Corps Begins Barging Water To Communities Impacted By Salt Water

All eyes in the greater New Orleans region remain on a wedge of salt water pushing its way up the Lower Mississippi River from the Gulf of Mexico, threatening the fresh water supply for communities on both banks of the river.

With the river near 3 feet at the Carrollton Gage in Uptown New Orleans and the flow rate at Belle Chasse, La., around 150,000 cubic feet per second (cfs.), salt water from the Gulf, more dense than fresh water, is able to push its way upstream. According to the New Orleans Engineer District, a flow of 300,000 cfs. is needed to keep salt water flushed out of the Mississippi River.

For the past week, the leading edge (or toe) of the wedge has remained near Mile 69.4, about 5 miles above the sill the Corps has built to help slow its spread and about 5 miles south of Belle Chasse, the most populous city in Plaquemines Parish.

The Corps’ construction of an underwater “sill” at Mile 63.8 is about 62 percent complete, district officials said at an October 5 press conference. The project involves raising 2,200 feet of sill to a depth of -30 feet; the sill will have a “notch” in the middle to allow deep-draft ship traffic to transit. Although some salt water will continue to move upriver over the sill, the higher-salinity water stays at deeper depths and will be blocked from further migration.

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Following a federal emergency declaration for the parishes of Jefferson, Orleans, St. Bernard and Plaquemines, both Jefferson Parish and Orleans Parish are working to execute contracts to lay pipelines along the river to connect vulnerable water intakes to the river farther upstream, away from where the wedge is expected to reach in the coming weeks. The estimated cost for each parish’s pipeline plan is between $150 million and $250 million.

For St. Bernard and Plaquemines parishes, governments have turned to trucking in bottled water, tying into other municipalities’ water supplies, securing reverse osmosis systems and barging in fresh water in order to dilute water at treatment plants.

The New Orleans District began barging water through a partnership with local towing companies on October 1 with the delivery of 500,000 gallons of fresh water delivered to the Port Sulphur Water Treatment Facility in lower Plaquemines Parish. Magnolia Fleet’s mv. Lucille Brooks assisted with that delivery. The mv. Adeline, also part of Magnolia Fleet, and Marquette’s mv. Randy Eckstein are also involved in the effort, according to a statement from Magnolia Fleet.

“This water can be mixed with water at the intake to dilute salinity content to levels safe for water treatment,” according to the announcement from the New Orleans District. “Additional barges will be delivered as the need for upriver fresh water occurs. USACE anticipates delivering water to the Port Sulphur and Pointe à la Hache facilities during the following week.”

According to the Environmental Protection Agency (EPA), for drinking water to be safe to consume, the chloride level has to be below 250 parts per million (ppm).

The amount of water barged daily will depend on the need, the Corps said, and the agency is working toward having the capability of delivering 36 million gallons of water per day. Ricky Boyett, public affairs chief for the New Orleans District, said the effort to secure fresh water supplies during low water events has been in the district’s wheelhouse for decades.

“We did barge water in 1988 and 2012,” Boyett said. “We are able to support the barging and procurement of [reverse osmosis] systems through drought assistance under the Flood Control and Coastal Emergencies authority (PL84-99).”