VALLEY CITY - With her city fighting a record flood, Valley City's mayor asked people to evacuate by Wednesday if they are elderly, disabled or live in low-lying areas, so crews can focus on holding off the Sheyenne River.

Valley City Mayor Mary Lee Nielson said the evacuation is voluntary, but "strongly recommended." She said it would affect about 1,450 homes, or not quite half the city of nearly 7,000 people.

Nielson asked people to leave by 6 p.m. today to free up emergency routes for equipment and crews monitoring the dikes. Repairs were needed on at least three dike leaks in a 24-hour period on Sunday and Monday.

"No one living has seen anything like what's happening in Valley City, Barnes County and the entire area. It's beyond words," said state Sen. Larry Robinson of Valley City, who was in Bismarck for the legislative session. He spent part of last weekend sandbagging, he said

The Sheyenne already has topped its 1882 record set in Valley City at 20 feet. It went to 20.62 on Tuesday morning, then dropped slightly to 20.4 feet early in the evening. The National Weather Service said the projected crest late in the week was expected in the range of 21 feet to 22 feet.

The Army Corps of Engineers slowed releases of water from the Baldhill Dam north of Valley City, but those releases are expected to pick up again, the weather service said.

"We have not yet received the big water," Nielson said.

Robinson said the flooding could last for weeks.

Rivers across North Dakota - some of them packed with ice from a wet fall, others swollen from rain and snow - have flooded since late March.

"People are tired, they're exhausted," Robinson said. "I don't think we have a good gravel road in Barnes County."

Greg Wiche, the director of the U.S. Geological Survey's Water Science Center in Bismarck, said river gauges throughout the state are showing maximum flows.

"We very seldom have basins as wet as they are now," he said. The flood risk could last a month, he said.

Robinson said community volunteers, students, National Guard members and others have worked hard to hold back the Sheyenne River in Valley City. Classes have been canceled at public schools and at Valley City State University and students have switched to sandbag duty. Robinson said a dike runs through the Valley City State campus.

"It's scary to see it under siege. It's tough," he said.

Gov. John Hoeven has doubled the number of National Guard members in Valley City to help monitor dikes. Nielson said about 450 Guard members are in the city and there were no reports of problems with the dikes overnight Monday.

"It was a blessing," she said.

Linda Sorensen was moving all her furniture to the second floor of her home Tuesday, with her phone in her mouth so she could have it handy. Sorensen and her husband, Ronald, own RJ's Plumbing and Heating business in Valley City. They and their four-member plumbing staff have been busy helping homeowners.

"Some of our guys are being hauled to homes by boat so we can keep their pumps up and running," Linda Sorensen said. Her crew and other plumbers in town also were helping people who want to evacuate, she said.

Cecily Fong, state department of emergency services, said Valley City will be able to absorb their own evacuees.

"They've identified spots in Valley City that can take their own evacuees.

"I don't think that we anticipate that we'll need any (shelters)," in Bismarck-Mandan, she said.

The Sheyenne River empties into the Red River, which is expected to reach a second flood crest of its own near Fargo this week.

Amtrak said Tuesday that it had to suspend service between Minot and St. Paul, Minn., because of track flooding east of Minot. Amtrak spokesman Marc Magliari said communities in North Dakota and Minnesota would be affected for at least 24 hours.

In Walsh County, in northeastern North Dakota, Sheriff Lauren Wild said a man missing since his pickup was swept away near the town of Park River early Sunday was presumed drowned. Two other people in the truck swam to safety.