Wave Maker’s News: Setting Mississippi River Diversions Up for Success

This article is excerpted from Wave Maker’s News, our quarterly update on all things water in the Gulf of Mexico, check out the full newsletter here. Proposed Mississippi River Diversion at Myrtle Grove, images Courtesy of USGS and State of LA.Folks working on Louisiana coastal restoration have recently been getting cautiously excited about a potential silver lining from the BP oil drilling disaster: billions of dollars in Clean Water Act fines and Natural Resource Damage Assessment (NRDA) settlements flowing into the region to jumpstart restoration. If this money does come down to the Gulf for ecosystem restoration projects, that is absolutely great news, but Louisiana needs to start preparing for these restoration funds now.A key area where we could be preparing is cleaning up the Mississippi River in preparation for planned river diversions designed to build land, nourish weakened wetlands, and build new ones. One of the basic tenets of Louisiana coastal restoration has long been reintroducing the river back into the wetlands, as they have been artificially cut off by levees built to prevent flooding. Regretfully, the Mississippi River is carrying larger loads of pollutants than it did back when it was allowed to regularly flood and re-nourish coastal wetlands. This is important when considering river diversions will the pollutants in the Mississippi River, especially given the elevated levels of nitrogen and phosphorous pollution, be beneficial to the wetlands?Some scientists have speculated that if the nitrogen and phosphorus pollution levels are too high, we might get increased dead zones in diversion areas, and the wetlands created might have compromised root structures. So, in order to increase our success in these diversions, we must 1) get the EPA and Dead Zone Taskforce to set concrete, enforceable goals to achieve actual reductions of nitrogen and phosphorous pollution in the Mississippi River, 2) do comprehensive monitoring before, during, and after construction of any diversion, and 3) have an “exit strategy” in case there are unforeseen issues that could potentially do more harm than good.The bottom line is that we have not truly shown that we can build and maintain a land-building river diversion, so we have to ensure the first ones that are built are receiving the cleanest water possible and are monitored carefully. The potential money from the BP Clean Water Act fines may be our last bite at the large-scale restoration apples, so we need to make sure we set ourselves up for success.For more thoughts regarding a proposed Mississippi River Diversion at Myrtle grove, see GRN’s formal scoping comments here.Matt Rota is Science and Water Policy Director for GRN.