- The damage New Orleans faces from Tropical Storm Barry could be made worse because the Mississippi River contains unprecedented water levels.
- One hydrologist said this was the “first time we’ve had a tropical system with water levels on the river this high.”
- Louisiana’s governor said that the river was not predicted to flow over its levees but that a change in the storm’s strength or direction could lead to it do so.
- Barry, which has prompted evacuations in some areas around New Orleans, is expected to make landfall Saturday morning and could do so as a hurricane, testing the city’s defenses that began to be improved after Hurricane Katrina.
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An unprecedented problem could worsen any damage inflicted on New Orleans by Tropical Storm Barry, which is likely to become a hurricane as it hits Louisiana.
The outer bands of the storm began to hit Louisiana on Friday, with evacuations requested in some areas over fears of flooding and what the National Hurricane Center warned could be “life-threatening storm surge.”
But the conditions brought by the storm could end up being worse for the city than what would typically be expected for a storm of its size, because the Mississippi River is higher than normal, with a water level of 16 feet.
CNN quoted Jeffrey Graschel, a hydrologist with the National Weather Service’s Lower Mississippi River Forecast Center, as saying the issue was unprecedented.
“This is the first time we’ve had a tropical system with water levels on the river this high,” he said.
The storm is expected to test the city’s levees on the Mississippi in ways that not even the deadly 2005 Hurricane Katrina did. That hurricane killed more than 1,800 people after levees in New Orleans’ canals failed.
While the Mississippi’s levees held up during that storm, the issue this time is that the flooding from Barry could rise over the levees, which are as low as 20 feet in some places, the National Weather Service warned.
The NWS described flooding as the most significant threat.
Gov. John Bel Edward said that he did not expect the river to rise over the levees but that changes in the storm’s strength or path could change that prediction, the Associated Press reported.
Mayor LaToya Cantrell of New Orleans warned that the city’s water-pumping system could not keep up with the amount of water that is expected to fall on the city, the AP reported. “We cannot pump our way out of the water levels … that are expected to hit the city of New Orleans,” she said.
Barry is expected to make landfall Saturday morning, and it could do so as a hurricane.
“Some strengthening is expected during the next day or so, and Barry could become a hurricane tonight or early Saturday when the center is near the Louisiana coast,” the NWS said on Friday morning.
The storm is expected to bring “flash flooding and river flooding,” according the NWS, which has issued a hurricane warning, which means hurricane conditions are expected in the area, for Intracoastal City, about 175 miles west of New Orleans, to Grand Isle, directly south of the city.
The storm is slow moving, which the NWS said meant more rain and a larger flood threat than a faster hurricane that spends less time in one place.
The service predicted on Friday morning that the storm would bring 10 to 20 inches of rain over southeastern Louisiana and southwestern Mississippi, with a maximum of 25 inches.
The NWS said hurricane conditions were likely to begin Friday night or Saturday morning along parts of the coast.
Evacuation orders have been issued for thousands of people, but not in New Orleans, where the storm is not expected to directly hit.
Storm surge and the tide are expected to cause “normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline,” the NWS said.
As of 4 a.m. CDT on Friday, the storm was about 95 miles, or 155 kilometers, southwest of the mouth of the Mississippi River with maximum sustained winds of 50 mph, or 85 km/h.
US President Donald Trump declared a state of emergency for the state on Thursday night, allowing federal agencies to coordinate disaster-relief efforts.