The Red River began cresting here Tuesday afternoon, just over two feet shy of the 1997 flood, the city's worst in a century.

The river, which runs north along the North Dakota-Minnesota line, was peaking in Fargo at 37 feet, or 19 feet above flood stage, about 5 p.m.

Swollen with melting snow and heavy rain, the river has spread across its broad valley, leaving farm land under water and city residents stacking sandbags.

"It's at crest, but that crest is going to take several hours," said Greg Gust, a meteorologist with the National Weather Service in Grand Forks.

The U.S. Army Corps of Engineers said it had finished with emergency levee construction in Fargo, and engineers planned to walk the dikes late Tuesday and into Wednesday morning to ensure their stability.

More than 660 students from three Fargo high schools joined the sandbagging effort on Monday. Volunteers of all ages came out to fight the flood waters.

Cass County's emergency manager, Dave Rogness, said the sheriff's department was sending boats to rural areas to check on people. Gov. John Hoeven flew over the Red River Valley earlier in the day.

"Right now, it's a lake. I mean, it just spread out. There's a lot of water," Hoeven said.

Across the river, about a dozen homes north of Moorhead, Minn., were surrounded by water and residents were using boats to get supplies, Minnesota Gov. Tim Pawlenty said. He said officials were watching to see whether the entire Oakport Township became an island.

"We've got contingency plans if that happens," Pawlenty said during a stop in Moorhead.

The weather service expects the Red River to crest in the Grand Forks area, about 70 miles north of Fargo, at about 48 feet on Thursday — about 20 feet above flood stage. Mayor Mike Brown declared an emergency to make equipment and other resources available, though officials said they expected no major problems. They were shoring up some areas as a precaution.

The Grand Forks area is protected by a big levee system, built after the 1997 flood forced evacuation of most of the city's residents. Officials say it is about 85 percent finished.

Weather forecasters had some unwelcome news Tuesday, as well: More rain is expected in the area later in the week, and it could extend the flooding in some areas.