More than a foot of rain fell across New Hampshire, Massachusetts and southern Maine between Friday and Tuesday, with up to 17 inches in some places. Police reported a single fatality, a 59-year-old man whose body was found in a submerged car north of Boston.
Gov. Mitt Romney said the damage would reach tens of millions of dollars in Massachusetts alone. And more rain was forecast for the weekend.
But on Tuesday, the worst appeared to be over. In Maine, roads reopened and the threat against two dams on the Salmon Falls River eased.
In Methuen, Mass., state and federal engineers watched a granite dam in danger of collapse after it was reinforced with 5,000 sandbags.
CBS News correspondent Sharyn Alfonsi reports that a 2006 study by the American Society of Civil Engineers found the nation's dams are in disrepair and dangerous.
"The eventuality of all this is if we don't get a hold of it were going to see cascading failures and significant loss of life across the eastern United States," Scott Cahill, an engineer who specializes in dam repair, told Alfonsi.
Many property owners began cleaning up, although major rivers remained above flood stage.
Jeffrey Saba, 42, used a 20-foot canoe to inspect his swamped home in Lowell, Mass., near the swollen Merrimack River. The water flooded Saba's garage and rose past his deck, 10 feet off the ground. "I just canoed over a 6-foot fence," Saba said.
"We are up against a battle now," Saba said. "The next couple of days will be just a waiting game."
Water flooded the first floor of a nursing home in Lawrence, forcing officials to cut power to the place and evacuate 243 residents, many of whom emerged in wheelchairs and on stretchers, wrapped in white blankets and clutching oxygen masks.
"I think these people are suffering more than any others I've seen," said Romney, who watched as rescuers removed the residents using a plywood bridge laid over the floodwaters.
Paul Monayer, a financial planner, skipped work to fight the floodwaters swamping his basement in Methuen.
"For the past two days, every three or four hours I've pumped out 100 to 200 gallons," Monayer said.
In Haverhill, officials worked to repair a burst sewage pipe dumping tens of millions of gallons of waste per day into the Merrimack River. State environmental officials said that the sewage posed no immediate threat to public health, and that a temporary fix should be in place by Friday.
The heavy rains triggered the worst flooding in some areas since 1936, according to the National Weather Service. And even though the month is only half over, it already ranks as the wettest May on record in Concord, N.H., and Portland, Maine.
Scattered showers were forecast through the weekend, but the rains should be much lighter, said Charlie Foley, a meteorologist for the National Weather Service in Taunton.
Entire neighborhoods in Nashua, H.H., were sandbagged as firefighters rescued about a dozen people and their pets by boat. About 40 female inmates from a halfway house in Concord, N.H., were taken to higher ground because of a leaky dam.
Many of the 2,000 New Hampshire residents who had been evacuated from their homes along the Salmon Falls River were able to return home by Tuesday evening. Earlier in the day, the rain had stopped, and the sun came out for a short while.
Maine Gov. John Baldacci joined Peggy Fennelly as she walked inside her candy store in York to find soda bottles and supplies bobbing in the dark floodwaters. Her freezer had fallen over, and boxes of candies and chocolate were soggy and ruined.
"I started crying and he hugged me," said Fennelly, 73. "He said, `You're a strong lady and you'll make it.' "