Giving New Orleans an adequate new stock of dwellings will take decades.
"New Orleans is a dead city," said Gary E. Stollak, psychology professor at Michigan State University. "Who in their right mind is going to want to build there besides the federal government?"
He and others compared the devastation of the port city to Berlin and other European cities after World War II. The Marshall Plan doled out $12 billion from 1948 to 1951, but many cities still looked war-torn well into the 1960s.
Stollak said he doesn't know whether the United States today has the political will or resources to rebuild New Orleans from the ground up. That may be necessary after a week's worth of water destroyed many of the city's 188,000 occupied housing units.
"From a technical point of view, heck no, the city should not be rebuilt," said Carla Prater, associate director of the Hazard Reduction and Recovery Center at Texas A&M University.
"But we're not technical and economic beings. Cities are important parts of our psyches. Are we ready for New Orleans, the birthplace of so many things, to fade away like Atlantis? I doubt seriously New Orleans will be allowed to die."
Recent disasters -- earthquakes in Kobe, Japan, in 1995, Los Angeles in 1994 and Mexico City in 1984 -- revealed at least a tentative blueprint for recovery.
Thugs may rule New Orleans' streets today, but rebuilding them will be in the hands of bureaucrats, engineers, clerks and politicians. The first step: dull but vital documents usually buried deep in City Hall basements -- sewer maps, flood plain charts, housing inspections, engineering diagrams, blueprints and the like.
"Boring technical data is invaluable," said Aseem Inam, an urban planning professor at the University of Michigan and author of "Planning for the Unplanned: Recovering from Crises in Megacities."
"The most important thing is data gathering. You need to rely on municipal workers, building inspectors from other cities to get a better idea of pre-disaster conditions. It sounds painstaking, but it has to be done on a (house-by-house) basis."
The federal government likely will lead efforts to rebuild major infrastructure but is unlikely to level entire neighborhoods or employ other heavy-handed efforts, Inam said.
Instead, the future of the heart of New Orleans -- its 73 neighborhoods -- lies in the hands of homeowners and landlords. More than half of the city's 100,000 owner-occupied homes were built before 1950, census figures show.
Most are trash, said Mark Stonier, a Birmingham consultant who assesses flood damage for insurance companies.
"The length of time the water has been there, you're going to have to start from scratch," he said.
In Los Angeles, federal, state and city governments offered a package of below-market rate loans for owners of the 7,000 destroyed houses, Inam said. Similar incentives are likely in New Orleans, he said.
Half the city's homeowners don't have flood insurance, though, and insurers will make many decisions about starting over. In New Orleans, 53 percent of the housing units are rentals -- and apartment complexes often aren't rebuilt because banks won't back loans unless landlords can guarantee tenants, Prater said.
But will the city's nearly 500,000 residents return -- especially if they have to leave the city for several months?
Because of its strong cultural heritage and history, New Orleans forms strong bonds with residents, Prater said.
But people need jobs.
"The majority of these people will never come back," said Stollak of MSU.
"Where are these people going to get jobs? Without work, it's meaningless. New Orleans could fade away like so many other cities that have disappeared."
Inam said: "The poor will have no choice. They might not want to come back, but they have to. The second group to come back will be people with long emotional attachments to their neighborhood or family. The rest will go other places."
Reviving tourism key to comeback
The storm also may have destroyed New Orleans' tourism economy, for at least several years.
Host to 10.1 million visitors who spend $5 billion a year, the city ranks fifth nationwide in the number of conventions, according to the New Orleans Metropolitan and Tourism Bureau. Leisure and hospitality are responsible for about 214,000 jobs in Louisiana.
One positive, though, is the city's trademark French Quarter appears to have largely escaped damage. Stollak said many of the casinos and taverns won't rebuild.
"Of course, tourism in New Orleans is dead," he said.
Reviving the city -- and most particularly its commercial life -- will begin with restoration of utilities, communications and myriad businesses.
After a storm as powerful as Katrina, that task is far more complex than just rehanging wires and replacing transformers, said Bill Swank, a spokesman for Florida Power & Light Co.
"It's a massive effort," Swank said. "You've got to dig out the old poles -- or the stubs that are left -- and you've got to put in all new equipment."
Florida Power & Light needed 34 days to restore service to 1.4 million customers after Hurricane Andrew in 1992. After Hurricane Charley cut power to 800,000 customers last year, the system was back up within two weeks.
But the destruction left behind by Katrina is much more extensive.
"A lot of the basic infrastructure is gone. You don't even have anything to work with," Swank said. "You don't even have street signs. You have no idea where you are."
Entergy Corp., the power company that serves 1.1 million customers in New Orleans and part of Mississippi, estimates restoring service to some areas will take more than a month. At the moment, its crews can only get into the few areas that are not flooded.
Having electricity will also be critical to restoring drinking water and wastewater treatment. L.D. McMullen, chief executive and general manager of the Des Moines Water Works in Iowa, said restoring 350,000 people and 1,000 miles of pipeline when the Raccoon and Des Moines rivers overflowed their banks in 1993 took 19 days. New Orleans has a much larger system.
"There's probably a lot of broken pipes in town and broken mains," McMullen said. "You'd have to repair them first."
Once floodwaters have been pumped out and power is available, economic development officials should focus on helping reopen hotels, restaurants and other businesses that cater to tourists, said Jan Svejnar, a University of Michigan business school professor of corporate strategy and expert on economic development in developing countries. That will help draw people back to the city and create a market for other types of businesses.
Then, persuading small businesses to be patient and eventually come back to New Orleans will be the key to creating a thriving downtown after the floodwaters recede.
Oil refineries, so important to the economy of the region and of the country as a whole, already are preparing to reopen. The city's manufacturers and chain retailers have expensive facilities that might be salvageable and big budgets to lean on; most probably will rebuild because moving elsewhere would cost even more.
But it's the small firms -- the kind that could operate anywhere in the country but had chosen to set up shop in New Orleans -- that create the most jobs and determine whether a region is economically successful, experts said. Unfortunately, they are also the businesses that can't afford to remain closed for a year or longer until conditions in the city have improved.
Local, state and federal officials will need to give business owners incentives to rebuild and help them get the resources necessary to do so, said U-M's Inam.
Some businesses will never come back, Inam said. Those that want to will have to wait for enough residents to return so they can have customers and employees again.
One big factor working against New Orleans is that, while downtown and the French Quarter were popular tourist destinations, it had one of the highest poverty rates among large U.S. cities and unemployment was rising.
"History has not been kind to cities where pre-disaster conditions were down," Inam said. "They rarely get better."
Svejnar expects ports to resume operations fairly quickly, which will allow manufacturers in the city's petroleum, petrochemical, shipbuilding and aerospace industries to send and receive goods again. The Port of South Louisiana is the country's busiest, and the port of New Orleans ranks fifth.
"It will be uneven. Some things will come back faster than others," Svejnar said.
"Generally, all around the world, most recovery efforts have been underestimated. I think it will be faster than people realize."