National Weather Service meteorologist Mitchell Gaines said Monday that the river crested at 25.15 feet at Easton and was slowly falling lower - it was at 24.71 feet by 11 a.m.
By 11:30 a.m., the river was at 24.71 feet in Easton, below the 26-foot moderate flood stage. It's expected to drop below the 20-foot flood stage early Tuesday morning.
The river, which meanders between Pennsylvania and New Jersey, is forecast to continue dropping through the day to normal levels on Tuesday. The river had initially been forecast to go higher than 30 feet.
"I'm sure everyone is ready for this flooding to be over with," said Lee Roberts, another meteorologist.
Helen Hunter, who lives along the Lehigh River, near its convergence with the Delaware in Easton, was among those who evacuated, staying at a hotel Sunday night along with her daughter and two sons.
Hunter, 82, opted for a hotel, expecting her home to flood like it did in 2004, 2005 and 2006.
`I was disgusted. I said, `I'm getting tired of this, year after year,"' said Hunter, who returned to find the Lehigh swollen but the road only covered in a few spots.
"It's looking good right now," she said as she prepared to move her belongings back to the first floor. "It's really looking good."
Across the state, 443,000 customers remained without power Monday, according to Ruth Miller, a spokeswoman for the Pennsylvania Emergency Management Agency, down from what had been 706,000.
Philadelphia International Airport, which closed to traffic during the storm, was starting to resume service Monday. Flights started arriving again late Sunday night and early Monday, airport spokeswoman Victoria Lupica said, and most carriers expected to return to a regular schedule by Monday afternoon.
The mass transit agency serving Philadelphia and its suburbs, which also suspended service during the storm, was working on returning to a normal schedule Monday, spokesman Andrew Busch said.
All of the Southeastern Pennsylvania Transportation Authority's bus, subway and trolley lines were running, Busch said, but service on four of the 13 regional rail lines remained suspended.
In several school districts, where the new academic year was scheduled to begin Monday, classes were canceled because of Irene. Among the districts postponing the start of the school year until Tuesday were Easton, Central Bucks, Coatesville, Kutztown, Nazareth and Unionville-Chadds Ford.
On Sunday it was the Schuylkill, that wreaked havoc, cresting to more than 15 feet in Norristown and inundating homes with muddy water and flooding streets in Philadelphia, too.
"You take the good with the bad down here," said Bud Buono, 51, who's lived on the Schuylkill for 30 years. "It's a different breed of people."
In Philadelphia, the Schuylkill flooded low-lying streets and crested at 13.56 feet just after 2 p.m. - below the 15-foot level that city officials had forecast.
Irene has contributed to at least five deaths in Pennsylvania and left hundreds of thousands of Pennsylvania customers in the dark.
Though the skies cleared Sunday - the sun was out on Monday, too - the lingering concern remained complacency amid the cleanup.
"We have been very fortunate to this point," Gov. Tom Corbett said at a news conference Sunday. "Even though it's clearing up out there, we're not done yet."
Eleven Pennsylvania counties are on the list for potential federal disaster assistance, and officials say more counties may be added as the state recovers from Hurricane Irene.
The Pennsylvania Emergency Management Agency said Monday the list so far includes Bucks, Chester, Delaware, Lehigh, Monroe, Montgomery, Northampton, Philadelphia, Pike, Wyoming and Wayne counties.
Associated Press writers Patrick Walters in Philadelphia and Peter Jackson in Harrisburg contributed to this report.