Let The River Run Through It: Harnessing the Mississippi to Save Louisiana's Wetlands from the Oil Spill

As shown in this satellite photo of the Wax Lake Delta, the Mississippi River and its distributaries discharge massive amounts of water and sediment into the Gulf. Could they also clear wetlands covered in oil? Some scientists say yes (Source: EurekAlert.org)

In case you lost track, we're now just days away from the three-month anniversary of the Deepwater Horizon disaster. As we near the 90-day mark, engineers are still scrambling to cap the well that has pumped millions of barrels of oil into the waters off southern Louisiana. With crude continuing to float into coastal marshes, area residents have been left wondering how oil will be prevented from destroying the wetlands that they call home.

Engineers, energy companies, and the government have proposed a veritable suite of mitigation techniques, from booms to berms to rock dikes, but none has yet emerged as an effective, sustainable, and economically sound solution. Indeed, unfinished artificial islands constructed to shield the coast from the oil spill have already begun crumbling into the Gulf of Mexico.

As a complement to the previously-mentioned proposals, why not use the natural flow of the mighty Mississippi to protect the coastal region? After all, the river’s been flowing into the Gulf and sustaining the delta for thousands of years. Like a massive water hose, the Mississippi could potentially flush oil out of the wetlands and accelerate sediment deposition in degraded parts of delta, making the area more resilient to future disasters.

Several prominent coastal scientists have advocated harnessing the Mississippi River for this purpose. In a memo sent earlier this summer to the EPA Tech Team, Dr. Paul Kemp, a scientist at the National Audubon Society, outlined this method of preventing oil encroachment in Louisiana’s coastal region. Kemp suggested that, at least temporarily, active management of existing US Army Corp of Engineers structures at Old River could allow the flow of the Mississippi to force oil away from the Pelican State’s wetlands.

In its current state, the Mississippi is a complex man-made water management system that prevents flooding in cities like New Orleans that line its banks. However, experts like Kemp believe that a shift in tributary streams would allow a more "robust" flow. This would keep the oil at bay and buy time for cleanup crews struggling to contain the mess. At the same time, flooding could still be prevented in low-lying communities if levees and pumping stations are managed correctly by river engineers.

Diversion of the Mississippi would have other benefits as well. Land loss is a problem that's been plaguing Louisiana since long before the Deepwater Horizon Spill. Since 1930, over 2,000 square miles of land have been lost, equivalent to 70% of the original ecosystem. Redirecting the natural flow of the Mississippi could not only prevent further disaster in the wake of the BP spill, but could also segue nicely into coastal restoration, as the river deposits much needed sediment back into the Mississippi River Delta. As an added lagniappe, accelerated construction of river diversions could create thousands of near-term jobs for contractors, engineers, and others seeking work.

There are, of course, uncertainties that come coupled with an ambitious river diversion project. For example, freshwater from the diversions could alter the salinity in nearly estuaries and bays, affecting sensitive organisms like oysters that are vital to Louisiana’s fishing interests. It’s also difficult to predict just how effective diversions would be for coastal restoration, but models in place have already been successful in restoring parts of the Atchafalaya and building the Wax Lake Delta.

Still, when weighed against the alternatives, using the river in oil spill response seems like a idea worth pursuing. John Day, a professor emeritus at LSU and an eminent coastal scientist in his own right, captured the potential promise of the river to power remediation of the Gulf Coast, noting

“As the great Mississippi River Delta disappears, so do the ecosystems, economies and people that it holds. The Mississippi River is the solution. It has the water, sediment and energy to rebuild land, defend against hurricanes and again provide habitat, safety, livelihood, and prosperity. We must look to the natural functioning of the delta to guide us in restoration.”

Let's hope someone's listening.