By Jeff Hebert and David Muth — The recent opening of the Bonnet Carre Spillway is a dramatic reminder of our region’s precarious relationship with water and the responsibility and opportunity we have to be innovative leaders in water management.
While this year’s unusually early high river has already caused at least 29 deaths and destroyed property across Illinois, Missouri, Oklahoma and Arkansas, we’re fortunate to have the relief valves provided the Bonnet Carre and the Morganza spillways. Operated by the Army Corps of Engineers, these two structures were built following the historic 1927 flood for use during high-water events like the current situation.
Water management is a part of our reality and must be a top priority if we’re to secure our own long-term resilience. But managing the river for flood protection is not the only concern.
We cannot just keep walling the water away, because protecting ourselves from the river is not enough — we must also learn to utilize the restoration possibilities it holds. The river is the most powerful tool that we have to rebuild our suffering coast.
Before being leveed, the Mississippi River deposited its sediment load outside of the river channel, creating the very ground beneath us. The river built the natural levees on which we live and kept the wetlands lush and fertile, protecting our communities from hurricanes and tidal surges.
When we severed the river’s connection to its wetlands, we began a vicious cycle that has resulted in our current land-loss crisis. As our wetlands have disappeared, so has our region’s crucial buffer from hurricanes and sea level rise, which, sadly, leaves us even more vulnerable to even more flooding.
The most promising solution to our situation is in the river itself. Recent satellite images show the massive plumes of Mississippi River sediment being pushed to the outer-continental shelf and into Lake Pontchartrain — beyond where it can be of any immediate help to our coast. During the past two years alone, nearly 176 million tons of sediment have washed through the river — that’s the equivalent of one Ford F-150 truck per second — but much of that has been lost into the deep waters of the Gulf. This sediment is literally the foundation on which our future relies. We cannot and should not let it go to waste.
Unlike other coastal cities facing sea level rise, New Orleans has a river that is full of land-building sediment — there for the taking. We also have a powerful restoration tool at our disposal that would allow the river to mimic its natural land-building cycles. Controlled structures called sediment diversions have been studied extensively, and the state of Louisiana is prepared to move forward with two diversions downriver that have the potential to put the river’s sediment to work building new wetlands and sustain the old.
In the coming months, the Louisiana Legislature and the Coastal Protection and Restoration Authority Board will vote on whether to fund these two projects from state’s Coastal Master Plan. They are essential to our region’s long-term resiliency. This is a vote that matters to all of us. This is a chance to move forward as innovative leaders in resilience.
Water has the potential to be our region’s greatest asset or continue to be our greatest threat. The decisions we make in the coming months and years will be crucial to the long-term survival of our way of life. Managing the Mississippi River as an asset rather than an adversary is vital to our success. We can be at the forefront of climate adaptation because we are located on one of the mightiest river deltas in the world. With ingenuity and vision, we can adapt to rising seas, create a new restoration economy, safeguard critical wildlife habitat and protect our communities.
Jeff Hebert is chief resilience officer for the city of New Orleans. David Muth is director of Gulf restoration for the National Wildlife Federation, which works with the Restore the Mississippi River Delta Coalition.
You can read this online here.
