With the click of a mouse, you can track the swollen Mississippi River in real time as it plods downstream, overwhelming levees and elbowing beyond its banks.
But you can’t find a complete list of levees built along the upper half of the river and its tributaries. Not on the Internet. Not even from the U.S. Army Corps of Engineers, charged with managing flood control on the Mississippi.
You can’t find it because it doesn’t exist. That seems incomprehensible in an age of satellite mapping and billion-dollar damage estimates. But it’s a fact.
There is such a list for the lower Mississippi; after serious flooding in 1927, the entire region was put under the corps’ direct control. Levees on the lower Mississippi must be built to a single standard and certified by the corps.
That’s not true north of St. Louis. Protections there are a patchwork quilt of local, municipal and even private levees. Some are the equal of anything to the south; others are overgrown, sandy or weakened by burrowing animals. Authorities were blaming muskrat dens for having helped undermine the Pin Oak levee near Winfield on Friday morning.
The corps, alone and in partnership with local entities, operates about 2,000 levees on the upper Mississippi River. Thousands of others — no one knows how many — are privately owned.
One of the lessons supposedly learned after the disastrous 1993 floods, when more than 1,100 levees failed, was the need for a complete inventory. That was among the key recommendations made by a committee of experts in a 272-page report commissioned after the Great Flood of 1993. It also recommended that everyone living in a flood plain be required to buy flood insurance.
Knowing where all the levees are located and who owns them would permit the corps to assess their state of repair and predict which could be overwhelmed during conditions of high water.
Last year, Congress passed the National Levee Safety Act, which requires the corps to inventory all private levees. Congress has yet to give the corps any money to pay for it, however. No money, no inventory.
In recent weeks, the nation’s attention has been riveted to conditions along the upper Mississippi, where flooding has claimed two dozen lives and caused billions in property damage.
If history is any guide, when the waters recede, so, too, will the resolve to make necessary, systematic changes. But the heavy rains that caused the Mississippi River to overspill its banks this year are not unprecedented. Similar rains — and similar floods — are sure to occur in the not-so-distant future.
Without a systematic approach to flood control and prevention, we’ll continue on the same haphazard course: increasing development in flood plains, building ever higher berms and, when the waters rise again, sandbagging levees and taxpayers alike.

Robert Cohen/Post-Dispatch photo