It seemed as if they had been spared. And then in minutes, the flood came, and it did not come from the skies.

Hurricane Sandy swept through this low-lying industrial town 10 miles northwest of Manhattan on Monday night with high winds and some rain, but with far less damage than people here expected. Many still had power.

And then about 10:30 p.m., water began to gush out of storm drains and down streets. Within minutes, it was ankle-deep. It lapped furiously at basements and front steps. It crept to the bottom of first-floor windows. The giant wheels on the town’s fleet of firetrucks were submerged. Within 45 minutes, Moonachie was under five feet of water.

“It happened so fast,” said Nancy Perez, wearing tall boots as she surveyed the river outside her small ranch house. “I mean, it was totally out of the blue.”

The hurricane triggered a tidal-storm surge in the Hackensack River, sending water over a riverbank and swamping Moonachie and neighboring Little Ferry so quickly that startled residents didn’t know what happened.

“It was fountains coming out of the street,” Curt DeChert said. “You could blink your eye — that’s how fast it was.”

Gov. Chris Christie (R) described the sudden flood as a “natural berm overwhelmed by an unprecedented tidal surge.”

This community of 2,700 next to the New Jersey Meadowlands was left its own anxious and isolated island, with roads blocked off well into Tuesday night. A frantic, middle-of-the night rescue that started Monday continued into Tuesday afternoon, though some residents decided to stay put.

“We were talking about how lucky we were” to be spared the worst of the hurricane, Bolwinder Singh said while waiting with his sister-in-saw to be taken to a school gym. “Then I saw a ripple out of the corner of my eye. Then a wave came four or five feet high.” The water crept up his basement stairs. “An inch more, and it would get to the house.”

His neighbor, holding a frightened white Maltese named Jersey, was trying desperately to reach her elderly parents, who had been taken to a shelter in the first round of rescues.

The day after the flood, cars abandoned on the town’s main street seemed to float. Firetrucks and National Guard trucks crawled along, looking for stranded residents. The parking lot of an adult movie store was gone, as were the police and fire department buildings. The first responders had to relocate to a neighboring town.

Downed power lines dangled close to the water. A fleet of red 18-wheelers stored in the parking lot of a Coca-Cola distributor looked suspended in the air, their wheels invisible.

Emergency workers tried to shovel the foot of water covering the floor of Little Ferry Borough Hall with the only tools they had: a dustpan, which they used to pour water into giant garbage bags.

“We were using little cups before we found the dustpan,” said Samantha Boustani, remaining cheery. Little Ferry had begun to flood from a nearby creek after Sandy came through — but slowly. “Then Moonachie’s problem turned into our problem,” said Steve Tedesco, who works for the local public -works department.

A resident who had decided to stay came in looking for his dog, who had escaped from his back yard when high winds tore a hole in his fence.

Borough Hall had briefly served as a shelter for stranded residents Tuesday morning after a church around the corner flooded. Then Borough Hall lost power and a dry floor, and it had to be evacuated, too.

As the asphalt pavement disappeared, the best way to get around was by boat. , and rescue crews put many in the water.

Scott Lemongello, a 25-year-old Moonachie police officer, rowed his bright-orange canoe to the town’s main street about 2 p.m. He said he had to get out of his house, where water was “up to the handle of my door.” Everyone on his block had been taken to shelters. Technically, he was off-duty, but in the previous 12 hours, he had gotten his elderly neighbor across the street who was yelling for help to safety and rowed his brother to Little Ferry to check on his house.

Lemongello lives with his parents, who wanted to stay put because they feared being separated from their two dogs. He was wearing black thongs and a black raincoat. He was 5 in 1992 when Hurricane Andrew hit his community. He still remembers it.

“That was nothing like this,” he said. “My house looks like a scene from the Titanic.”