Disaster foretold

ROBERT CRISS does not relish his role as Cassandra of the Mississippi. For years the geologist at Washington University in St Louis has warned policymakers about building houses and businesses on flood plains, walling off rivers with dams, locks, dykes and levees, disregarding the consequences of global warming on weather patterns and the use of outdated statistics for calculating the risk of a major flood. “The devil could not have come up with a better plot,” he says.

Torrential rain started on December 26th and lasted three days, during which 9-14 inches (23-35cm) of rain deluged much of Missouri and parts of Illinois, according to the National Weather Service. Thousands had to evacuate their houses; businesses abandoned shops and stock. Amtrak stopped its local train service for four days and long stretches of the I-44 and I-55 interstate highways, as well as 200 state highways, were shut off. Twenty-five people died, mostly because they drove onto a swamped road and their cars flipped over. It will take months to rebuild what has been lost. Yet the bigger question is whether enough was done before the rains came to mitigate the impact of flooding.

For Mr Criss the answer is no. He does not understand why the development of commercial and residential property was allowed on flood plains near St Louis, in particular as both the city and the county are losing population. The area should have been kept as farmland, which can absorb water, he argues, and should not be paved over: when the floods come, lost crops are far less costly than lost houses and businesses.

Nicholas Pinter at the University of California, Davis adds that the Missouri and the Mississippi are flooding so severely because the middle stretch of the Mississippi (which joins the Missouri at St Louis) has more navigational dykes than any other river reach he knows. It has become a largely man-made construct that bears little resemblance to the river of 200 years ago, which changed shape with the volume of water flowing through it. Yet the statistics used by the Army Corps of Engineers and the Federal Emergency Management Agency (FEMA) to define flood risk are based on the average weather patterns, flooding and the changing shape of the river during the past 100 years. Unless the corps and FEMA update their statistical methods, they will continue to underestimate the flood risk for the region.

Missouri policymakers have largely ignored the geologists’ warnings about floods. After the Great Flood in 1993, which destroyed around 100,000 homes and caused nearly $20 billion in damage along the Missouri and upper Mississippi, the Galloway Report, written by a group of experts appointed by the White House, called for federal flood-insurance programmes to discourage development in flood plains. It said that taxpayers should stop bailing out areas that flood regularly. And it recommended that the basins of the Missouri and Mississippi should be managed as one watershed. Very little of this has happened. “This misery will repeat itself,” predicts Mr Criss.