Louisiana is awash in talented scientists, who have spent their working lives thinking about the Louisiana Coastal wetlands and how to restore them. In researching and writing The Mississippi: A Visual Biography, I encountered more work by scientists in Louisiana than any other of the states that border on the river. Minnesota comes as a close second. Maybe it is the urgency of stopping the decline of the remaining wetlands and creating more.
The Mississippi’s flow is divided at the Old River Control Structure, with 30% going down the Atchafalaya and 70% down the Mississippi. In 2006 G. Paul Kemp and his partner Emily Hyfield (page 9 0f the pdf file) noted that only 10% of the sediment going down the Atchafalaya was actually building new land at the mouth of the Atchafayala and at the mouth of the Wax Lake outlet. The rest was lost to the Gulf of Mexico.
They proposed that more water be diverted down the Atchafalaya, up to 70 %, and much of that be diverted to a spillway that would run through Lake Palourde and south into the Penchant Basin, a large area of fresh marshes, including flotants, floating marshes.
Presently, the Penchant Basin gets its inputs of freshwater from the Atchafalaya in a roundabout way: it flows around Avoca Island to Bayou Penchant and into the marshes. Their proposal is one small part of the Multiple Lines of Defense Project, which divides the Louisiana Coast along the lines of the 1998 $14 billion Coast 2050 proposal, which Congress never authorized and therefore was never funded and then was replaced by the less ambitious and less costly, $2 billion, 2004 LCA Study, which Congress authorized in the 2007 Water Resources Development Act, but has yet to fund.
Today, at cnn.com, Kemp is proposing closing some of the gates in the Old River Control Structure and increasing the amount of water going down the Mississippi to flush oil out of the wetlands. At the beginning of this disaster, Louisiana opened the gates in its diversion structures at Caernarvon and Davis Pond and diverted Mississippi water into Breton Soung and the Barataria Basin respectively and held back the encroachment of oil into the wetlands, for a time. The river itself kept the oil at bay in the gulf, as long as it was flooded, for a time. Spring flooding has eased and the river is no longer pushing back the oil. Kemp wants to see the amount of water going down the Mississippi increased to 80%. The Atchafalaya won’t suffer really, because it also carries the flow of the Red River. In fact, the river swamp may benefit from have a little less water for a while. Mud flats would be exposed and cypress might germinate.
If you take his CNN editorial and in his and Hyfield’s spillway proposal, you see that Kemp is proposing that we use the Old River Control Structure as a flexible tool for land building, for marsh nourishment, for pushing back salt water encroachment, and for pushing back the oil from the great BP gusher.