Katrina was a category 4 storm where storm surges reached over 6 metres in height.
New Orleans was one of the worst affected areas because it is below sea level and protected by levees. The defences were unable to cope with the strength of Katrina.
Impact of Hurricane Katrina
Despite an evacuation order, many of the poorest people remained in the city.
People sought refuge in the Superdome stadium. Conditions were unhygienic, and there was a shortage of food and water. Looting was commonplace throughout the city. Tension was high and many felt vulnerable and unsafe.
1 million people were made homeless and about 1,200 people drowned in the floods.
Oil facilities were damaged and as a result petrol prices rose in the UK and USA.
Response to Hurricane Katrina
Flooding caused by Hurricane Katrina in New Orleans, 2005
There was much criticism of the authorities for their handling of the disaster.
Although many people were evacuated, it was a slow process and the poorest and most vulnerable were left behind.
$50 billion in aid was given by the government.
The UK government sent food aid during the early stages of the recovery process.
The National Guard was mobilised to restore and maintain law and order in what became a hostile and unsafe living environment.