Posted on October 28, 2021
The chairman of the Louisiana Coastal Protection and Restoration Authority Board says the planned $800 million Mid-Breton sediment diversion plan will benefit Mississippi rather than harm it.
Chip Kline is the chairman of the Louisiana Coastal Protection and Restoration Authority Board and the Director of Coastal Activities for Lousiana. He says the sediment diversion would be of benefit to Mississippi and the Mississippi Sound’s ecosystem and fisheries.
He also says the sediment diversions will likely create even more marsh habitat than the CPRA’s models predict since the organization decided to be conservative and use the lower end runs of the computer models than utilize some that predict large-scale land addition.
The CPRA wants to build a large concrete structure on the east bank of the Mississippi River and have the river’s floodwaters diverted into the Breton Sound marshes. The Breton Sound connects with the Mississippi Sound to the east.
The project is one of those in the 2017 master plan of the CPRA that would divert flow from the Mississippi River and divert into marshes in the hopes that the river will deposit silt and allow the marshes to heal after years of erosion, saltwater intrusion and other factors that lead to a football field-sized chunk of southeastern Louisiana being lost every 100 minutes.
In 50 years, the sediment diversion is supposed to create 15,831 acres of new marshes, which Kline says it could be as much as 30,000 acres. He says that the CPRA’s experience with other sediment diversion projects, such as Wax Lake Delta Outlet in St. Mary Parish, Pivach Cut and the Caernarvon freshwater diversion in Plaquemines Parish along with the Davis Pond freshwater diversion in St. Charles Parish show that even diversions not intended for wetland building are helping restore marshes.
“Having more of Louisiana on the map is a good thing for the state of Mississippi from a hurricane surge protection standpoint and from an ecological standpoint,” Kline said.
He says more wetlands would also improve harvests for seafood on the Mississippi Gulf Coast since estuaries are vital nurseries for shrimp and fish that are commercially harvested in the northern Gulf of Mexico.
The Mid-Breton Sediment Diversion’s maximum capacity will be 75,000 cubic feet per second when the Mississippi River reaches a flowrate of 1 million CFS. At peak flow, the Mid-Breton project will divert 7.5 percent of the total flow of the river and is supposed to create 15,831 acres of land over the next 50 years.
The funds for the project will come from the $2.544 billion in settlement funds from BP due to the 2010 Deepwater Horizon oil spill.
Critics say that the project will harm oysters, dolphins and other marine life because of the reduction in salinity. Also contributing to the reduction in water quality would be pollution from the Mississippi River, which drains the largest watershed in the United States.
One example cited by project critics as a possible preview of diverting river water into the Mississippi Sound is the opening of the Bonnet Carre spillway. The massive structure been opened 15 times to divert floodwaters into Lake Pontchartrain and through Lake Borgne into the Mississippi Sound.
Kline says the two can’t be compared since the flowrates are vastly different. The Mid-Breton will have a peak flow of 75,000 cubic feet per second, while the Bonnet Carre can have a maximum flow of 250,000 cubic feet per second.
“To think this project will do to coastal Mississippi what the opening of the Bonnet Carre has done is just flawed logic,” Kline said. “We’re (the CPRA) are confident this project will not have a similar impact certainly in the Mississippi Sound.”
Despite that assurance, the Environmental Impact Statement for the Mid-Barataria Sediment Diversion Project predicts “major and adverse effects” on shrimp and oyster fisheries and the dolphin population in Barataria Bay. This project will be located on the west bank of the Mississippi River and replenish the marshes in Barataria Bay.
