(AP) – Sept. 1, 2008 -- Cartons of food, water, blankets and other supplies to sustain 1 million people for three days were ready to be distributed Monday as FEMA anxiously eyed Louisiana levees to gauge how much damage Hurricane Gustav would wreak.

  Flood barriers in and around New Orleans, which was devastated in 2005 by Hurricane Katrina, were expected to hold this time, Federal Emergency Management Agency Deputy Director Harvey E. Johnson said. But the storm's surge could overflow levees and at least partially flood the city, he said.

  Damage from Gustav "will be a catastrophe by the time you add it all up," Johnson said in an interview with The Associated Press a few hours before landfall, but not as bad as Katrina.

  "We're expecting levees to hold. We're expecting that that people are much, much more prepared," he said. "We don't expect the loss of life, certainly, that we saw in Katrina. But we are expecting a lot of homes to be damaged, a lot of infrastructure to be flooded, and damaged severely."

  Gustav was downgraded to a Category 2 storm by mid-Monday morning. Katrina was a Category 3 storm when it hit the Gulf Coast three years ago, obliterating 90,000 square miles and costing billions of dollars in damages.

  Although all the levees have been strengthened since Katrina, the Corps of Engineers has not completed its plans to prevent or ease flooding in New Orleans, Johnson said.

  "There's no doubt there'll be water that'll accumulate inside New Orleans," he said. "But we just have to watch that, and understand it and not overreact, and gauge how well those levees are holding."

  An estimated 2 million people have been evacuated from Louisiana, but as many as 10,000 remain in the New Orleans area, Johnson said. He said that evacuees who don't have relatives to stay with are in shelters, including some being housed in junior college dormitories away from the anticipated disaster area.

  The government's sluggish and bumbling response to Katrina shocked the world and turned FEMA into a national laughingstock. Follow-up investigations by Congress and the White House concluded that officials at the local, state and federal levels lacked a sense of urgency in preparing for catastrophic disasters.

  The Army Corps of Engineers identified four Gulf Coast areas as particularly vulnerable to large storm surges according to internal administration briefing documents obtained by The Associated Press: Inner Harbor Navigational Canal at Seabrook, Gulf Intercoastal Waterway/Mississippi River Gulf Outlet, Saint Bernard and Harvey Canal.

  Johnson said FEMA has spent the last two years getting ready for the next big hurricane - which turned out to be Gustav. Response officials in Washington and along the Gulf Coast began gearing up last week, "almost as Gustav was born, and people saw the potential size of that storm," Johnson said.

  Over the past five days, he said, responders have been in a "H-minus-120 timeline," double-checking to make sure all supplies, search-and-rescue teams, medical equipment, transportation systems and shelters were ready to move 120 hours before the storm.

  Aside from coordinating evacuation traffic, the government also spirited 3,000 residents from New Orleans by train and 5,000 by airplane, Johnson said.

  "They all were leaving in a fairly well organized, almost managed chaos, which we've never been able to do before," he said. "The last two (years) were such a light season, it really turned out to be a good chance to build and to train."

  "All of us will watch very intently over the next eight-to-10 hours and get a good assessment of what is the damage," Johnson said. "We all recall the visual images of the Coast Guard picking up people off rooftops in Katrina. I don't think we'll see as much of that this year because so many people evacuated very wisely."