The 2012 drought, which has affected much of the cropland in the Midwest and the western United States, has also had a major effect on the level of the Mississippi River. The diminishing flow of the river has delayed barge traffic and movement of cargoes to ports at the lower mouth of the river.
40% of the conterminous United States drains into the Mississippi River. The drought, which has diminished the flow from feeder streams, has led to a 30–50 foot drop in the river level. A drop of one foot lessens the amount of cargo that can be carried downstream by 200 tons.
Landsat imagery illustrating water levels in the St. Louis, Missouri, region demonstrate the change in recent years. The 2010 image shows “normal” conditions. The river level forms a uniform line and oxbow lakes east of the river provide water for nearby crops. The 2011 image, acquired after major flooding, shows water boundaries similar to the 2010 view. However, the 2012 image shows a more narrow river with white tones representing exposed sand bars and exposed shorelines. One of the oxbow lakes is nearly dry and the larger lake has shrunk.