most extensive damage was this tunnel,” Cuomo said. The salty water that inundated the tunnel’s electrical systems was “a terrible combination,” Cuomo said. On Sunday, MTA Chairman Thomas Prendergast and the agency’s top engineers squeezed with the governor into a track inspection car. From the slow-moving car headed to Manhattan’s Whitehall Street station, the officials examined the illuminated new ducts carrying electrical cables and water-resistant signals. In addition, the pumping equipment has been upgraded to better deal with any future flooding in the century-old tunnel. “And not only was it reconstructed, but it was fortified in the reconstruction,” Cuomo said. The massive repairs — funded by the Federal Transit Administration — include 11,000 feet of new track, 30,000 feet of new concrete, 75,000 feet of power cable and 200,000 feet of communication cable. About 10,000 tons of concrete and debris had to be removed before work started 13 months ago. The governor praised the city’s forefathers for daring to dig under the East River with far less technology than is available now. “The spirit of that vision is what makes New York what New York is,” he said.