Water continued to rise along the Mississippi River and its tributaries on Wednesday, as residents in parts of Tennessee were advised to evacuate their homes and the Army Corp of Engineers considered blasting more levees to control unprecedented flooding.

The Ohio River was holding steady at 54.7 feet at Metropolis, Ill., as of Tuesday night — about the same level as when the Corps blew open Missouri’s Birds Point levee on Monday to prevent the river from rising and save a small Illinois town.

The blast dropped the river level in the town of Cairo, Ill. — situated at the confluence of the Mississippi, Missouri and Ohio rivers — about a foot and a half from where it was at the time of the breach.

But downstream from Cairo, the Mississippi continued to rise.

The lower Mississippi River is expected to crest well above flood stages in a part of the country still grappling with the devastating effects of last week’s deadly tornadoes.

As the threat grows, Army Corp of Engineers Maj. Gen. Michael Walsh — who gave the controversial order to explode the Birds Point levee and send a wall of water over 130,000 acres of rich Missouri farmland — said more Mississippi River levees might need to be breached to control rising waters.

Among those that could be tapped are the 58-year-old Morganza floodway in central Louisiana and the Bonnet Carre floodway about 30 miles north of New Orleans. Unlike the Missouri levee, these floodways can be opened using gates designed for the purpose, not explosives that unleashed the rush of floodwater into Birds Point that damaged or destroyed as many as 100 homes and washed away crop prospects for this year.

On Tuesday, a group of 25 farmers sued the U.S. government in Missouri, arguing that their land near Birds Point had been taken without adequate compensation.

U.S. Agriculture Secretary Tom Vilsack said farmers with crop insurance will be eligible for government reimbursements if their land was flooded. Other help will be available for livestock producers and tree farmers under the same programs designed for natural disasters. People who lost homes may also be eligible for rural housing loans.

Walsh said he understood the frustration over the Corps’ decision to sacrifice the levee. “But this was one of the relief valves for the system,” he added. “We were forced to use that valve.”

But farmers affected by the move remained critical.

“When you blow a hole that big, that vast and that amount of water, you’re talking two miles with a 23-, 24-foot difference in elevation from where that water is coming,” said Ed Marshall, a farmer who now has about 8,000 acres under water near Charleston, Mo.

“It’s like a small tsunami. It’s a two-mile tsunami that comes in there,” Marshall told NPR. He said some of the land that was inundated would “never recover. Ever.”

Lee Goodin is among those farmers who sued the Army Corps of Engineers for its handling of the flood control.

“Well, they have the easement to flood it. But they don’t have the easement to damage it … to destroy it,” Goodin said.

In Tennessee, flooding has already begun in Dyersburg, about 70 miles north-northeast of Memphis. Mayor John Holden said people who live in parts of the town near the North Fork of the Forked Deer River should evacuate their homes.

The Mississippi was at 43.8 feet Tuesday in Memphis, and forecasters said the city could see a near-record crest of 48 feet on May 11 — just inches away from the record of 48.7 feet set in 1937. Water from the Wolf and Loosahatchie rivers already has seeped into parts of the suburbs, and some mobile home parks were swamped.

Flood fears prompted an emergency declaration for 920,000 residents in Shelby County, where authorities blocked some suburban streets and about 220 people were staying in shelters. Emergency officials there estimate that some 5,300 homes and businesses could be affected by flooding blamed at least partly on more than 11 inches of rain that have soaked the Memphis area since April 25.

Forecasters say the Mississippi River could break records in the state of Mississippi set during catastrophic floods in 1927 and matched a decade later. Gov. Haley Barbour began warning people last week to take precautions if they live in flood-prone areas near the river, comparing the swell of water moving downstream to a pig moving through a python.

With tornados and the threat of rivers gone wild, “we’re making a lot of unfortunate history here in Mississippi in April and May,” said Jeff Rent, a Mississippi Emergency Management Agency spokesman.

Because the maximum-security Louisiana State Penitentiary at Angola is particularly flood-prone, the state plans to evacuate the most medically vulnerable inmates by next Monday, then other inmates later.

Jacob McCleland of member station KRCU in Cape Girardeau, Mo., contributed to this report, which also contains material from The Associated Press. Copyright 2011 National Public Radio. To see more, visit http://www.npr.org/.