Quantcast

Why Midwest Floods Are Critical to the Restoration of the Louisiana Coast

Flooding isn’t generally a good thing, but historically, large floods like the ones in the Midwest this winter helped build the Mississippi River Delta and its surrounding wetlands. Rainwater from 31 states and two Canadian provinces drains into the river, carrying with it sediment—or more plainly, sand and dirt—from Midwest farm fields into the river and down to Louisiana. Over time, as the river snaked back and forth across the delta it deposited sediment like a leaking hose, creating wetlands.

Sediment filling most of Lake Pontchartrain on Jan. 26 . Photo credit: Earthdata

These wetlands provide essential habitat for wildlife and birds, as well as critical storm protection for communities by helping to block storm surge and flooding.

But by the early 20th century, the entire Mississippi River had been leveed for navigation and flood protection, straightjacketing the river and severing its tie to Louisiana’s coastal wetlands. That has meant that the sediment in the river cannot continue to support the land it built, but is instead shunted out into the Gulf of Mexico, where it settles uselessly to the bottom.

In large part because of this engineering of the river, since the 1930s Louisiana has lost nearly 1,900 square miles of land—that’s like the entire state of Delaware disappearing into the ocean. Every hour, Louisiana continues, on average, to lose a football field of land.

This land loss crisis is ongoing, leaving cities like New Orleans increasingly unprotected from storms and more vulnerable to the effects of sea level rise.

This winter’s opening of the Bonnet Carré spillway, a large flood control structure in the levee just above New Orleans, was one of the earliest on record and over the past decade, the spillway has had to be opened more frequently as weather patterns across the country shift and contribute to increased rainfall and storms in the Midwest.

Spillways like the Bonnet Carré are critical for relieving pressure on levees burdened by swollen Mississippi River waters and are miracles of engineering. But they are not designed to capture the sediment in the river for coastal restoration. We fail to take advantage of the most powerful land-building tool that we have—the Mississippi River.

Mississippi River watershed. Photo credit: NPS.gov

We need a suite of solutions that not only relieve the pressure on water levels but also build resilience to the kind of extreme weather that is making our nation’s coasts so vulnerable.

Solution: Capture the Sediment

Well-designed and strategically placed sediment diversions can help us use the sediment in the river more efficiently to help restore Louisiana’s coast.

Sediment diversions work by directing sediment and fresh water from the river into adjacent basins to build and sustain land. As the sediment compacts, it creates a base for plants to grow and thrive. These plant roots in turn help stabilize and support the new land.

In short, sediment diversions mimic the natural land-building process that once built the Mississippi River Delta thousands of years ago.

Last fall, the state of Louisiana made a commitment to move forward with two key sediment diversions in southeast Louisiana. When constructed, these diversions will help capture the sediment in the river and utilize it for coastal restoration. And during future high-water events, spillways and sediment diversions will work together to prevent flooding and rebuild coastal wetlands by directing sediment from the river to areas that need it most.

We don’t need to choose between protection and restoration. But we do need practical solutions like sediment diversions coupled with flood control measures that will allow us to enjoy the full benefits of both.

YOU MIGHT ALSO LIKE 

California Farmers Irrigate Crops With Chevron’s Oil Wastewater in Drought-Stricken Central Valley

Supreme Court Deals Blow to EPA’s Clean Power Plan, Obama Vows to Fight

165 Million Plastic Particles Are Floating in Waters Surrounding New York City

Mark Ruffalo to David Cameron: Fracking Push Is ‘Enormous Mistake’

EcoWatch Daily Newsletter

The Navajo Nation has suffered from limited freshwater resources as a result of climate, insufficient infrastructure, and contamination. They collaborated with NASA to develop the Drought Severity Evaluation Tool. NASA Goddard Space Flight Center

Native Americans are disproportionately without access to clean water, according to a new report, "Closing the Water Access Gap in the United States: A National Action Plan," to be released this afternoon, which shows that more than two million Americans do not have access to access to running water, indoor plumbing or wastewater services.

Read More Show Less
Wild Exmoor ponies graze on a meadow in the Czech Republic. rapier / iStock / Getty Images Plus

By Nanticha Ocharoenchai

In the Czech Republic, horses have become the knights in shining armor. A study published in the Journal for Nature Conservation suggests that returning feral horses to grasslands in Podyjí National Park could help boost the numbers of several threatened butterfly species.

Read More Show Less
Sponsored
(L) Selma Three Stone Engagement Ring. (R) The Greener Diamond Farm Project. MiaDonna

By Bailey Hopp

If you had to choose a diamond for your engagement ring from below or above the ground, which would you pick … and why would you pick it? This is the main question consumers are facing when picking out their diamond engagement ring today. With a dramatic increase in demand for conflict-free lab-grown diamonds, the diamond industry is shifting right before our eyes.

Read More Show Less

Despite huge strides in improving the lives of children since 1989, many of the world's poorest are being left behind, the United Nations children's fund UNICEF warned Monday.

Read More Show Less
At least seven people have died in a Bangladesh pipeline explosion. Youtube screenshot

At least seven people were killed when a gas pipeline exploded in Bangladesh Sunday, and another 25 were injured, the Associated Press reported.

Read More Show Less
Sponsored
The Shell Puget Sound Refinery in Anacortes, Washington. John Westrock / Flickr

The Washington Department of Ecology responded to an oil spill that took place Friday night when a Crowley Maritime Barge was transferring five million gallons of oil to the Shell Puget Sound Refinery, CNN reported.

Read More Show Less
Pixabay

By Claire L. Jarvis

A ruckus over biofuels has been brewing in Iowa.

Read More Show Less
Serena and Venus Williams have been known to follow a vegan diet. Edwin Martinez / Flickr / CC BY 2.0

By Whitney E. Akers

  • "The Game Changers" is a new documentary on Netflix that posits a vegan diet can improve athletic performance in professional athletes.

  • Limited studies available show that the type of diet — plant-based or omnivorous — doesn't give you an athletic advantage.

  • We talked to experts about what diet is the best for athletic performance.

Packed with record-setting athletes displaying cut physiques and explosive power, "The Game Changers," a new documentary on Netflix, has a clear message: Vegan is best.

Read More Show Less