An increase in saltwater in the Mississippi River affecting the drinking water supplies in southeastern Louisiana is a recurring issue. To combat this problem, an underwater levee is being built for the third consecutive year to slow down the intrusion and protect the water intake treatment facilities. The reduced flow of the Mississippi River due to dry conditions has led to saltwater pushing up from the Gulf of Mexico into the river.
Both the U.S. Army Corps of Engineers and the Governor’s Office of Homeland Security and Emergency Preparedness are closely monitoring the situation. Construction of a sill across the river bed began on Monday in Myrtle Grove, located around 30 miles south of New Orleans. This sill, made of river sand, is intended to impede the denser saltwater, which tends to flow along the river bottom. The construction is expected to be finished by October.
Sills have been utilized in similar instances in the region in 1988, 2012, 2022, and 2023. While there are currently no immediate threats to the drinking water supply, additional measures such as using barges to transport fresh water downstream or issuing boil advisories are being considered. Ricky Boyett, a spokesperson for the U.S. Army Corps of Engineers, expressed optimism about the effectiveness of the sill but highlighted that the extent of saltwater intrusion relies significantly on the amount of rainfall in the upper river regions like the Ohio Valley.
The reliance of many communities in southern Louisiana on the fresh water from the Mississippi River underscores the importance of addressing the saltwater intrusion issue promptly. Last year, residents in parts of Plaquemines Parish had to resort to bottled water for an extended period due to elevated salinity levels. In response to the worsening situation in 2023, an emergency declaration was granted by President Joe Biden, providing federal aid to the region, including additional equipment, resources, and funding.
While the current saltwater intrusion has not reached the severity of previous years, officials have preparations in place, including the availability of barges to transport fresh water if needed. Boyett mentioned that the situation is currently under control, indicating a positive outlook in managing the issue effectively.
