The Midwestern Floods of 1993 and 2008

As the rivers crest throughout portions of Iowa, Wisconsin, Missouri, Illinois, and Indiana, many observers have begun comparing this year’s flooding to that of the Great Flood of 1993. There are both similarities and differences between the two natural disasters, and their respective impacts on Midwestern farmland.

The conditions that contributed to the severity of each event began well before the actual flooding occurred. Climatologists believe the stage was set for the 1993 flood with 1992’s wetter-than-normal fall, which saturated the soil. A wet winter followed with above-normal snowpack. By spring, traditionally the wettest period of the year in the Midwest, there was nowhere in the soaked ground for the rain to go. Additionally, the presence of a stronger-than-normal Bermuda High (a high pressure ridge that generally sits off the East coast) caused an almost stationary jet stream over the Midwest. Rivers overflowed in the northern portions of the region and gradually made their way south, crippling those towns in their paths. To make matters worse, even the summer months resulted in above-average precipitation. By the time the rain stopped in September, the flood had destroyed 10,000 homes, caused tens of thousands of people to be evacuated, inundated 15 million acres of farmland, and forced some river towns to permanently relocate on higher ground.

How does current flooding compare to the Great Flood of 1993? As in 1993, the Midwest experienced above-average precipitation that started in late 2007. Both floods were due to a similar weather pattern caused by the jet stream hovering over the Midwest, flooding the midsection of the country while producing a drought in the western portion of the U.S. However, the heavy rains in 1993 continued through the summer and adversely impacted every stage of crop development. The flood of 1993 also affected a vaster region of the country than the current flooding (so far), including North Dakota, South Dakota, and Nebraska (see map). Although heavy rains have hindered planting in places like Indiana and Kansas, the bulk of this year’s issues are in states along the Mississippi River.

1993 Flood-Damaged Areas

Map: U.S. Army Corps of Engineers (http://mo.water.usgs.gov/Reports/1993-Flood/)

Significant crop acreage losses resulted from 1993’s flooding. Roughly 12.7 million acres of corn and soybeans were not harvested during that crop year. Although current estimates for agricultural acreage lost to this year’s flooding are not confirmed, damage is likely to be yield-oriented and significantly less than in 1993. The USDA believes more corn was planted than was estimated in March’s Prospective Plantings report, and that this will compensate for some lost acreage. The same is to be expected for soybeans.

As a result, we will not know the full impact of 2008’s flooding until the affected crops are harvested in the fall. At that point, we can make a true comparison in terms of both crop and property damage.

When assessing the flood’s impact, one factor to remember is that yields broke records during the 1994/95 crop year, the year following the flood. Excess moisture from 1993 helped to enrich soils in impacted areas, and provided more nutrients for the planting season in 1994. Perhaps, if all other weather factors are favorable, the same will occur in 2009.

We will continue to monitor the condition of Midwestern cropland and crop production as the 2008/09 harvest progresses. For more information on how this year’s flooding may affect your commodity sourcing, please contact us.

McKEANY-FLAVELL COMPANY, INC.