La. diversion threat Miss. oysters?

Freshwater from Louisiana's proposed $800M Mid-Breton Sediment Diversion could pose a major threat to Mississippi Sounds oysters and fisheries, according to a study commissioned by the Mississippi Department of Marine Resources. With diversion waters added to an average of Mississippi River, Lake Pontchartrain and other Mississippi coast rivers and bayous an 11-year record of salinity levels in western Mississippi Sound, near Bay St. Louis, where oysters are grown, drops to unsafe levels for 50-plus days, says Jerry Wiggert, lead author, and associate director of USM's School of Ocean Science and Engineering. Oysters are generally able to tolerate salinity levels of between 5 and 15 parts per thousand. The peer-reviewed study was based on Louisiana’s original plan for the diversion that called for a maximum flow rate of 75,000 cubic feet/second. In 2021, Louisiana announced it was reducing the maximum flow to 50,000 cfs. Wiggert's team has not looked at that lower rate but expects it could result in as much as 21 days of salinity levels below 4 parts per thousand in the western sound, which would still be a threat to oysters. (NOLA.com 02/23/23) Mississippi Sound oysters at risk from Louisiana plan: study | Business News | nola.com