Saltwater wedge updates: Belle Chasse and communities upriver unlikely to see impacts

Belle Chasse is now among the growing ranks of locations in southeastern Louisiana that won’t likely be affected by the saltwater wedge moving up the Mississippi River.

The U.S. Army Corps of Engineers reported this week that salt levels should remain within a range that is safe to drink when — and if — the wedge reaches the area’s water treatment plant.

Pointe à la Hache in Plaquemines Parish, which has already been dealing with the saltwater for weeks, is now the northernmost community that officials expect will see impacts from the wedge, according to the latest forecast. The community is downriver from an underwater sill that the Corps of Engineers built, and then raised, to slow the northward movement of the salt water.

The dense layer of salt water was previously forecast to reach Belle Chasse, also in Plaquemines Parish, by Nov. 30. But the latest forecast now predicts that no communities upriver from the underwater sill will see unsafe levels of salt in their drinking water.

Water treatment plants in Pointe à la Hache and Port Sulphur have been receiving fresh water, brought in from upriver by barge, and mixing it with the water they draw from their intakes in order to dilute the salt content to safe drinking levels.

After receding five miles downriver in mid-October, the wedge has resumed moving slowly north for the second consecutive week. It is now at river mile 68.3, about seven miles south of Belle Chasse.

Officials have stressed that the forecast could change and the wedge could continue moving upriver if expected rainfall fails to arrive.

The saltwater wedge slowly creeping up the Mississippi River is no longer threatening drinking water for Louisiana’s biggest metro area — but officials in Orleans and Jefferson parishes are moving forward with mitigation plans, in case forecasts shift yet again.

Jefferson Parish has installed and completed testing on a pipeline intended to pull in fresh water from upstream to dilute any briny water that might make its way into the drinking water supply, while Orleans Parish has identified a contractor for similar work at its Algiers water plant.

Jefferson has laid 15 miles of flexible pipeline along the Mississippi’s west bank batture, the area between the water and the levee. That system, powered by diesel pumps installed at 3- to 4-mile intervals, is designed to pull fresh water from the river north of Kenner to the West Bank Water Treatment Plant.

Read the whole story.

Belle Chasse, in Plaquemines Parish, is now the northernmost location expected to see impacts from the saltwater wedge moving up the Mississippi River.

The U.S. Army Corps of Engineers said Thursday that salt levels should remain within a safe drinking range at all water treatment plants upriver of Belle Chasse. The forecast has changed expectations for Dalcour, also in Plaquemines, which had been forecast to see higher salt levels starting in mid-November.

“I have cautious optimism for the Metro New Orleans area from Dalcour all the way upriver,” said Matt Roe, a spokesperson for the Army Corps of Engineers.

The latest forecast means Orleans, Jefferson and St. Bernard parishes remain in the clear.

Salt water is expected to reach Belle Chasse around Nov. 30, more than two weeks later than last week’s forecast estimate.

The Army Corps of Engineers has barged roughly 38 million gallons of fresh water to treatment plants in Plaquemines already affected by the wedge, and is ready to do the same in Belle Chasse if needed, Roe said.

The wedge was measured earlier this week at river mile 65.8, about two miles north of the Army Corps of Engineers’ newly heightened underwater barrier, and 10 miles south of Belle Chasse.

For most of October, the dense layer of salt water was stalled behind the sill, after rains in the Midwest created a stronger river flow, pushing it back toward the Gulf of Mexico from its northernmost point at river mile 69.4 in Plaquemines Parish.

As the salty water continues its northward creep, the toe of the wedge is expected to reach as far north as river mile 95, in New Orleans, by the end of the Corps’ extended forecast — but salt levels are expected to remain within safe drinking levels in and around the city, if conditions remain steady.

“We're just really hoping for a steady rainfall over the next few weeks across the [Mississippi River] valley,” Roe said. He said increased rain would help maintain steady rates of water flow and push the wedge back downriver.

Halle Parker

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WWNO

Approaching salt water spurred immediate precautions to protect drinking water in parishes further up the river, where the wedge is no longer a threat.

Meanwhile in Plaquemines Parish, the only area still impacted, residents feel forgotten.

“We're neglected. I mean bar none,” said Jaime Taylor, who lives in Boothville. “It's just that simple.”

Listen here.

St. Bernard Parish is no longer expected to be affected by the saltwater wedge moving up the Mississippi River, joining its upriver neighbors.

The U.S. Army Corps of Engineers reported this week that salt levels should remain within a range that is safe to drink when — and if — the wedge reaches the parish.

The Dalcour water plant, in Plaquemines Parish, is the northernmost water intake officials expect will see impacts from the wedge, according to the latest forecast. The dense layer of salt water is predicted to reach Belle Chasse, also in Plaquemines, on Nov. 13 and Dalcour five days later.

The wedge was previously forecast to reach the two intakes on Oct. 27 and Nov. 1 respectively.

Plaquemines Parish is already mixing fresh water, barged in from upriver, to dilute salt levels at treatment plants to the south, according to officials. The parish plans to do the same at Belle Chasse and Dalcour.

The wedge has been hovering at river mile 63.9 near Myrtle Grove, slowed by the Army Corps of Engineers’ newly heightened underwater barrier, or sill. It’s been there since rains in the Midwest strengthened the Red River’s flow into the Mississippi, and the Mississippi’s flow toward the Gulf — which pushed the wedge back five miles earlier this month.

Officials have stressed that the forecast could change and the wedge could move upriver more quickly as levels on the Red River fall.

New Orleans’ water treatment plant in Algiers is no longer expected to be affected by the saltwater wedge moving up the Mississippi River.

The U.S. Army Corps of Engineers says salt levels should be within the safe-drinking threshold set by the Environmental Protection Agency when — and if — the wedge reaches New Orleans.

The change in forecast is largely thanks to two mitigation efforts: a newly raised barrier in the Mississippi is slowing the wedge. And less water is being diverted from the Mississippi into the Red River. That, coupled with recent rain in the Midwest, has increased the flow of fresh water toward the Gulf.

“Over the past few forecasts we’ve released, the actual flows have been higher on the river, so we’ve been seeing a favorable trend,” the U.S. Army Corps of Engineers’ Matt Roe said in an interview with All Things Considered host Bob Pavlovich on Thursday.

The forecast also pushes back the wedge’s arrival at Belle Chasse and Dalcour water treatment plants in Plaquemines Parish by two weeks — to Oct. 27 and Nov. 1, respectively. Plans are in place to barge freshwater to both communities and provide Dalcour with a reverse osmosis filtration system, Roe said.

The wedge could reach St. Bernard Parish by Nov. 8, though the date is just outside the National Weather Service’s 28-day forecast for the lower Mississippi River.

Thanks to increased river flow, the wedge retreated more than five miles last week, according to the latest field measurement.

Flows have hovered at around 150,000 cubic feet per second over recent months, said Roe, and will need to double to push the wedge back out to the Gulf of Mexico.

Ron Spooner, interim head of the New Orleans Sewerage and Water Board, told city council members Tuesday that rain in the Midwest increased the Mississippi’s flow, pushing the wedge south.

“That is very good news for the entire region,” Spooner said.

The wedge of dense, salty water was at river mile 63.9 on Monday, according to the Army Corps of Engineers. It had been at river mile 69.4, about six miles south of Belle Chasse in Plaquemines Parish, on Oct. 2.

Despite the retreat, Roe said the wedge is forecast to resume its northward creep. Its toe could eventually reach river mile 103, near New Orleans’ Carrollton water treatment plant, past its Algiers facility. Salinity levels at the toe of the wedge remain low, with high-salinity water trailing 15 to 20 miles behind.

While the level of salt in the water that’s expected to reach Algiers should be far below the safe-drinking threshold, it will be higher than usual. The Sewerage and Water Board said in a statement Thursday that it plans to dilute the salt water with added fresh water before it’s treated. Salt levels at the Carrollton plant are expected to stay within typical levels.

The Sewerage and Water Board is still moving forward with plans to build a pipeline to bring fresh water from north of Kenner to the Carrollton plant, if needed. Construction hasn’t started yet, while in Jefferson Parish, part of its temporary line is already laid.

Spooner told council members Tuesday that earlier cost estimates for New Orleans’ pipeline had been revised upward. The cost is believed to be close to $300 million, though it could come down now that the city no longer has to build it quickly.

Councilmember Joseph Giarrusso said at the meeting that some of the funding should come from the federal government — and pointed to reporting from The Times Picayune | The New Orleans Advocate that the Army Corps of Engineers knew that its dredging of the lower Mississippi to facilitate shipping commerce would make saltwater intrusion worse.

He described the four parishes affected by the wedge as the country’s “sacrificial lambs.”

“I think it is completely warranted to expect our federal partners to help contribute,” he said, “given what our sacrifice means for the rest of the nation.”

The U.S. Army Corps of Engineers finished increasing the height of an underwater barrier Wednesday, designed to slow the movement of salt water up the Mississippi River.

The Corps initially constructed the sill in July and it was overtopped by intruding water from the Gulf of Mexico on Sept. 20. Work to heighten the sill started in late September.

Since then, the federal agency has worked to raise the barrier by 25 feet. Most of the underwater structure now sits 30 feet beneath the river’s surface, except for a deeper 625-foot-wide notch to allow ships to pass.

This is the fifth time the Corps has constructed a sill to hold back salt water from advancing upriver. Previous sills were constructed in 1988, 1999, 2012 and 2022.

Salt water could overtop the heightened sill, which is located at river mile 64. The wedge was last measured at river mile 63.9, after rain in the Midwest increased the river’s flow, pushing the wedge five miles downstream last week.

Once there is sufficient rain, river flows will increase enough to push the salt water back out to sea. Those stronger flows will also wash the sill away.

Taxpayers in the four parishes where saltwater intrusion from the Mississippi River has or will impact the drinking water are getting more time to file their returns.

The Louisiana Department of Revenue is granting automatic filing extensions to taxpayers whose primary residences, business, critical tax records or tax preparers are in Jefferson, Orleans, Plaquemines or St. Bernard parishes. All four parishes are within the a federally declared disaster area.

The extensions, which are being granted for up to six months, are available for individual, corporate and partnership income taxes, fiduciary income taxes and corporation franchise taxes.

No action is needed for taxpayers who qualify for the automatic extension.

Taxpayers who do not meet all the criteria for an automatic extension can still apply to the Louisiana Department of Revenue for relief from potential penalties. More information is available from a bulletin the state issued Friday.

Construction is underway on a pipeline that will bring fresh water to Jefferson Parish from further upriver if the saltwater wedge reaches the parish’s water supply.

Contractors started installing flexible “lay-flat” pipes on Wednesday after obtaining approval from the U.S. Army Corps of Engineers. The piping, which looks more like a hose, could bring millions of gallons of water a day to treatment plants on the parish's east and west banks if needed.

Parish President Cynthia Lee Sheng said Thursday that contractors will lay the first 7 miles of the pipeline and then test the system to make sure it works. They'll prepare the remaining 8-mile segment, she said, but will only install it if necessary.

“That, we think, is the most prudent way to handle this, the most scalable way to handle this, and the way to position ourselves so very worst case scenario we’re not caught off guard,” Lee Sheng said.

The wedge’s movement up the Mississippi River has slowed significantly and is now forecast to reach Jefferson Parish in late November at the earliest. The month-long delay means officials in Jefferson and New Orleans no longer have to rush to build brand new pipelines in just a few weeks.

New Orleans will have a lot more time to prepare for the saltwater wedge’s approach than originally expected, according to a new government forecast — and it’s possible the briny water won’t even reach the city’s main water supply.

The new timeline released by the U.S. Army Corps of Engineers Thursday estimates salt water won’t make it to the city’s east bank until early December, if it gets there at all.

Earlier predictions had the salt water reaching New Orleans’ Carrollton Water Treatment Plant on Oct. 28.

It’s now expected to reach St. Bernard Parish on Oct. 28, followed by New Orleans’ Algiers Water Treatment Plant on Nov. 23; and Gretna, in Jefferson Parish, on Nov. 26.

The new timeline doesn’t list dates for three other major plants farther upriver — West Jefferson, Carrollton, and East Jefferson — because they’re beyond the National Weather Service’s Lower Mississippi River forecast, which only extends 28 days.

It does estimate that by the time the wedge reaches those plants, salt levels will be less than 250 parts per million. That level is when the Environmental Protection Agency says water starts to taste salty, but doesn’t necessarily threaten health.

The delay buys parish officials much more time to build pipelines to deliver fresh water to treatment plants from upstream. Jefferson Parish started laying pipes for a temporary line earlier this week, and New Orleans isn’t far behind.

Read the whole story.

If the city’s water gets too salty, New Orleans’ public schools have a plan.

They’ll cover drinking fountains, disconnect water lines from cooking equipment and distribute bottled water to students and teachers.

What they won’t do is close schools.

“I have no expectation that we'll have to shift to any remote learning or anything of that nature,” NOLA Public Schools Superintendent Avis Williams said at a press conference Tuesday. “I do look at that as a worst-case scenario.”

Aubri Juhasz

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WWNO file

Exactly which steps the district will need to take — and when — is still unclear, as city, state and federal agencies race to get ahead of the saltwater wedge slowly moving up the Mississippi River. The river is a major source of drinking water for communities in southeast Louisiana.

Affected parishes plan to deliver fresh water from upstream, by barge and newly laid pipeline, to mix with local water at treatment plants, diluting the salt to levels safe enough to treat.

The layer of salt water, which is heavier than fresh water and moving slowly north along the riverbed, is expected to reach New Orleans’ West Bank in about two weeks.

If efforts to dilute the salt are successful, the city’s water will remain drinkable, and the schools, along with the rest of the city, won’t have to make any changes.

But if they’re unable to reduce the salt to a level that’s safe to treat and drink, school leaders will need to take action.

Read the whole story.

For most people, drinking water contaminated with salt does not pose a significant health risk: The overwhelming taste of salt will simply stop people from drinking an amount that their bodies can’t process.

But that’s not true for everyone, said Dr. Joseph Kanter, Louisiana’s state health officer. The risks of ingesting salt water are far greater for people in certain groups, including infants receiving formula mixed with water, pregnant people and people whose doctors have them on low-sodium diets for conditions like high blood pressure.

Kanter told Louisiana Considered host Diane Mack that he’s keeping his eye on a more serious threat that salt water can pose if it intrudes into the water system. That briny water can corrode pipes made from heavy metals like lead and copper, potentially leaching those metals into the water supply.

“We have old piping infrastructure in this part of the state,” said Kanter. “Lead pipes are still in the ground in many places, cast iron, galvanized fittings, lead solder. All of that is a corrosive risk should the sodium chloride increase.”

To protect residents, Kanter said, officials are planning to increase the amount of testing for levels of heavy metals in the drinking water. He advised everyone in southeastern Louisiana to keep close tabs on water advisories – and switch to bottled water immediately when warnings are issued.

The U.S. Army Corps of Engineers is shipping fresh water on barges to small treatment plants south of Gretna, in anticipation of the saltwater wedge that’s moving up the Mississippi River.

The fresh water will be used to dilute the wedge’s briny water when it’s pulled into the plant to be treated. The Army Corps of Engineers hopes the strategy will keep clean tap water flowing for the communities served by the plants.

But it won’t be possible to barge in enough fresh water to support larger plants in New Orleans and Jefferson Parish, which go through hundreds of millions of gallons of water a day.

Both parishes have decided to build pipelines to draw fresh water from the river north of Kenner. The plans received state approval Friday, and officials are in the process of securing contractors.

Collin Arnold, New Orleans’ director of homeland security and emergency preparedness, told All Things Considered host Bob Pavlovich that bids were due Monday.

Arnold said the city’s sewerage and water board will select a contractor quickly, so pipe — 48-inch PVC — can be laid starting this week.

“They’ll be moving as fast as possible to get this started immediately,” he said.

Read the whole story.

As promised, we’re updating our saltwater wedge guide with more answers to your questions.

New so far this week:

• How salty is our water usually?
• What's the pipeline plan for New Orleans and Jefferson Parish?
• Where's barged water coming from?
• If the federal government shuts down next month, what impact could it have on response to the salt water wedge?

The U.S. Army Corps of Engineers made its first delivery of fresh water by barge to Plaquemines Parish on Sunday, bringing half a million gallons to Port Sulphur’s treatment facility.

About 2,000 residents living in the southern end of Plaquemines went without fresh drinking water for months when the saltwater wedge reached the area in late June. The water was 6.5 times saltier than the Environment Protection Agency deems healthy.

The parish had distributed 1.5 million gallons of packaged water locally by mid-September.

Water delivered Sunday was collected upriver, deep in the water column where there tends to be less contamination from runoff than near the surface. The fresh water will be used to dilute the water already being pumped and treated at the facility as needed.

The Corps plans to barge more water to Port Sulphur and another facility in Pointe à la Hache and expand deliveries to additional locations as more communities are impacted by the saltwater wedge.

The plan — which we detail in our guide — is to dock giant barges alongside each water treatment facility to serve as reservoirs that can then be replenished by dozens of other barges.

But the approach won’t work for larger parishes, since they need a lot more water. Officials in Orleans and Jefferson plan to build pipelines to carry water from an area north of Kenner to treatment plants on both the east and west banks.

In New Orleans, a pipeline designed by the Sewerage and Water Board would deliver water to the Carrollton water treatment plant, which provides 141 million gallons of water to the city each day. The cost to build the pipeline could range from $100 million to $250 million, according to the city’s homeland security chief Collin Arnold. They’re aiming to complete it within a month — just in time for the estimated arrival of the wedge.

Jefferson Parish, meanwhile, is planning its own line, using flexible pipes to carry water 10 and 15 miles downstream to the parish’s two plants. Mark Drews, the parish’s director of public works, said Friday that they hope to start construction this week.

The wedge was last measured at river mile 65.8 on Oct. 20. That's about two miles north of the Army Corps of Engineers’ newly heightened underwater barrier, or sill, and 10 miles south of Belle Chasse.

It resumed its northward creep this week after stronger river flow pushed the wedge five miles toward the Gulf of Mexico earlier this month.

The wedge had previously reached river mile 69.4, about six miles south of Belle Chasse in Plaquemines Parish, on Oct. 2.

Its movement has slowed significantly and the wedge is no longer expected to impact water treatment plants outside of Plaquemines Parish directly.

We’re doing our best to answer your questions about the salt water moving up the Mississippi River.

If you have a question we haven’t answered yet — check out our guide first — reach out to Coastal Desk reporter Halle Parker on X or by email.

Gerald Herbert

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AP

President Joe Biden approved Louisiana’s request for a federal emergency declaration Wednesday, freeing up funding to help the state protect its drinking water, as a saltwater wedge moves up the Mississippi River.

The U.S. Army Corps of Engineers plans to barges millions of gallons of fresh water from higher up the Mississippi to affected water treatment plants. Fresh water will be mixed with local water, diluting it enough to be treated and used.

But officials have warned the barges won’t be able to bring in enough fresh water to include treatment plants on the east bank of New Orleans and in Jefferson Parish.

Now, they’re floating the idea of building a more direct fix: A pipeline that would divert water from upstream.

Collin Arnold, New Orleans Director of Homeland Security and Emergency Preparedness, told City Council members Wednesday the pipeline would draw water from north of Kenner and could eventually be made permanent, providing a solution for future disasters.

The Army Corps of Engineers announced plans earlier this week to heighten an underwater barrier in the Mississippi — that was built this summer and overtopped last week — to give Orleans and Jefferson parishes more time to prepare.

The agency said the improved barrier should slow the salt water wedge by 10 to 15 days. That should buy authorities enough time to build the pipeline before the water arrives, Arnold said.

Officials with the city’s Sewerage and Water Board said the pipeline could cost between $100 and $250 million and that they are seeking federal funding.

"We’re not in a doomsday situation by any means," Arnold said. The situation, he added, is “manageable” — and praised local agencies’ response.

“This has been probably the biggest mobilization I've seen of everyone as a region, understanding that this is, we're not getting out of this.”

Arnold said New Orleans is preparing to deal with the effects of potential salt water through January, based on forecasts from the Army Corps of Engineers. The wedge is projected to reach New Orleans by late October.

What's reverse osmosis? If the water gets too salty, could they close schools?

These are some of the many questions we've received as the saltwater wedge makes its way north, threatening water supplies across four parishes.

To answer these and many others, we've put together a guide — and will keep updating it until the salt water retreats.