The arrival of hurricane Katrina
On August 29, 2005 Hurricane Katrina landed in the state of Louisiana in the United States of America. Approximately one million people from Louisiana had been evacuated. On August 28 there was 30% chance that Katrina would pass over New Orleans. From the city of New Orleans about 80% of the 500,000 residents left, before the hurricane arrived. Those that stayed behind suffered heavy floods after the dikes breached in many places. Approximately 80% of the city was under water as a result. In some neighbourhoods the water rose several meters high. About 1100 people died. Approximately 100,000 homes were affected, the damage is estimated at 30 billion dollars. (Source: HKV Consultants and TU Delft, 2007. Two years after Katrina.) A number of smaller places in the vicinity were badly hit by the hurricane winds and rain.
Location and overview
of New Orleans.
Source: TU Delft
Louisiana is flat and has a marshy coast. New Orleans is in the Mississippi delta on the Gulf of Mexico, under sea level, next to a large lake, Pontchartrain. The aerial picture shows you the location. (aerial picture). Louisiana has a subtropical climate.
A hurricane is a huge storm with winds that spin round the eye of the storm: a low pressure area where there is almost no wind. A hurricane can only develop above water of at least 26,5 ˚ C warm. Read and hear more about hurricanes here.
Eventually, the hurricane past right by New Orleans. The water in the lakes Pontchartrain and Borgne was surged up so high by the wind that the pressure on the dikes got too much. The damage by the wind and the rain was bad enough, but the real destruction began when the dikes breached in many places and the water flowed into the city.
People who had stayed at home, went to higher parts of town, if they could. Other people drowned or got trapped in their houses. Rescue workers evacuated people from their flooded houses the next days. Some people still refused to leave, because they were afraid of pillage or because their pets could not come with them.
Here, on the website nola.com, you can see where the dikes breached and how the water, step by step, entered the city.