Defences crumble as mighty rivers merge: Homes abandoned to the flood amid torrential rains as waters of the Mississippi and Missouri defeat efforts to contain them

ON THE eve of another visit by President Bill Clinton to the disaster area, rampant Nature in the flooded Midwest was poised to stage its mightiest demonstration of raw power yet, as the bloated Mississippi and Missouri rivers began to merge some 20 miles north of their usual point of confluence.

Early yesterday levees guarding the channels of both rivers - each between 10ft and 15ft above their flood levels - were starting to crumble. As the two join forces, much of St Charles County, a peninsula only 15 miles north of downtown St Louis, is being turned into an island. More than 7,000 people have already been evacuated. Yesterday the last defiant residents were leaving, temporarily at least abandoning their homes and possessions to the raging brown floodwaters.

Thanks to a fresh bout of storms and torrential rains the long-feared crisis has overtaken St Charles more quickly than expected. On Thursday new deluges cascaded down on parts of Missouri and Iowa. Today between 1in and 4in of rain are expected over much of the region, and the outlook is for more of the same, at least until tomorrow.

Elsewhere across the Midwestern floodplains, the picture is mixed. In Des Moines, Iowa, a city with a population of 250,000 and which had become the largest ever in the US to lose its water supply (as a result of a contaminated treatment plant), the Des Moines and Raccoon rivers are starting to recede. But a desperate struggle continues to keep open the bridge at Quincy, Illinois, the only one still open on a 260-mile stretch of the Mississippi above St Louis.

And as some residents embark on the dispiriting task of clearing up after the mess, others further afield are getting a first taste of it. A record 7in of rain along the border of North Dakota and Minnesota sent the Red River bursting its banks to flood parts of the city of Fargo on Thursday.

Despite the Herculean efforts of National Guardsmen, local residents and volunteers who have flocked to the threatened communities, the disruption to ordinary life in America's heartland grows steadily worse. Barge traffic on the country's most important commercial riverway is completely paralysed.

Eleven Midwestern airports were reported closed yesterday. More than 8 million acres have been flooded, and the estimated damage is growing by the day.

The President, who is due in St Louis today to meet the governors of nine stricken states and top relief officials, now concedes that the dollars 2.5bn ( pounds 1.7bn) assistance package he announced only three days ago is completely inadequate. But, he warned on Thursday, 'people cannot expect the government to pay for all their losses'. FEMA, the federal disaster agency, is now talking of a final flooding bill of up to dollars 8bn, far above the current estimate of dollars 5bn.

The Mississippi was due to crest yesterday in Mark Twain's home town of Hannibal, Missouri, where local officials are praying the historic old district of the town can be protected. But such has been the extra rain that Sunday's expected crest at St Louis itself, of a record 45ft 6in, has been put back 24 hours. However, 52- foot-high levees should save the centre of the city and its immediate suburbs from the worst.

(Photograph omitted)