It was among the greatest of natural disasters to ever strike the United States. The central pressure at landfall was mb , which ranked 3rd lowest on record for US-landfalling storms behind Camille mb and the Labor Day hurricane that struck the Florida Keys in mb. Katrina also reached a minimum central pressure of mb at its peak, ranking 4th lowest on record for all Atlantic basin hurricanes.
The vicious storm killed over 1, people, disrupted thousands of lives over tens of thousands of square miles, and damaged or destroyed , homes. Damage estimates exceeded billion dollars. Many sheltered in their homes or made their way to the Superdome, the city's large sports arena, where conditions would soon deteriorate into hardship and chaos. Katrina passed over the Gulf Coast early on the morning of August Officials initially believed New Orleans was spared as most of the storm's worst initial impacts battered the coast toward the east, near Biloxi, Mississippi, where winds were the strongest and damage was extensive.
But later that morning, a levee broke in New Orleans, and a surge of floodwater began pouring into the low-lying city. The waters would soon overwhelm additional levees. The following day, Katrina weakened to a tropical storm, but severe flooding inhibited relief efforts in much of New Orleans.
An estimated 80 percent of the city was soon underwater. By September 2, four days later, the city and surrounding areas were in full-on crisis mode, with many people and companion animals still stranded, and infrastructure and services collapsing. The city of New Orleans was at a disadvantage even before Hurricane Katrina hit, something experts had warned about for years , but it had limited success in changing policy.
The region sits in a natural basin, and some of the city is below sea level so is particularly prone to flooding. Low-income communities tend to be in the lowest-lying areas. Just south of the city, the powerful Mississippi River flows into the Gulf of Mexico. During intense hurricanes, oncoming storms can push seawater onto land, creating what is known as a storm surge. Those forces typically cause the most hurricane-related fatalities.
As Hurricane Katrina hit, New Orleans and surrounding parishes saw record storm surges as high as 19 feet.
Levees can be natural or manufactured. They are essentially walls that prevent waterways from overflowing and flooding nearby areas. New Orleans has been protected by levees since the French began inhabiting the region in the 17th century, but modern levees were authorized for construction in after Hurricane Betsy flooded much of the city.
The U. Army Corps of Engineers then built a complex system of miles of levees. Yet a report by the. Corps released in concluded that insufficient funding, information, and poor construction had left the flood system vulnerable to failure.
Even before Katrina made landfall off the Gulf, the incoming storm surge had started to overwhelm the levees, spilling into residential areas. More than 50 levees would eventually fail before the storm subsided. While the winds of the storm itself caused major damage in the city of New Orleans, such as downed trees and buildings, studies conducted in the years since concluded that failed levees accounted for the worst impacts and most deaths.
An assessment from the state of Louisiana confirmed that just under half of the 1, deaths resulted from chronic disease exacerbated by the storm, and a third of the deaths were from drowning.
Hurricane death tolls are debated, and for Katrina, counts can vary by as much as Collected bodies must be examined for cause of death, and some argue that indirect hurricane deaths, like being unable to access medical care, should be counted in official numbers. Hurricane Katrina was the costliest in U. Oil and gas industry operations were crippled after the storm and coastal communities that rely on tourism suffered from both loss of infrastructure and business and coastal erosion. An estimated , people were permanently displaced by the storm.
Demographic shifts followed in the wake of the hurricane. The lowest-income residents often found it more difficult to return. The heavy death toll of the hurricane and the subsequent flooding it caused drew international attention, along with widespread and lasting criticism of how local, state and federal authorities handled the storm and its aftermath. The storm initially formed as a tropical depression southeast of the Bahamas on August By the evening of August 25, when it made landfall north of the Broward-Miami-Dade county line, it had intensified into a category 1 hurricane.
After passing over Florida, Katrina again weakened, and was reclassified as a tropical storm. But over the Gulf of Mexico, some miles west of Key West, the storm gathered strength above the warmer waters of the gulf. On August 28, the storm was upgraded to a category 5 hurricane, with steady winds of mph. In this satellite image, a close-up of the center of Hurricane Katrina's rotation is seen at a. EST on August 29, over southeastern Louisiana. Katrina made landfall that morning as a Category 4 storm with sustained winds in excess of mph.
On the morning of August 29, , Katrina made landfall around 60 miles southeast of New Orleans. Within an hour, nearly every building in lower Plaquemines Parish would be destroyed. Winds of mph and storm surges of 28 feet devastated much of Biloxi and Gulfport, Mississippi. Army Corps of Engineers, which administered the levees, received a report that water had broken through the concrete flood wall between the 17th Street Canal and the city.
The Industrial Canal was later breached as well, flooding the neighborhood known as the Lower Ninth Ward. By late afternoon, the breaching of the London Avenue Canal levees had left 80 percent of New Orleans underwater.
Still, about , people were trapped in the city when the storm hit , and many took last-ditch refuge in the New Orleans Superdome and the Ernest J.
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