As Ida hits, New Orleans relies on improved levees to prevent Katrina-like devastation
Hurricane Ida is bearing down on New Orleans, Louisiana, exactly 16 years after Hurricane Katrina devastated the city — but experts say the levees protecting the area are more prepared to withstand its impacts.
Ida — a Category 4 hurricane — was located 45 miles southwest of New Orleans and 70 miles south-southeast of Baton Rouge, Louisiana, as of 4 p.m. CDT Sunday with maximum sustained winds of 130 mph. according to the National Hurricane Center. It was moving northwest at 10 mph.
The “extremely dangerous” storm made landfall in southeastern Louisiana on Sunday afternoon.
Ida was moving northwestward over southeastern Louisiana as of 4 p.m. and bringing extreme winds, catastrophic storm surge, heavy rain and flash flooding to the area, the hurricane center says. Officials in some areas in its path — including parts of New Orleans — ordered residents to evacuate ahead of the storm.
Hurricane conditions are expected to spread further inland Sunday night.
Ida is one of the most powerful storms to hit the area since Hurricane Katrina and will test the 350 miles of levees, flood walls and other storm protection structures around New Orleans that were enhanced following Katrina, The New York Times reports.
Hurricane Katrina
On Aug. 29, 2005, Hurricane Katrina made landfall near New Orleans as a Category 3 storm.
The storm, the costliest to ever impact the United States, devastated New Orleans and other areas within its path, according to the National Weather Service. It was one of the five deadliest hurricanes to hit the country — killing more than 1,800 people.
“Considering the scope of its impacts, Katrina was one of the most devastating natural disasters in United States history,” the weather service says.
The levees, or walls that are designed to prevent storm surge from flooding a city, that separate New Orleans from Lake Pontchartrain failed as a result of the storm — leading to catastrophic flooding and heightening the loss of life and damage caused by Katrina, the NWS says.
By Aug. 31, 80% of New Orleans was under flood waters.
‘Not the same state we were’
After Hurricane Katrina, the U.S. spent $14.5 billion on levees, pumps, seawalls, floodgates and drainage to provide improved storm surge and flooding protection to New Orleans and surrounding areas, The Associated Press reports.
The levees, including those that breached during Katrina, were reinforced with concrete and other measures, and are built high enough to protect against the water levels of a 100-year storm, or a storm that has a 1% chance of happening every year, according to The New York Times.
“We’re not the same state we were 16 years ago,” Louisiana Gov. John Bel Edwards said Saturday, referring to the improved federal levee system, according to the AP.
But officials have said that Hurricane Ida will still test the flood protection system. On Friday, New Orleans issued a mandatory evacuation for areas outside of the levees and a voluntary evacuation for those inside the levees.
The levels of storm surge projected from Hurricane Ida could come over the levees in some areas. But “there does not appear to be any danger of storm surge coming over the levees on the east bank,” which makes up most of New Orleans and which is where the levees failed during Katrina, officials with the Army Corps of Engineers’ New Orleans District told the AP.
The NWS has also said that “overtopping” of local levees is possible outside of the Hurricane and Storm Damage Risk Reduction System where “local inundation values may be higher.”
“We are testing a different part of the flood protection in and around southeast Louisiana than we did in Katrina,” Barry Keim, a professor at Louisiana State University and Louisiana State Climatologist, told The Times. “Some of the weak links in this area maybe haven’t been quite as exposed.
The levees, however, are designed to overtop.
“It’s a different system than we had in Katrina. By it being designed to be overtopped, we won’t have the erosion and the scouring that leads to breaching,” Ricky Boyett, spokesperson for the U.S. Army Corps of Engineers in New Orleans, told NOLA.com. “Once that water recedes you’ll still have a levee there. There’s a big difference between a breach where water is running uncontrolled into an area and water coming over the top for a brief period of time.”
This story was originally published August 29, 2021 at 12:35 PM with the headline "As Ida hits, New Orleans relies on improved levees to prevent Katrina-like devastation."
