A 1-in-100 to 1-in-200 year flood is in progress in North Dakota along the Souris River, where flood heights never seen in recorded history are putting unprecedented pressure on the river's levees. The Lake Darling flood control reservoir located about 15 miles upstream from Minot, North Dakota, the state's 4th largest city, is full to overflowing. Record releases of water are occurring to prevent the lake's dam from overtopping. A mandatory evacuation of 11,000 residents from Minot is underway, and must be completed before Thursday morning, when water levels on the Souris River are expected to rise several feet above the previous all-time flood height, set in 1881. 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 beginning on Thursday, likely overwhelming the city's levees and flooding large portions of the city for two or more weeks.
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