Death toll from the disaster rose to 70 deaths in the United States, including 24 in New York City, 8 in New Jersey and 4 in Connecticut as rescue workers pulled bodies from wreckage across the region, according to the New York Times
New York Governor Andrew M. Cuomo said initial damage estimates "project up to $6 billion in lost economic revenue" in the State.
A wide stretch of Lower Manhattan remained dark, as did the Jersey Shore, waterfront neighbourhoods in Brooklyn and Queens, and most of Long Island.
Touring battered New Jersey with the state's Republican governor Chris Christie, who has been all praise for President Barack Obama's handling of the situation, Obama promised the federal government "will not quit" until communities are cleaned up, according to CNN.
"We are not going to tolerate red tape, we are not going to tolerate bureaucracy," Obama said. "And I've instituted a 15-minute rule, essentially, on my team. You return everybody's phone calls in 15 minutes, whether it's the mayors, the governors, county officials.
"If they need something, we figure out a way to say yes."
Some 10,000 Army and Air National Guard forces were on duty in the 13 states affected by the storm.
Mass transit was still in disarray. Most buses were running in New York City, and some subway lines were due to open Thursday. Most of New Jersey's statewide bus service will be restored Thursday, Christie's office announced, though most rail lines will still be closed.
Two New York-area airports-John F. Kennedy and Newark Liberty-reopened Wednesday with limited service. LaGuardia Airport, where floodwaters had covered runways and taxiways, will reopen with limited service Thursday morning, the Port Authority of New York and New Jersey said.
The Lincoln Tunnel was open, but the Holland Tunnel, the other tunnel connecting New York and New Jersey, was still full of water. The Port Authority said it can't start pumping out the water until power is restored.
About 2.2 million homes and businesses in New Jersey are still without power tonight, utility officials said. Jersey Central Power & Light reports 940,000 outages and Atlantic City Electric was down to 107,000, according to New Jersey Star Ledger.