Point-New Madrid Floodway
I do not think that my people have ever been in favor of that plan for they do not want to see southeast Missouri made the dumping ground to protect Cairo, Illinois, much as we love Cairo. That is all the Jadwin plan does. Indeed, it is doubtful it accomplishes that objective.
Dewey Short U.S. Representative from Missouri 1930
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cold weather pattern hit the Midwest, dropping signifi cant snowfall across the Upper Mississippi River Valley and south-ward along the Ohio River Valley. By mid-February a larger and deeper-than-normal snowpack covered large sections of the drainage basin above the Cairo gage, situated at the confl uence of the Mississippi and Ohio rivers. As the late winter thaw set in across the region, widespread heavy rains dropped up to 300 percent above normal amounts in most areas along the Ohio and middle Mississippi. The rivers, which were below fl ood stage, began to swell. In late February the rivers climbed even higher, as unseasonably warm temperatures rapidly melted the remaining Ohio Valley snowpack in less than 48 hours, releasing up to four additional inches of water as runoff. The melted snow and weeks of excessive rains caused widespread, but minor, fl ooding along the Ohio and middle Mississippi rivers. At the Cairo gage, the river reached 43 feet on February 28, just three feet above fl ood stage, but it had jumped 25 feet in the ten days since February 18. The wet pattern was not over, though. Heavy and repeated rains continued to pound the Ohio Valley. By mid-March, the Cairo gage exceeded 50 feet, eventu-ally climbing to more than 13 feet above fl ood stage on March 18. Then, much to the relief of fl ood-stricken areas along the middle and upper portions of the Ohio River, the active storm track shifted northward into the upper Mississippi River basin. The heavy rains and warmer tempera-tures had the same effect on the snowpack and rivers across Wisconsin, Minnesota, and Iowa. By early April a signifi cant fl ood wave developed on the upper Mississippi River, with an anticipated arrival date of late April at Cairo. The Ohio River had crested and dropped below fl ood stage at Cairo in early April, but the heavy rains returned and reversed the descent. The Cairo gage jumped back above fl ood stage on April 10.It did not permanently drop below that point again until early July.10 On April 20, the Cairo gage stood at just below 49 feet. It had risen almost a foot in 24 hours. The offi cial National Weather Service called
for a rise to 52 feet by April 30, but contingency forecasts, which rep-resent worst case scenarios, indicated a possible rise to 58 feet on the gage. How high the river would get was a matter of timing, or unusual timing in this instance. The early warm temperatures and sustained rains in the upper Midwest led to an earlier-than-normal snowmelt crest on the Mississippi River. The arrival of that crest was expected to coincide with the arrival of the second crest pulsing down the Ohio River. If both crests arrived at the same time, the confl uence area and the lower Missis-sippi River would face a deluge. If it rained on top of that, the resultant fl ooding would be worse – much worse. The National Weather Service, indeed, was keeping a close eye on an area of high pressure to the east and a trough over the Central and Western United States. That pattern created favorable conditions for a frontal system to become stationary over the Arkansas and Ohio valleys. If warm and moist air from the Gulf of Mexico streamed northward along the western periphery of the high pressure system and collided with the cooler air to the north of the front, forecasters expected heavy precipitation. With each passing moment, the likelihood of persistent rains arriving at the same time as both crests on the Mississippi and Ohio rivers became more of a reality.11
On the morning of April 21, Bill Frederick, the staff meteorolo-gist at the U.S. Army Corps of Engineers, Mississippi Valley Division (MVD) delivered his daily weather report. The National Weather Ser-vice expected the frontal system to become stationary over the Ohio, middle Mississippi, and Arkansas valleys, bringing daily rounds of intense rainfall totaling up to eight inches over the entire area through April 27. The National Weather Service still anticipated the Cairo gage to reach 52 feet on April 30, but the forecast did not include the heavi-est rains expected for the ensuing fi ve days. They would release an updated forecast, to include the anticipated fi ve-day rainfall totals, later in the afternoon during the Lower Ohio-Mississippi River Coordination Teleconference – a daily call among representatives from the National
control offi ces from the Great Lakes and Ohio River Division (LRD), MVD, and the MVD district offi ces.12
During the afternoon coordination call, the National Weather Service divulged its contingency forecast. Incorporating expected rainfall over the ensuing fi ve days, the contingency forecast showed a possible crest of 61.1 feet on the Cairo gage late on May 3 or early on May 4. Isolated models called for 62.3 feet on the gage. Anyone on the call remotely familiar with the Birds Point-New Madrid fl oodway immediately took notice of those numbers. According to the 1986 fl oodway operations plan, the forecast would necessitate the activation of the fl oodway for the fi rst time in 74 years. An action that many on that coordination call never thought would happen in their lifetimes – blowing up the Birds Point-New Madrid levee – had just become a strong possibility.