HAMBURG, Iowa (Reuters) - A levee on the flood-swollen Missouri River near Hamburg, Iowa failed on Monday, sending water into low-lying farmland and prompting a flash flood watch for the town of 1,200, authorities said.
The U.S. Army Corps of Engineers said the fight against the rising waters, which is expected to drag on for weeks, would be complicated in the coming days by thunderstorms, some expected to drop as much as 5 inches of rain in places.
Monday’s breach in the levee built in the late 1940’s was initially described as 50-feet wide but is now 300 feet wide, the Corps said in an afternoon statement. The workers who were on the levee were evacuated safely.
In addition to Hamburg, areas threatened with flooding as a result of Monday’s levee break include parts of Interstate 29 and the rural residences and county roads located between the Missouri River and Hamburg, the National Weather Service said.
R.D. Hendrickson, in Hamburg from Phoenix to help his family prepare for possible flooding, witnessed the breach on Monday morning south of the town in an area of farms.
“It was surreal to see the river take the levee out,” he said. “I think it was a sand boil. The water was shooting out of the ground straight up and it just cut the levee out.... Farmers lost their entire crop out there on this one.”
Downtown Hamburg, located about 5 miles away from the breach, remained dry six hours after the levee failed but vulnerable because of its low-land topography.
Workers scrambled on Monday to build up a temporary levee at Hamburg by another three feet to provide extra insurance.
Some businesses, like the Hendrickson family’s Blue Moon Grill & Bar on Main Street, were still open for business on Monday -- though surrounded by sandbags 12 feet tall.
“Our drugstore and our little bakery on the corner are open, too,” said Wilma Hendrickson, 77, the family matriarch.
But city officials were warning those who stay behind that within 24 hours the waters would reach the secondary berm hastily built in recent days to protect the city, and that power was likely to be quickly lost when they did.
“Things are going to happen fast, I think,” said Wilma Hendrickson’s daughter, Vicki Julin, who was alerted by telephone to the rising risks by local emergency officials.
She said the family’s bar had “been a watering hole for a long time. Now it’s literally going to be a water hole.”
The Missouri River basin forms the northwest portion of the Mississippi River basin that stretches from Montana to western New York and funnels water south into the Gulf of Mexico.
Heavy winter snowmelt feeding the river’s headwaters in the Rocky Mountains, as well as heavy spring rains, have forced the Corps to release water from stressed reservoirs and dams up and down the river.
The flooding along the Missouri has already displaced thousands of people in South Dakota and threatens to add to the misery downstream in the Mississippi Valley, where record floods this spring caused billions of dollars in damage.
Last week, the Corps said the flooding on the Missouri would not cause additional on the Mississippi “without another significant rain event.”
But on Monday, the Corps said a series of storms between now and the weekend would dump between 2 and 4 inches of rain in parts of North Dakota, South Dakota, Iowa and Illinois -- and as much as 5 inches of rain in some parts of the Missouri.
Ultimately, the Corps plans water releases to peak at a rate of 150,000 cubic feet per second from the five reservoirs in the Dakotas by about mid-June, more than twice the previous record pace, and hold at least through mid-August.
The river is expected to reach up to seven feet above flood stage at Sioux City, Omaha and Kansas City when the maximum release rate is reached.
Writing by James B. Kelleher; Editing by Peter Bohan