WYATT, Mo. - The dramatic, late-night demolition of a huge earthen levee sent chocolate-colored floodwaters pouring onto thousands of acres of Missouri farmland Tuesday, easing the threat to a tiny Illinois town being menaced by the Mississippi River.

But the blast near Cairo, Ill., did nothing to ease the risk of more trouble downstream, where the mighty river is expected to rise to its highest levels since the 1920s in some parts of Tennessee, Mississippi and Louisiana.

"We're making a lot of unfortunate history here in Mississippi in April and May," said Jeff Rent, a spokesman for the Mississippi Emergency Management Agency. "We had the historic tornados, and now this could be a historic event."

The Army Corps of Engineers was considering making similar use of other "floodways" - enormous basins surrounded by giant levees that can be opened to divert floodwaters.

A staccato series of explosions lit up the night sky Monday over the Mississippi with orange flashes and opened a massive hole in the Birds Point levee. A wall of water up to 15 feet high swiftly filled corn, soybean and wheat fields in southeast Missouri.

Upstream at Cairo, which sits precariously at the confluence of the swollen Mississippi and Ohio rivers, preliminary readings suggested the explosion worked.

But across the river, clearing skies gave a heartbreaking view of the inundation triggered by the demolition. The torrent swamped an estimated 200 square miles, washing away crop prospects for this year and damaging or destroying as many as 100 homes.

A group of 25 farmers sued the federal government Tuesday, arguing that their land had been taken without adequate compensation.

At a spot along the Birds Point levee, 56-year-old Ray Presson looked through binoculars to see just how high the water stood at his 101-year-old home and the 2,400 acres he farms around it. Presson is staying with a cousin in nearby Charleston, and he's not sure when, or if, he'll get to go home.

"It could be three weeks. It could be two months," he said. "The government's not giving us any kind of timetable."

Agriculture Secretary Tom Vilsack said farmers who had crop insurance will be eligible for government reimbursements if their land was flooded.

Other forms of 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.

Missouri Gov. Jay Nixon, who stood behind the state's failed legal fight to stop the destruction of the levee, said state leaders would do everything "within our power to make sure the levee is rebuilt and those fields, the most fertile fields in the heartland, are put back in production."

By blowing the levee, the corps hoped to reduce the river level at Cairo and ease pressure on the floodwall protecting the town. As of Tuesday afternoon, the Mississippi had receded to 60.2 feet and continued to fall, a day after a record crest.

"Things look slightly better, but we're not out of the woods," Police Chief Gary Hankins said while driving his patrol car past jail inmates assigned to fill sandbags outside an auto-parts store.

But if Cairo and other spots were dodging disaster, ominous flooding forecasts were raising alarm from southeast Missouri to Louisiana and Mississippi.

In Missouri, the town of Caruthersville was bracing for a crest of 49.7 feet later this week. The flood wall protecting the town can hold back up to 50 feet, but a sustained crest will pressure the wall. Workers have been fortifying the concrete and earthen barrier with thousands of sand bags.

Memphis could see a near-record crest of 48 feet on May 10, just inches lower than the record of 48.7 feet in 1937. Water from the Wolf and Loosahatchie rivers has already seeped into parts of the suburbs, and some mobile home parks were inundated.

Flooding fears prompted Shelby County authorities to declare an emergency for 920,000 residents. Authorities blocked some suburban streets, and about 220 people were staying in shelters.

Farther south, the lower Mississippi River was expected to crest well above flood stages in a region still dealing with the aftermath of last week's deadly tornadoes.

Forecasters say the river could break records in Mississippi that were set during catastrophic floods in 1927 and 1937. Gov. Haley Barbour started warning people last week to take precautions if they live in flood-prone areas near the river. He compared the swell of water moving downriver to a pig moving through a python.

Maj. Gen. Michael Walsh - the man ultimately responsible for the decision to go through with breaking the Missouri levee - has indicated that he may not stop. In recent days, Walsh has said he might also make use of other downstream basins surrounded by levees that can intentionally be opened to divert floodwaters.

Unlike the Missouri levee, these floodways can be opened using gates designed for the purpose, not explosives.

Among the structures that could be tapped are the 58-year-old Morganza floodway near Morgan City, La., and the Bonnet Carre floodway about 30 miles north of New Orleans. The Morganza has been pressed into service just once, in 1973. The Bonnet Carre, which was christened in 1932 has been opened nine times since 1937, most recently in 2008.

During a news conference Tuesday night, Walsh characterized the chances of being forced to open the Bonnet Carre flood gates as "high" and the chances at Morganza as "medium." He expects to decide on the Bonnet Carre as early as Thursday, and on Morganza next week.

He said there are no homes in the Bonnet Carre floodway, though there are scattered homes and farmland in the Morganza floodway.

After Memphis, the Mississippi River is expected to crest May 12 at Helena, Ark., and further south in the following days. Forecasters predict record levels at the towns of Vicksburg and Natchez, Miss.

High water has already shut down nine river casinos in northwest Mississippi's Tunica County, where about 600 residents have been evacuated from flood-prone areas on the inside of the levee, said county spokesman Larry Liddell.

"We're concerned, but as long as the levee holds we'll be all right. And we don't have any doubt that the levee is going to hold," Liddell said. "We have the strongest levees in the country."

Retired Major Gen. Tom Sands, a former president of the Mississippi River Commission and former Army Corps engineer, said the corps was pursuing a plan to manage the high water with spillways and other release valves, such as hundreds of relief wells that take water out of the river.

The Misssissippi River is carrying about 2.3 million cubic feet of water per second, and the levee system along it was designed to handle 3 million cubic feet of water per second at the Old River Control Structure, a massive floodgate north of Baton Rouge to keep the Mississippi River from diverting course and flowing into the Atchafalaya River.

Back in Missouri, Mark and Rebecca Dugan took pictures atop the Birds Point levee of their farmland - 3,000 acres. This year's wheat was a bumper crop and ready for harvest. Mark figures it was worth $350,000 to $400,000. All told, he estimates he will lose $1.8 million in gross revenue from the breach.

The couple said the government owes it to landowners below the levee to make full reparations, but both were skeptical it would happen.

"What do they say are the nine scariest words in the English language?" Rebecca Dugan said, "'I'm from the government and I'm here to help.' "

Walsh acknowledged it could be late summer or early fall before the water fully drains off the land. Sediment and moisture could do lasting damage.

"This is where generations and generations live," Walsh said. "I understand that, but this was one of the relief valves for the system. We were forced to use that valve."

Associated Press writers Cain Burdeau in New Orleans and Holbrook Mohr in Jackson, Miss., contributed to this report.