Updated Oct 23, 2023 - Energy & Environment

Super fog near New Orleans blamed for massive pileup that killed 7, involved 158 vehicles

Photo shows wrecked cars in the fog on I-55 in metro New Orleans

More than 150 vehicles were involved in a pileup Monday on I-55 near Manchac, Louisiana. Photo: Courtesy of Casey Tusa

At least seven people were killed and 25 injured in fiery wrecks Monday during "super fog" conditions in metro New Orleans, officials said.

  • Super fog is formed when dense fog combines with wildfire smoke, according to the National Weather Service. It dropped visibility to near zero Monday.

Driving the news: At least 158 vehicles were involved in crashes on I-55 near Manchac, which is just outside New Orleans, Louisiana State Police say.

  • First responders continued to search for victims as of 7pm, says Lt. Melissa Matey of the State Police.
  • Matey said it's possible the death toll will grow.
  • They are waiting for a damaged tanker truck carrying hazardous liquid to be removed before they can fully access all the vehicles.
  • She also said "many victims" sought medical assistance on their own and there's not a total count of injured. More than 25 people were taken to hospitals with injuries ranging from minor to critical.

Zoom in: Police ask anyone with missing family members who were driving in the area to call authorities at (504) 471-2775.

Photo shows wrecked cars in the fog on I-55 in metro New Orleans
At least 158 vehicles were involved in pileups on I-55 on Monday, Oct. 23, 2023, near Manchac, Louisiana. Photo: Courtesy of @NSGladiators on X

The big picture: Fires are burning near Bayou Sauvage and Jean Lafitte National Historical Park and Preserve.

  • The fire in New Orleans East is burning underground in forested wetlands between Bayou Sauvage and the Michoud Canal, city officials said Monday.
  • It's burned about 200 acres and "any form of suppression efforts from above the surface has had little to no effect extinguishing the fire," the statement said.
  • New Orleans firefighters are working with the property owner, with the Sewerage & Water Board and the Louisiana Department of Agriculture and Forestry to clear a path so they can use water from the drainage canal to flood the area.
Photo shows the aftermath of a wildfire with smoke visible on the horizon
Firefighters are battling a marsh fire at Jean Lafitte National Historical Park and Preserve. Photo: Courtesy of Jefferson Parish

The Lafitte fire is 52% contained, according to the National Park Service, which operates the park.

  • It affects 147 acres, and fire crews from seven states and four federal agencies are fighting it.
  • The cause of the fire remains under investigation, NPS spokesperson Meredith Hardy tells Axios.

Threat level: In addition to contributing to low visibility, the smoke is polluting the air.

  • The air quality fluctuates throughout the day. Check it for your ZIP code at AirNow.gov.
  • Older adults, children, teens and people with heart or lung disease are encouraged to take extra precautions, such as limiting outdoor time when pollutants are high.
  • Free N95 and KN95 masks are available this week at some libraries and recreational centers. (full list)

How to help: Give blood, authorities urge.

  • "It will help replenish supplies that are being drained today to care for the wounded," Gov. John Bel Edwards said in a statement that offered prayers for those hurt and killed on I-55.

What's next: Another dense fog advisory is in effect from 3am to 10am Tuesday in southeast Louisiana, according to the National Weather Service.

  • Visibility could drop to near zero again where fog mixes with smoke, the advisory says.
  • Several schools in New Orleans are delaying start times on Tuesday, citing the hazardous driving conditions.
  • Sections of I-55 remain closed as of 6am. Check traffic.

This story has been updated with new details throughout.

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