Monday, May 23, 2011

Learning from the Floods

As the Mississippi River’s waters rise to levels unseen since the 1930s, and floodgates are opened to relieve pressure from the swollen river, scientists hope to turn these dire circumstances into an opportunity to study how the river behaves.

Researchers at Louisiana State University are looking at where the river will deposit sediment, the silt and sand in the water, and how the land around the river can be built up. In fact Louisiana has been losing about a football field of land per hour due to the fact that the Mississippi River has been engineered to prevent floods, and consequently it no longer drops sediment on the land, which is how the Mississippi River delta, including Louisiana and its cities, was formed. The absence of sediment also means the valuable wetlands are being lost, causing the loss of protection against hurricanes and storm surges from the sea.

Although devastating for many residents along the river, the terrible floods will allow scientists to determine how to stop the problem of land erosion. Observing how the silt is deposited and where it goes will reveal how to direct the silt to certain areas of land that can be built up. Then the flood waters could be directed to the areas that need the silt.

Go to the BBC’s Science in Action programme of May 19 to hear more on this study.