By Kevin Murphy
KANSAS CITY, Mo (Reuters) - Flooding will force the evacuation of one-quarter of North Dakota's fourth largest city and levee breaches forced 300 residents from a Missouri town as flooding worsened, officials said on Tuesday.
About 12,000 residents of Minot have been ordered to leave their homes by 10 p.m. Wednesday as heavy water releases from reservoirs along the Souris River are expected to overwhelm the city's permanent and temporary barriers, officials said.
Heavy rains across the Souris River basin over the last six weeks have forced Canada reservoirs to release water at unprecedented rates. In turn, the Lake Darling Dam above Minot will have to release water at rates beyond current protection.
"We have been riding a pretty thin edge and regrettably, the storms over the last several days have really pushed the Souris River basin into territory that we have never seen before," said Allen Schlag, a hydrologist at the National Weather Service's office in Bismarck, North Dakota.
Schlag said the water releases from Lake Darling should be expected to cause two weeks of inundation in Minot as flows are ramped up to peak levels by late June and held there into early July before a gradual pullback.
"It's tough to imagine that when this is all shaken out and done that there will be any records that don't have 2011 stamped on them," Schlag said of the Souris River flooding.
The Minot flooding forced Amtrak to suspend Empire Builder service in part of Minnesota, North Dakota and eastern Montana on Tuesday.
Flooding along the Missouri River continued to take its toll on levees in northwest Missouri.
The 300 Craig, Missouri, residents were ordered to evacuate after two levees south and west of town on the Missouri River were breached and recently fortified earthen and sandbag barriers around the town were expected to be overwhelmed by water, Holt County Commissioner Bill Gordon said on Tuesday.
"Water is headed this way," Gordon said. "People are pretty stressed out."
In recent days breaches have inundated some farmland and homes, particularly around the village of Big Lake, Missouri.
Levees have also failed in Atchison County north of Holt County. Both counties have reported voluntary evacuations as well as the closing of numerous roads and Big Lake State Park.
TORNADOES BY THE DOZEN
Heavy rains added to woes across the Missouri River basin from Montana through Missouri Tuesday, swelling the river and its tributaries, pressuring levees and flooded areas, and forcing evacuations and road and rail closings.
The rains were coupled with record water releases from six U.S. Army Corps of Engineers operated dams from Montana through South Dakota to relieve pressure on reservoirs swollen by snow melt and heavy rains.
Peak releases are planned until at least mid-August and high flows are expected until December.
Heavy rain stretched across Nebraska through South Dakota and into Minnesota Monday into Tuesday.
More than three dozen reports of tornadoes were logged in northwest Kansas and southern Nebraska from Monday afternoon to evening with no serious injuries, though damaging homes, cars and power lines, the weather service said.
In Nebraska, thunderstorms brought hail more than an inch in diameter and wind gusts reported up to 70 miles per hour, knocking down trees and power lines, damaging farmsteads and tearing the roof off a house, the weather service said.
Flooding and heavier water flows have forced the closure of bridge crossings of the Missouri River from just south of Omaha for more than 100 miles south. More bridges and railroad lines may have to close as flooding continues.
North of Omaha, the Fort Calhoun nuclear power station remains shut due to Missouri River flooding, but protected by temporary flood barriers and dry, said Mike Jones a spokesman for the Omaha Public Power District.
Two coal-burning power plants along the river are operating and also protected by flood barriers, Jones said.
The Cooper nuclear power station near Brownville, Nebraska, is operating and protected by flood barriers, said Mark Becker, a Nebraska Public Power District spokesman.
In North Dakota and South Dakota the rains strained pumps that clear water from streets when flood barriers prevent runoff into the river.
(Additional reporting by David Bailey in Minneapolis; Editing by Greg McCune)