HOUSTON, Sept. 29 (Xinhua) — Salt water moving up the Mississippi River from the Gulf of Mexico is posing a threat to drinking water supplies in and around New Orleans, the largest city in Louisiana, raising concerns about potential lead contamination.
New Orleans Mayor LaToya Cantrell stated in a news release on Friday afternoon that the city’s drinking water is currently safe.
“We have been and will remain in daily, close coordination with local, regional, and state agencies to actively monitor the salt water wedge moving up the Mississippi River,” Cantrell remarked. “The most important thing for residents at this time is to stay informed and remain calm.”
The intrusion of salt water has already affected water systems in Plaquemines Parish and is now approaching various water intakes in the New Orleans metropolitan area, as reported by the office of Louisiana Governor John Bel Edwards.
The leading edge of the salt water is expected to reach St. Bernard on Oct. 19, Algiers on Oct. 22, and Gretna on Oct. 24, according to the governor’s office.
Collin Arnold, New Orleans’ homeland security chief, stated that the problem could render the water undrinkable until at least January, citing projections from the U.S. Army Corps of Engineers.
President Joe Biden approved an emergency declaration in Louisiana on Wednesday to facilitate federal disaster relief efforts in response to the salt water intrusion.
Due to drought in the Midwest, salt water has been slowly flowing north for months, lowering water levels in the Mississippi River enough to allow the Gulf of Mexico water to enter.
Experts warn that salt water can cause corrosion in lead pipes and release heavy metals into drinking water, posing health risks. According to a report from NOLA, approximately 48 percent of the New Orleans water system was installed before 1940, with many pipes over 80 years old. Lead pipes were commonly used until the U.S. banned their usage in 1986.
“We have no idea how many lead pipes remain in the city, but in my field research it was rare for me to find a home without a lead service line,” said Adrienne Katner, a drinking water researcher with the Louisiana State University Health Sciences Center in New Orleans.
The extent of lead contamination may depend on the salt concentrations in the water and the duration of the salt water’s presence in the water systems.
“Any level of lead is harmful,” stated Stephen Murphy, director of Tulane University’s Disaster Management Program. Even after neutralizing the source of corrosion in corroded pipes, they may continue to release lead for months or years.
The Louisiana Department of Health noted that drinking salt water has been linked to cardiovascular diseases, diarrhea, and abdominal pain.
However, city officials caution that it is too early to determine the severity of the contamination as they are exploring solutions to dilute the salt in the water systems, such as constructing a pipeline from further upriver and introducing fresh water by barge.
“Any speculation about impacts is premature, but we are working diligently with top experts at Louisiana Dept. of Health and the Environmental Protection Agency to prepare to increase our frequency of lead testing and address impacts swiftly with a full range of resources,” stated a spokesperson for the New Orleans Sewerage & Water Board.
The agency is currently monitoring salinity levels on a daily basis in the city and neighboring communities downstream.
According to a post on the Army Corps of Engineers website, the intrusion of salt water upstream into the Mississippi River is a naturally occurring periodic condition. The post mentioned that the river’s bottom profile is deeper than the Gulf of Mexico water surface level up to about 15 miles downstream of Natchez, Mississippi. Under normal circumstances, the river’s water flow is sufficient to prevent salt water from intruding upstream. However, when the river’s flow falls below a certain level, salt water may start moving up.
The governor’s office stated in a news release last week that the rate of fresh water flowing down the Mississippi River has been low due to extended drought conditions in Louisiana and across the Mississippi River Valley. Significant rainfall is needed further north to increase the amount of fresh water flowing down the river and flush out the salt.
Credit: The Star : News Feed
