Saltwater intrusion leads to water advisory in Baldwin
Louisiana’s battle with saltwater intrusion into water supplies touched St. Mary Parish this week.
Water and Sewer Commission No. 4 in the Baldwin area issued a drinking water advisory Tuesday, citing high levels of salt in water moving up the Charenton Drainage and Navigation Canal from West Cote Blanche Bay.
The advisory is not a boil order, the commission said in its advisory.
The Environmental Protection Agency classifies saltwater intrusion as a secondary contaminant, the commission said. It “could affect the taste, odor and color of drinking water.”
People on low-sodium diets because of kidney disease or high blood pressure “should pay special attention to sodium (salt) levels in their drinking water,” the commission said.
The Governor’s Office said salt water may also cause corrosion in components of public water systems.
The EPA’s maximum acceptable level is 250 milliliters of salt per liter, and District 4 water has exceeded that level, the commission said.
No other water districts or municipalities in St. Mary have reported excessive saltwater levels in their water systems.
Patterson’s city government posted a Facebook notice quoting Water Plant Supervisor Sharon Gillum as saying no problems have been found in the city’s water supply
She said the Louisiana Department of Health has collected samples and is monitoring the water supply.
Salt water intrusion has been a concern in south Louisiana since at least November 2022, when high levels of salt were detected in the Plaquemines Parish water supply near Boothville.
The problem has been blamed largely on droughts in the Mississippi and Ohio valleys, which reduced the level of the Mississippi River and allowed salt water to move upstream.
Through October, the saltwater “wedge” is expected to move up river, reaching Dalcour by Oct. 15, Gretna by Oct. 24 and East Jefferson Parish by Oct. 29.
Local authorities and the U.S. Army Corps of Engineers have come up with a variety of solutions, including an underwater “sill” to block the salt water in Plaquemines; piping freshwater from farther north on the river; desalinization; and diluting the salt water with fresh water carried in by barges.
At Gov. John Bel Edwards’ request, the Biden administration has declared a federal disaster, which will make federal resources available for mitigation efforts.