As New Orleans this week marks the 10th anniversary of the flooding that followed Hurricane Katrina, Mayor Mitch Landrieu on Monday touted many of its advances since the storm but acknowledged that challenges remain that could take years or generations to overcome.

While the city is making progress in many areas, it will take time for some of the improvements made over the past decade to bear fruit, Landrieu told Jeffrey Goldberg, a writer for The Atlantic magazine, during a symposium held as part of the city’s official commemoration of the flood.

Landrieu cited schools as an example, noting the massive effort — fueled by $1.8 billion in federal money — to repair or rebuild dozens of schools, some of which were in deplorable condition even before the storm. But, he noted, it will take far longer for any gains from improvements to the education system to show a lasting impact as the children educated in those schools grow up and reap the benefits.

“It actually takes time to rebuild institutions so human beings can take advantage of institutions and over generations do better,” Landrieu said.

The daylong series of panels kicked off a week of events sponsored by the city, various think tanks and community groups commemorating the 10th anniversary of the city’s flooding. The Sheraton Hotel on Canal Street, the center for the city’s events, bustled with reporters, speakers and residents throughout the day.

As described by Landrieu, the events — culminating with a commemoration Saturday in the Smoothie King Center — have three purposes: remembering the tragedy and the more than 1,800 people who lost their lives; thanking the individuals and groups that helped the city; and showing off how far New Orleans has come since 2005.

“I never for one second, and I don’t think most people in New Orleans, felt anything other than sure that somehow, some way our city was going to come back,” Landrieu said.

The challenge for the city is to figure out how to “keep the momentum up,” he said. And while he praised the city’s collective spirit in the years since the disaster, he warned of divisiveness as the city moves forward.

“The big danger we have in this city is the further we get away from Katrina and the further out of stress we get and the further out of a life-or-death situation, we will have a tendency to go back to all the small little fights we have and lose the overarching arc,” Landrieu said.

Pointing to New Orleans’ population decline since the middle of the last century, which saw the city shrink from 630,000 residents in the 1960s to about 455,000 in 2000, Landrieu contrasted that with the growth the city has seen since Katrina.

The latest census estimate put the city’s population at 384,320 residents, still well short of its prestorm figure but continuing to rise slowly each year.

While that has created issues with affordable housing and gentrification, Landrieu said the city is working to solve those through incentives, zoning and other policies.

Those issues come with growth but are less difficult to deal with than the problems of a city with a dwindling population and tax base, he said.

“You can argue about which problem is better. I’d rather have the growth problem than the shrinking problem,” Landrieu said.

Follow Jeff Adelson on Twitter, @jadelson.