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Posted at 01:00 PM ET, 06/22/2011

Historic flood overtopping levees in Minot, North Dakota

Missouri River also reaching record levels

From the Mississippi River to the Missouri, river flooding has been relentless in 2011. Now, the Souris River, which curls from Canada through north central North Dakota back into Canada, is reaching levels never before witnessed. The National Weather Service says the local emergency operations center has reported levees beginning to be overtopped in parts of Minot.

In response, NWS issued a flash flood warning at 9:41 central time for Minot, urging residents to “move quickly” away from evacuation zones. Eleven thousand residents have been told to leave according to reports.

On its Facebook page this morning, NWS posted the following about Minot’s levees:

Levee protection in the city of Minot averages a height of 1,558 feet, with some low spots between 1,556 and 1,558 feet. Based on no additional rainfall, no unexpected changes in upstream releases, and no unforeseen breaches or failures of levees, the current forecast suggests the 1,556 foot level will be reached sometime this afternoon and that the record level of 1,558 feet will be broken, fully overtopping the levees by Thursday morning.

On Wunderground, meteorologist/blogger Jeff Masters said this is a “1-in-100 to 1-in-200 year flood”, describing the following the factors which are leading to the historic river levels:

Massive rainfall in Canada on Sunday and Monday, combined with very heavy rainfall and snow melt over North Dakota over the past month, are responsible for the record flood. The Souris River Basin near the Rafferty Dam in Saskatchewan received four to seven inches of rain Sunday into Monday. Flood heights along the Souris River near the Canadian border upstream from Minot are already almost a foot above the previous all-time highest mark, and all that water will arrive in Minot ...

Meanwhile, in the nearby Missouri River to the southwest, the National Weather Service reports more record flooding:

....in Williston, N.D., the Missouri River is at 30.6 feet, 2.5 feet above the previous record, with only 1.5 feet remaining before the levee protecting Williston becomes overtopped. The current forecast has the river cresting and falling to 30 feet by tomorrow afternoon.


Jarrett and Jessica Hunter watch the overflowing Missouri River that flooded Corning, Missouri. June 21, 2011. Some 300 residents of a northwest Missouri town were ordered to evacuate, because of two breaches in Missouri River levees and expectations that water will top secondary barriers, officials said on Tuesday. (DAVE KAUP - REUTERS)
David Kroodsma of Climate Central wrote yesterday that the Missouri River is “currently above flood stage in every state that it passes through”. And the river may remain above flood stage through August.

In southeast Nebraska, following a flood record set in Brownville last weekend, the Associated Press reports two more Missouri River records were broken at Plattsmouth and Nebraska, topping 1993 levels.

More records may fall as the the Army Corps of Engineers (ACE) increased the amount of water released from Gavins Point Dam in South Dakota yesterday by 10,000 cubic feet per second in an effort to control reservoir levels. This increase will lead to river stages rising 0.7 to 1 foot at Sioux City, Ia., to 0.3 to 0.4 of a foot from Omaha to Rulo, Neb. At St. Joseph, Mo., the river stage rise will be roughly 0.6 foot, and at Kansas City, the rise will be roughly 0.7 foot according to ACE.

The Omaha World-Herald reports approximately 110,000 acres of land are affected by the flood waters in Nebraska. In a a release yesterday, the U.S. Army Corps of Engineers said flooded areas are expected to be inundated for several months.

The historic flooding currently underway in the north central U.S. was highlighted as a “high risk” by NOAA all the back in March when it issued its spring outlook.

Related content: Missouri River photo gallery

By  |  01:00 PM ET, 06/22/2011

Categories:  Latest, U.S. Weather

 
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