The Flood of 1993 produced a clear headed report on how we might manage floods on the Upper Mississippi. When the opportunity came to put its recommendations into law, Congress passed. After Hurricanes Katrina and Rita ripped through Louisiana in 2005, the state produced and plan for a sustainable coast. In August 2007, a group of coastal scientists and engineers, chaired by John Lopez, issued their report, funded by the McKnight Foundation and titled, Comprehensive Recommendations Supporting the Use of the Multiple Lines of Defense Strategy to Sustain Coastal Louisiana. In 2007 Congress authoized the 2004 Louisiana Coastal Area Study with the passage of the 2007 Water Resources Development Act, but hasn’t funded it. On the morning of August 30 2005–the day after Katrina when New Orleans found itself flooded–the LCA Study looked wholly inadequate to the task of restoring Louisiana coastal marshes and protecting New Orleans from hurricanes.
Until Hurricane Betsy in 1965, the people of New Orleans worried more about flooding from the Mississippi than about flooding from hurricanes, even through the river had not flooded the city on the east bank since 1849. The Mississippi River and Tributaries Project, put in place after the Flood of 1927, was designed to short circuit floods at New Orleans and send them into Lake Pontchartrain through the Bonnet Carre structure and through the Atchafalaya Basin through the Morganza and Old River Control structures. During the Flood of 2011 the Mississippi River and Tributaries Project has been very successful at controlling flooding at Baton Rouge and New Orleans.
The sole authority of the project is flood control, not coastal restoration. The mainline levee system along the Mississippi sends floodwater and all the sediments and nutrients it carries straight out of the mouth of the river and into the Gulf of Mexico, where is it useless for land building. What goes down the Atchafalaya also goes into the Gulf of Mexico, where the Atchafalaya River is building land at its mouth. What goes into Lake Pontchartrain ends up in Mississippi Sound and Lake Borgne where it might be of some use.
A group of Louisiana coastal scientists met last week to complain that all this good mud is going to waste. Why not open the Davis Pond and Caernarvon Structures and divert all that fresh water and nutrients into Breton Sound and the Barataria Basin? The problem is oysters. The State of Louisiana has “long standing rules that prohibit the opening” of the Caernarvon and Davis Pond structures when salinity levels are low. The state opened both structures last year to push back on the oil from the BP spill. The oysters died from too much freshwater.
The questions these scientists are asking is: Why don’t we incorporate the Mississippi River and Tributaries Project into coastal restoration, so when a flood like this one comes along we can divert water and sediment to the coastal wetlands? Is it not time we stopped separating flood control and navigation from coastal restoration?