New Orleans Mayor Ray Nagin opened the first of a planned series of service centers designed to help Hurricane Katrina evacuees outside Louisiana return to their hometown and rebuild it so it's "no longer a city of haves and have nots."

The city is troubled but ready to welcome them back, Nagin told evacuees at the opening Tuesday of a Houston center run by his office and the city of Houston.

"Let me just be honest with you about the realities of New Orleans," Nagin said. "There is still a lot of devastation in the Lower Ninth Ward and in certain areas of New Orleans East. You may want to consider temporarily moving to a different part of the city until your section is back up and operational.

"For some reason there are powers that be that want to change this city forever. And we can't allow that to happen. We must work together."

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Nagin said New Orleans' levee system has been repaired but won't offer total protection this year. After Katrina hit Aug. 29, levees failed, flooding 80 percent of the city. The death toll in Louisiana alone was about 1,600.

The New Orleans Journey Home Center in Houston, where thousands of evacuees ended up, will provide information about affordable housing, schools, child care, job training, healthcare and small business development.

Tiffany Ross, 29, said daycare and affordable housing will be her most important needs. The hotel worker said she was optimistic but felt government officials at all levels hadn't done enough to help.

"I'm very hopeful there are resources out there to help me return home," she said. "I'm confident of that."

Nagin encouraged New Orleans residents to "make some noise" to get government assistance that will allow them to buy homes instead of renting, and to become entrepreneurs so they can become self-sufficient.

"Let's become one of the most affluent cities in the world ... and that we are no longer a city of haves and have nots," he said. "We want you back in the city of New Orleans as soon as possible because the red beans just ain't the same without you all."