Recently, John LaRandeau, a hydrologist with the U.S. Army Corps of Engineers in Omaha, Nebraska, acknowledged that the Missouri is likely gouging new channels and deep cuts through the valley lowlands. He remarked to a reporter with the “Omaha World-Herald,” “It’s an untamed river…I’m worried about what’s going to be there [in the valley] when it [the water level] goes back to normal.” The available evidence from the flood zone indicates that the river is not only washing away some of the richest farmland in the world, it is also destroying countless human constructs located in the bottomlands. Just this week, the Iowa Department of Transportation expressed concern that the roadways in the valley, including Interstate 29, will suffer widespread damage from the months-long flood. At Decatur, Nebraska, the Missouri continues to pound the east abutment of a bridge. Thousands of the Army’s training structures have now been underwater for six weeks. Those structures were never designed to be submerged by such high flows for so long. The likelihood that the pile dikes and revetments are being dismantled by the river is real and grows with each passing day. LaRandeau expressed his concern about the status of the Army’s navigation channel, “We hope the controls will survive the flood.”
In 1903, the Missouri provided a good example of what it is capable of doing to the valley lowlands when in flood. That year, one of the largest June rises ever recorded struck the lower valley and the two Kansas Cities. In early May, heavy rains fell upon Iowa, Nebraska, Missouri and Kansas. Then, during the period May 16 to May 31, it rained every day in portions of north-central and northeast Kansas. The saturated soils of Kansas could not absorb the additional rainfall, so the rain quickly washed off the land and into the Kaw and Missouri rivers. By May 31, the Kaw had risen far beyond its banks. At Lecompton it carried 320,000 cubic feet per second (cfs). When the flooding Kaw crashed into the already swollen Missouri, the two rivers drove one another even higher. Muddy water inundated the industrial and railroad districts of the two Kansas Cities. The West and East Bottoms neighbourhoods sank under as much as 12 feet of filthy Missouri River water. Below the surface of the river’s dark currents, the Missouri scoured cavernous holes and channels through alluvium. The river’s erosive power only became visible to the human eye after the floodwaters receded later in June. Kansas Citians saw wide-scale destruction in the manufacturing district. Factories, rail lines, and bridges had been either undermined or shattered by the Missouri’s down cutting. At the peak of the flood on June 2, the Missouri hauled 548,000 cubic feet per second (cfs) past Kansas City, Missouri. That crest equalled nearly ten times the river’s average discharge rate of 56,950 cfs past that point. Other big June rises came down the Missouri after 1903, but few have matched the size and destructive force of that flood. Although the flood of 2011 will not attain the volume of the 1903 flood – its longer duration and the greater number of constructs now in the valley – will make it a far more expensive flood. (Above photograph courtesy of Missouri Valley Special Collections, Kansas City Public Library, Kansas City, Missouri).