Five years after Hurricane Katrina made landfall in New Orleans, La., the people there are still working to rebuild their lives. The anniversary of the country's worst natural disaster was an opportunity to look back and learn some important lessons.

The spirit of New Orleans was reflected in parades and memorials services throughout the city. As much progress that has been made, for some it's still not enough.

"It's been five years," said Katrina survivor Oliver Fletcher. "Slow, slow progress."

In the wake of the storm, the U.S. Congress set aside $20 billion for hurricane relief. More than a quarter of that money has yet to be spent. It's held up in bureaucratic red tape.

"The federal government didn't stay and do everything they could," said Sen. Mary Landrieu, D-La. "The federal government didn't make it easy. They made it very, very difficult."

The Federal Emergency Management Agency, FEMA -- heavily criticized for failures in the aftermath of Katrina -- is changing. Its administrator said the agency has learned to adapt, focusing more on outcomes rather than procedures.

However, Michael Brown, former director of FEMA, said the federal government is too big to respond well to catastrophic disasters. It is a fact some locals know first hand.

"Eighty, ninety percent of the folks that came into town were faith-based organizations," said Lou Rizzardi, Pass Christian, Miss. resident. "I do not think we would have accomplished what we did in the time that we did without their support."