Canadians are helping restore power to parts of the U.S. ravaged by superstorm Sandy.

A southwestern Ontario crew of 14, comprised of power line workers from Essex Power Lines, Entegrus Power and Erie Thames Power, is among the volunteers in New Jersey.

The crew is restoring electricity to 800,000 customers in Flemington, N.J.

'It's complete devastation.' — Gary Aitken, Entegrus Power

The group arrived last week, days after the storm passed through. They have restored power to less than half the nearly 1 million customers affected in the rural area of New Jersey.

"It’s complete devastation," Entegrus power line worker Gary Aitken told CBC News from Flemington Monday.

Aitken said 500,000 people in the area are still without power. He and his crew are working 16-hour days, the maximum allowed under the law. They start at 6 a.m. and end at 10 p.m.

"By the time we get back to the hotel, we’re pretty tired," Aitken said.

Aitken said once power is restored by a Canadian crew, customers slap a "Thank you, Canada" sign on their mailboxes.

"The reception has been unbelievable. The people were unbelievable to us. They can’t believe people all the way from Ontario are here to help," Aitken said. "It’s pretty overwhelming."

Aitken said he planned to be in the area for 10 days, but may end up staying two weeks.

New Jersey state officials report there are still 833,000 power outages in the state. That's down from 2.7 million. The multistate volunteer effort is being called the biggest power recovery effort in U.S. history.

More than 5,000 linemen are in the region. They have come from as far away as California. Hydro One sent 145 employees.

Meanwhile, an ENWIN Utilities relief crew of six employees and four vehicles left Windsor, Ont., for Long Island on Monday. The workers from Windsor will provide assistance to Long Island Power Authority restoring power to those affected by Sandy.

Not first volunteer effort

Aitken has previously volunteered in the U.S., after hurricanes struck Texas and Louisiana.

"We have to get the power on for the people to make them happy. That’s what the power line maintainers do," he said.

This latest relief effort differs from previous ones, Aitken said. He said workers are dealing with many more "hangers" — trees that are broken, but not fallen. Workers are also on the edge of mountainous terrain, and a Nor’easter storm is predicted to bring snow to the region as early as Tuesday.

Monday, temperatures were slightly above freezing.

"This was a different hurricane. It looks like a bunch of mini-twisters hit the area," Aitken said. "And with snow that’s predicted, we may have more issues."

The new storm worried the large swaths of the region that were returning to something resembling normal.

"Prepare for more outages," said National Weather Service meteorologist Joe Pollina. "Stay indoors. Stock up again."

With files from Associated Press