Scientists Endorse Mississippi Diversion Project to Restore Louisiana Wetlands

Motivated by the destructive lessons of Hurricane Katrina and the specter of sea level rise related to climate change, many scientists are now recommending a new project to divert the flow of the Mississippi River in a bid to restore Louisiana’s disappearing wetlands. One quarter of Louisiana’s wetlands has been lost since the 1930s. After many decades of destructive human intervention, the diversion would allow river sediment to replenish wetlands, stop the land from subsiding, and rebuild barrier islands critical for protection against hurricanes and storm surges. An April 2006 meeting of dozens of scientists and engineers gathering to discuss the future of the Louisiana coast strongly endorsed an idea that had previously been regarded as unaffordable or detrimental to the regional economy. Louisiana is convening a planning meeting to pursue the diversion idea in the fall of 2006. The Mississippi carries some 120 million tons of sediment annually into the Gulf of Mexico—enough to cover 60 square miles (or 155 square kilometers) with half an inch of sediment. But because of dams, levees, and other human interventions, the sediment ends up in deep water instead of replenishing coastal marshes and shallow waters. Although a diversion project could easily take a decade or more to design and build and would be very expensive to carry out, the cost of not acting is likely to be higher.