Major flooding is nothing new to the St. Louis area. More about the 1993 ‘Great Flood’

The St. Louis and southwest Illinois regions experienced heavy rainfall late Monday into Tuesday, and areas in Belleville, Swansea, St. Louis and East St. Louis are seeing spots of extreme flooding.

The National Weather Service St. Louis reported the crest of the Mississippi River at St. Louis was at 9.25 feet at 3 p.m. Tuesday, and Tuesday afternoon’s forecast said it would peak at 12.3 feet around 7 p.m. Wednesday.

To provide some historic context for the Mississippi River’s peak and flooding in the region, we’ve gathered some information about major events in St. Louis’ past.

The “Great Flood” of St. Louis in 1993 is considered “the most costly and devastating flood to ravage the U.S. in modern history,” according to the NWS.

The flood occurred from May to September of that year and peaked Aug. 1, when the Mississippi River reached 49.58 feet in St. Louis, the highest point ever recorded.

Major flooding occurred in Missouri, Illinois, Iowa, Wisconsin, Minnesota, Kansas, North Dakota, South Dakota and Nebraska, according to the U.S. Geological Survey.

Heavy rain throughout summer 1993 led to the mass flooding. A single day could see 5 to 7 inches of rainfall, and river gages malfunctioned due to the record-breaking crests of the Mississippi and Missouri rivers, according to USGS.

Snowmelt saturated soil earlier in the year, leading the excessive rainfall to have a greater effect than what’s typical, according to Washington University in St. Louis.

Levee breaks in the 1993 event were frequently reported as early as June 7, the NWS says, While the temporary storage of excess water in lowlands delayed flood crests, rain outpaced the effect.

“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 places like St. Louis Missouri, river levels were nearly 20 feet above flood stage and had never been this high in its 150 year history,” the NWS website reads.

More than 45 people died as a direct result of the flooding, the USGS reports, and approximately 50,000 homes were either damaged or destroyed.

The disaster also resulted in an estimated $15 billion to $20 billion in losses.

In addition to the lives lost and homes destroyed, the flooding caused water quality degradation and pollution.

The next-highest crest of the Mississippi River in St. Louis to 1993’s mass flooding was 46.02 feet in 2019, followed by 43.23 in 1973, 42.52 in 2016 and 42 in 1785, according to the NWS.

The flooding in 1973 caused a series of levee failures, KSDK reported, and the Mississippi River was in flood stages that year from March 10 to May 26.