Parts of the region's transportation systems sputtered back to life Tuesday even as government officials warned that full subway and railroad service could be weeks, if not months, away.
Commuters should prepare for a patchwork transit system in the days ahead, Gov. Andrew M. Cuomo said.
"I think rather than talking about restoration of the system, it's going to be more a conversation of restoration of parts of the system," Cuomo said at a news conference.
Many roads closed by Sandy reopened Tuesday, as did most bridges and tunnels. Some bus service was restored on Long Island and in the city.
But the question many commuters are asking -- how long before mass transit is fully restored -- went unanswered by government and transportation executives.
"I can say unequivocally that the MTA last night faced a disaster as devastating as it has ever faced in its history," said Metropolitan Transportation Authority chairman Joe Lhota. "Sandy wreaked havoc on the entire transportation system, the subways, the buses, Metro North and the Long Island Rail Road -- in every single borough of the city and in every single county of the MTA region."
Long Island Rail Road service remains suspended while the agency assesses damage. Crews started clearing debris from hundreds of miles of track across its 11 branches Tuesday, including more than a half dozen boats, a Jet Ski and three shipping containers on the rails just north of Long Beach Station.
Downed trees, wires and other debris must be removed before power can be restored to the third rail and signal system.
At the Island Park Station, motorists stopped to snap pictures of a boat and its wooden dock pressed up against the station platform.
"It's devastating," said Susan Druckman, 54, of Island Park, who commutes by train to her currency exchange job in Manhattan.
In the city, seven subway tunnels under the East River flooded, as did two LIRR tunnels the railroad uses to link Manhattan with Queens. Flooding forced the railroad to evacuate its West Side Yards. LIRR service to Penn Station will not start until power is restored to the tunnels, officials said.
The storm knocked out transit services throughout the region. Metro-North Railroad lost electric power from 59th Street to Croton-Harmon on the Hudson Line and east to New Haven, Conn., on the New Haven Line. New Jersey transit trains remained shut down.
Some of the most extreme damage was in lower Manhattan where several subway lines converge. The South Ferry station early Tuesday was filled with water from track to ceiling, as were several of the subway tunnels. The water began receding later in the day, MTA officials said.
"We are in the process of pumping water out of the East River tubes and some of the affected tunnels," said Kevin Ortiz, an MTA spokesman.
Cuomo toured Ground Zero in lower Manhattan, surveying flooded PATH rail system tubes and the Brooklyn-Battery Tunnel. He called Monday night's storm surge "frightening."
"It was unbelievable last night how much water was coming into this site," he said, standing beside One World Trade Center, which is under construction.
Officials plan to use buses to fill gaps as piecemeal restoration of the subway system begins.
Bloomberg also signed an order allowing the 4,000 yellow cabs in the city to pick up multiple passengers and livery cabs to pick up street customers.
All major bridges connecting Long Island opened Tuesday, including the Robert F. Kennedy, Verrazano-Narrows, Bronx-Whitestone, Throgs Neck and Henry Hudson bridges.
But floodwaters kept the Hugh L. Carey -- formerly the Brooklyn-Battery -- and Queens-Midtown tunnels closed.
George Kern, director of bridges and tunnels for the New York City Department of Transportation, said damage assessment alone could last until Monday. He estimated water filled the mile-long Carey tunnel 18 feet deep and flooded an area from the FDR Drive to West Street, Kern said.
In Suffolk County, Department of Public Works Commissioner Gil Anderson said the highways "are in pretty good shape -- except for traffic signal problems." But some local roads looked like "a war zone," he said.
Signs of recovery grew throughout the day Tuesday.
The MTA restored partial bus service -- without charging fares -- in time for the evening rush. Full bus service was likely Wednesday, officials said.
Limited NICE bus service started in Nassau County Tuesday, also without fares. The N4 and N6 routes started running on a Sunday schedule; other routes are to start Wednesday.
Suffolk County Transit service, including all of its Suffolk County Accessible Transportation services, will stay suspended indefinitely.
Efforts to restore service at the region's airports were mixed. Cuomo said airlines would start flying at Kennedy Airport Wednesday, although service would be limited. LaGuardia Airport is to remain closed because of "extensive damage," which included flooding on a runway, he said.
Ron Marsico, a spokesman for the Port Authority of New York and New Jersey, said airport officials would conduct damage assessment at LaGuardia "in a deliberate and safe fashion."
Long Island MacArthur Airport officials said Southwest Airlines would return to flying at the Ronkonkoma facility this morning. US Airways plans to resume flights Thursday at noon, airport officials said.