Thousands of people are being warned to prepare for the worst tonight as the Mississippi River swells to historic flood levels. Heavy rain is pushing the river's basin to its limits. That is forcing water into already swollen tributaries, and wherever else it can go.

CBS News correspondent Mark Strassmann reports that the city of Memphis is preparing for the surge, and many people in the Home of the Blues see their immediate future underwater. The city's mayor has pleaded for calm, however, and said this city possibly faced a "large-scale disaster."

Around Memphis, they're building a buffer, filling sandbags, raising levees near surging waters, and getting to higher ground. The Mississippi has become a menace.

"It's just mind-boggling to see it," said Bill and Amanda Adair, flood evacuees.

North of Memphis, Kathy Lineberry showed a photo explaining why her family's living in a camper: Their home sits in ten feet of floodwater - water that travelled four miles inland.

"What's next? We've never had anything like this. We've lost crops to the water. We've never lost a house," Lineberry said.

At the Dyer County Fairgrounds, a dozen families live in campers. They all lost a house.

"It's bad, bad for everybody. Some of us lost it all," said Keith Ables, flood victim.

Things could get much worse. After the great Mississippi flood of 1927 - the most destructive in U.S. history - engineers built an elaborate system of levees, reservoirs and floodways. By one estimate, from Cairo, Illinois, to the Gulf, it now protects four million people.

"Money that we have invested in our levees along the Mississippi River is paying off," said Col. Vernon Reichling with the U.S. Army Corps of Engineers.

That system's being tested as never before by floodwaters higher than existing records.

For the Lineberrys, their camper could be home for the next six months.

"There's nothing you can do about it. It's just stuff. All four of us are here and we're healthy and that's all that matters," Kathy Lineberry said.

A wall of sandbags is another part of Memphis trying to help itself. It has become a race against the river. The Mississippi River will crest next Wednesday at 48 feet.

It's not just the Mississippi Basin that's flooding this spring. In the northeast, heavy rains and snow melt have triggered flooding along Lake Champlain. Surging water has already swamped hundreds of homes and cottages on the lake's 600-mile coastline.

Source: cbsnews