US South braces for record floods

US engineers are preparing to flood up to three million acres in southern Louisiana in a bid to protect large cities along the Mississippi River.

The Army Corps of Engineers said it would open floodgates to divert water from the river this weekend. As many as 25,000 people are preparing to leave.

Opening the Morganza Spillway would ease pressure on levees protecting the cities of Baton Rouge and New Orleans.

The Mississippi River has risen this year to levels not seen in decades.

Fed by rainwater and the spring thaw, the river and its tributaries have caused massive flooding upstream, and officials have said the flooding in Louisiana is the worst since 1927.

Louisiana state officials said late on Friday that the Army Corps of Engineers would open the Morganza Spillway within the next 24 hours.

Louisiana Governor Bobby Jindal said the release of water would be slow.

The trigger for the spillway opening was when 1.5m cubic feet (42,500 cubic metres) of water per second was flowing down the Mississippi River at Red River Landing, just north of the Morganza Spillway.

That flow rate had already been reached, the National Weather Service said, according to Associated Press news agency.

‘Pack everything’

Opening the spillway will channel water out of the flooded Mississippi River and into the Atchafalaya River basin, a low-lying area of central Louisiana, to avoid flooding Baton Rouge, New Orleans and other cities.

The Corps warned that if the spillway was not opened, New Orleans could be flooded by about 20 feet (six metres) of water.

Instead, water will flow south into the Atchafalaya Basin, flooding homes and farms in the state’s Cajun country under an expected 10-20 feet of water.

Over several days, the water should run south to Morgan City and then into the Gulf of Mexico.

Workers are rushing to reinforce the levees around Morgan City.

Much of the water would end up in swamplands, bayous and backwater lakes but several thousand homes are at risk of flooding.

“My message to our people is they don’t need to be delaying,” Gov Jindal said on Thursday. “Move their valuables. Think about where they would go.”

Residents of the town of Butte La Rose, directly in the path of the spillway’s water, said they had been told to pack for a long absence.

“They told us to move as though we were moving – period – not coming back, not to so much as leave a toothpick behind,” said one woman.

“Nobody knows what’s going to happen to that spillway,” a man told AP. “It could be totally demolished, where this will be the Mississippi one day.”

Farmers in the region are expecting to lose their entire crops in a year of high prices for farm produce.

Record flooding

The Morganza Spillway, 45 miles (72km) north-west of Baton Rouge, was last opened in 1973.

The flooding is approaching records set 84 years ago when hundreds of people in the region died.

At the Arkansas town of Helena, the river has crested at 56.5 feet.

The flood surge is expected to reach Vicksburg, Mississippi, on 19 May, reaching 57.5 feet – above the record 56.2 feet of 1927. The river begins overflowing its banks at Vicksburg at 43 feet.

Earlier this week, the Mississippi River flooded parts of Memphis, Tennessee, the city famed as one of the birthplaces of rock and roll and blues music.

Further upstream, the Army Corps of Engineers has opened floodways in Missouri to keep pressure off levees protecting the town of Cairo, Illinois.

The US government has said farmers whose land has been flooded will be reimbursed for destroyed crops.