Rising water in northeast North Dakota has Pembina County officials worried that the Renwick Dam could give way, prompting the mandatory evacuation of more than a thousand residents.
The Fargo Forum reports the area received 6 to 7 inches of rain over four days leading up to Tuesday, raising the Tongue River levels and filling up reservoirs.
The water was rising at about 4 inches per hour Tuesday, but had slowed to a tenth of an inch per hour Wednesday morning, according to the Grand Forks Herald.
If the dam fails, the city of Cavalier would see major flooding. Construction crews spent much of Tuesday building emergency levees.
WDAZ has video.
An emergency shelter run by the American Red Cross volunteer was opened at a public school in Drayton, N.D.
The National Guard and sheriff's deputies are blocking any traffic from entering Cavalier.
About 30 miles south, the Associated Press reports emergency levees were also being built in Grafton, a city of about 4,500, as the Park River nears a record crest.