Hurricane Katrina's destruction was worsened by a catalogue of official mismanagement, neglect and ineptitude, much of it preventable, critics said Wednesday.

From the failure of New Orleans officials to devise a evacuation plan, to the federal government's preoccupation with terrorism over natural disasters, official negligence made Katrina's impact far worse than it had to be, they said.

"I fear that a storm which could have cost tens of billions of dollars may cost more than 100 billion to repair. A storm that could have cost us hundreds of lives will probably cost us thousands of lives," Democratic senator Tom Carper said Wednesday.

Katrina struck on August 29, devastating the Gulf coast of

Mississippi, Louisiana and Alabama.

Much focus has been put on the decision of President George W. Bush's administration to place the Federal Emergency Management Administration (Fema) under the control of the Department of Homeland Security.

After the September 11, 2001 attacks, Fema was downsized, its budget slashed and its autonomy erased, as authorities focused more resources on countering potential acts of terror than natural disasters.

The agency's inspector general warned that Fema risked "losing its identity as an agency that is quick to respond to all hazards and disasters" -- a result that Katrina appears to have been borne out.

Disaster management snafus were complicated by a lack of expe-

rience by top Fema officials with little emergency relief experience. Calls have been made for Bush to sack Fema chief Michael Brown.

In New Orleans, levees designed to keep back flood waters were not properly maintained and reinforced, leaving the city vulnerable to a major storm, experts said.

The Republican dominated Congress this year allotted New Orleans only half the 11 million dollars it sought for flood-prevention projects.

Officials appeared to have been caught off-guard by the ferocity of Katrina, but had no excuse for their complacency.

Max Mayfield, director of the National Hurricane Centre, said he warned about the destructive power of the monster category five storm "way before landfall. It's not like this was a surprise," he said.

Critics also said Homeland Security Secretary Michael Chertoff failed to act with sufficient urgency, waiting until August 30, to invoke a "National Response Plan".

State officials and city leaders in New Orleans were also late in issuing evacuation orders, experts said. Similarly, emergency officials in Mississippi issued mandatory evacuations when Katrina was just hours away from landfall.

Federal officials faltered badly when they herded displaced New Orleans residents into a dangerously overcrowded convention centre without adequate supplies or sanitation, critics said.

Many in New Orleans were too old or infirm to make the trip to evacuation points; others refused to be stay in the centres, complaining that they were uncomfortable, filthy and violent.