Jefferson County - East-West Gateway Coordinating Council

A Regional Overview All-Hazard Mitigation Plan 17
Over 1,000 flood warnings and statements, five times the normal, were issued to notify the
public and need-to-know officials of river levels. In St. Louis, river levels were nearly 20 feet
above flood stage, the highest in the city’s 150-year history. The 52-foot St. Louis Flood
wall, built to handle the volume of the 1844 flood, was able to keep the 1993 flood out
with just over two feet to spare. On the Missouri River it was estimated that nearly all of
the 700 privately built agricultural levees were overtopped or destroyed. Navigation on the
Mississippi and Missouri River had been closed since early July resulting in a loss of $2
million (1993) dollars per day in commerce.
The Mississippi River at St. Louis crested at 49.6 feet on August 1, nearly 20 feet above
flood stage and had a peak flow rate of 1.08 million cubic feet per second. The old record
was 43.2 feet in 1973. Some locations on the Mississippi River were in flood for almost
200 days while locations on the Missouri neared 100 days of flooding. On the Mississippi
River, Grafton, Illinois recorded flooding for 195 days, Clarksville, Missouri for 187 days,
Winfield, Missouri for 183 days, Hannibal, Missouri for 174 days, and Quincy, Illinois for
152 days. The Missouri River was above flood stage for 62 days in Jefferson City, Missouri,
77 days at Hermann, Missouri and for 94 days at St. Charles in the St. Louis metropolitan
area. On October 7, 103 days after it began, the Mississippi River at St. Louis finally
dropped below flood stage.
According to the U.S. Army Corps of Engineers (as noted in the NOAA National Weather
Service disaster survey report) 40 of 229 federal levees and 1,043 of 1,347 non-federal
levees were over-topped or damaged. Every breeched levee contributed to the amount of
floodwater flowing outside the main drainages. The flood eroded more than 600 billion
tons of topsoil and deposited great amounts of sand and silt on valuable farmland. In large
areas inundated by the flood, the harvest of 1993 was a total loss and some farmers lost
any chance for a 1994 harvest.
At St. Louis, the first spring flooding on the Mississippi River was recorded April 8, cresting
at 0.2 feet above flood stage and lasting only that day. The Mississippi rose above flood
stage again on April 11 and stayed above flood stage until May 24. The city got a respite
as the Mississippi stayed below flood stage May 24 to June 26. On June 27, the Mississippi
again went above flood stage and did not drop below flood stage until October 7—a total
of 146 days above flood stage. The Mississippi River was above the old record flood stage
for more than three weeks at St. Louis from mid July to mid August. Prior to 1993, the
historic flood of record on the Mississippi River at St. Louis had been 43.2 feet, recorded
April 28, 1973. That record was broken July 21, 1993, with a level of 46.9 feet and broken
again 11 days later with a record stage of 49.58 feet on Aug. 1. St. Louis is located near
the confluence of the Missouri, Illinois and Mississippi rivers, all of which were in flood at
the same time.
From April through October, 1993, flooding of the Upper Mississippi River and the
Missouri River caused a national catastrophe, interrupting transcontinental commerce for
many weeks, including rail, highway and barge traffic. Tremendous outlays of local, state
and federal dollars to aid recovery of people and property created major financial