Those of us who live along and near the confluence of the Illinois, Mississippi and Missouri rivers are more accustomed to problems with too much water rather than too little.
This area was the heart of the Great Flood of 1993, which turned much of the Midwest into one giant lake. While 1993 wasn't the first great flood on the Mississippi (1927, 1937 and 1973 also were big ones), it remains the standard for many communities along the river. And the floods have kept coming, as in 2002 and 2008, and another huge one as recently as 2011.
That makes the situation in 2012 all the more perplexing. How can the river be near record high levels one year and now setting record lows the next?
But that's the case, and much of the blame must be laid on the widespread drought that has gripped the Midwest for more than a year. The result is that National Weather Service hydrologists expect the river at St. Louis to fall to just 9 feet deep by Dec. 30 and to 8.5 feet by Jan. 9, 2013, barring significant rainfall.
If the river falls to those low levels, barge traffic on the Mississippi likely will come to a halt. It's not the stretch of the river above St. Louis that causes the problem. The system of locks and dams on the Upper Mississippi ensures a channel deep enough for navigation. But it's the stretch between St. Louis and Cairo, Ill., that threatens to become impassable to barge traffic. That's because the Mississippi is an "open river" below St. Louis, with no dams to control the depth of the channel.
Now, a major part of the problem is the low flows on the Missouri River, which normally contributes more than half of the volume of the Mississippi below their confluence at West Alton, Mo. The U.S. Army Corps of Engineers recently began reducing the outflow from a reservoir on the upper Missouri by two-thirds in an effort to conserve water resources in the river's upper basin.
Halting barge traffic on the Mississippi below St. Louis will have a major economic impact on communities all along the Upper Mississippi and the Illinois, because shippers will be unable to send their cargoes through to the vital port of New Orleans, and likewise, nothing will be able to come upriver from below St. Louis. Thousands of navigation industry workers could be idled, and Illinois farmers and industries would be unable to get their commodities and products to market.
Unfortunately, there are no easy answers here. While commercial navigation is a huge economic interest, it must be balanced against the needs of wildlife and the environment, as well as those of the many communities that depend on these great rivers for water, recreation and tourism. States such as Montana, the Dakotas and Nebraska are clamoring to conserve their Missouri River resources, even as Missouri and Illinois see their interests hurt by the reduction of that river's flows.
This may well be the future of the Midwest for some years to come. It's possible that climate change will bring more droughts and more stress on these great rivers. The various stakeholders that depend on them need to begin planning now how best to manage these resources for the overall good of the greatest number of people and other creatures that depend on them.