As Missouri asked the U.S. Supreme Court to block the corps' plan, struggling Cairo near the confluence of Ohio and Mississippi rivers resembled a ghost town. Illinois National Guard troops went door to door with law enforcers to enforce the mayor's "mandatory" evacuation order the previous night.
About 20 to 30 families were allowed to stay — a courtesy extended only to adults — in the 2,800-resident town after signing waivers acknowledging that they understood the potential peril, National Guard Sgt. 1st Class Heath Clark said.
"If you're (possibly) losing everything and don't know where to go, you wouldn't want to leave, either," he told The Associated Press during a staging area in the Cairo High School cafeteria.
Maj. Gen. Michael Walsh, the corps officer in charge of deciding whether to breach the levee, on Sunday ordered field crews to move barges to the Missouri side of the river and begin loading pipes in the levee with explosives in anticipation of blowing up a two-mile section just downriver from Cairo. He stressed that the decision to do so has not been made.
Walsh said it would take 20 hours to get the pipes filled, during which time he will review conditions before deciding what to do. Destroying the levee would provide a relief valve to ease the menacing rivers and ultimately lower them, taking pressure off Cairo's floodwall and other levees father south along the Mississippi.
But the plan possibly would inundate 130,000 acres of now-evacuated farmland in Missouri's agriculture-reliant Mississippi County, causing what Missouri argues would crush that region's economy and environment by rendering that cropland useless under potentially feet of sand and silt.
Missouri Attorney General Chris Koster, whose bid to derail the corps' plan in recent days included failed requests to a federal district judge and an appellate court, took the case to the U.S. Supreme Court, noting "it is the responsibility of this office to pursue every possible avenue of legal review."
Corps officials are monitoring water levels and haven't decided whether to go through with the blast to blunt the rise of the Ohio, which on Sunday afternoon had risen to 59.93 feet at Cairo — eclipsing the 1937 record there of 59.5 feet. The river was expected to crest Tuesday at 61.5 feet and stay there for days, raising the corps' concerns about the lingering strain water that high could put on levees. Cairo's flood wall can handle 64 feet.
Sunday's house-to-house canvass came as more thunderstorms passed through the already waterlogged, rain-pummeled region — and as emergency-management officials in Cairo focused warily on a "sand boil" — an area of river seepage that's a potential sign of trouble — pooled to 40 feet wide and 12 feet deep about 100 yards from the floodwall.
Marty Nicholson, Alexander County's emergency management coordinator, said the boil was in check, resembling a doughnut surrounded by a mound of plastic-covered rock and sandbags.
"We've had sand boils before, but never this big," Nicholson said, noting that some 70 percent of the 9,600-resident county was flooded.
ust 17 miles from Cairo, near the tiny outpost of Olive Branch, Janice Bigham watched as her husband and volunteers desperately scrambled to heighten the sandbag wall that made their ranch-style home an oasis — safe for now — from the at times swampy green floodwaters that already had swallowed up many nearby homes and outbuildings without such defenses.
"All we can do is hope and pray that they blow that levee," said Bigham, 40. "That's the only thing that might take the pressure off; otherwise, the water will be over the road and wipe out Olive Branch."
Bigham, warning sandbaggers wading into the inundation to watch out for "big-time" snakes, said the gray-and-white brick home needed to be saved, given that her late father helped build it. "That's all I have left of him," she said before turning away briefly from a reporter, her chin trembling as ears welled in her eyes.
The flooding posed the latest challenge for Cairo and the rest of Alexander County, with a non-seasonally adjusted unemployment rate naggingly around 12 percent as of March, 3 percent higher than the state's average. The cash-strapped county in recent years had several of its sheriff's cars taken back by the bank over unpaid bills.
Cairo has proud history, once serving as Gen. Ulysses S. Grant's headquarters in the Civil War's infancy before steamboats helped make it a vital transportation nexus.
By the 1920s, when 15,200 people called Cairo home, the city was a hub of commerce, thanks to rails and rivers, before its importance waned as the nation turned to interstate highways and air travel.
Matters worsened when a race riot erupted in 1967, fueling the exodus of employers and residents. The city has never recovered from it.
The riverfront now resembles an Old West stage set, its facades crumbling and windows boarded up. Some of the buildings are little more than heaps of bricks.
On Sunday, the city looked apocalyptic, its streets deserted of traffic that only included police cars. Prisoners loaded sandbags on an auto-parts business' lot, then loaded them in a fire-brigade fashion onto a dump truck under the watchful eye of guards. Churches that would have been overflowing that time of day were shuttered.
Saturated ground had given way under some streets, in one case leaving a crater about 8 feet deep near another stretch of buckled road.
Lauding the volunteerism and the orderly exodus from the city, police Chief Gary Hankins figured Cairo would weather it all.
"This city has gotten a bad rap," he said. "Like any situation of this magnitude, it's going to hopefully endear people to each other. Hopefully, this will prove our worth as far as coming together as a community."