Army Corps Build 1,500-Foot-Wide Levee in Mississippi River to Keep Salt Water Out of Drinking Water

by Megan Molseed
(Getty Images/SOPA Images / Contributor)

The Mississippi River continues to see plunging water levels as drought continues to plague areas all over the country. As a result, the US Army Corps of Engineers is launching the construction of a massive underwater levee in an effort to prevent saltwater from flowing upriver as the crisis continues.

Mississippi Water Levels Are Falling While Sea Levels Are Rising Along The Coasts

US droughts are becoming much more frequent and intense as many areas throughout the country are seeing unusual weather patterns. At the same time, the effects of global warming are causing sea levels to rise by marked amounts all along the US coastal regions.

These two results are now crashing together at the mouth of the Mississippi River in Louisiana. The low flow from the river is allowing salt water to push up from the Gulf of Mexico mixing with the Mississippi’s fresh water. This, experts note creates a lot of adverse effects. Including a threat to fresh drinking water normally pulled from the river.

The US Army Corps of Engineers Will Dredge Sediment Creating a Dam

The US Army Corps of Engineers notes that the dam will be formed by dredging sediment from the bottom of the Mississippi River. The dredged material will then create a type of sill that will dam the area. Stopping the dense saltwater from mixing with the low water levels on the Mississippi.

Ricky Boyett, who serves as chief of public affairs for the Army Corps New Orleans District says that the sill will be underwater. Standing at around 40 to 50 feet high in an area with levels around 90 feet. The solution, Boyett notes is designed to be temporary.

A US Geological survey notes that the current Mississippi River flow rate is running low. Especially in areas just north of the sill dam. At a rate just below 200,000 cubic feet per second. Way too slow to keep the saltwater at bay, Boyett says.

“When [the Mississippi River water level] falls below 300,000 cubic feet per second, it doesn’t have enough force to keep the saltwater at bay,” he explains.

This Will Fix The Problem Temporarily, But There Will Be Future Challenges

According to William Sweet, an oceanographer and seal-level expert with the National Oceanic and Atmospheric Administration, these techniques will help. But only in the short term. However, there are still challenges moving forward.

“While we understand it needs to be done, is it sustainable?” Sweet wonders.

“I suspect that as long as (there is) the will and desire to continue to provide flood safety and drinking water availability,” he relates.

“We will move forward as a country to provide this,” Sweet says. “But it’s going to be increasingly challenging due to the pressures of climate change and sea level rise.”