Bush was to be updated on the rebuilding effort and tour part of New Orleans on his 10th trip to the region since the Aug. 29 storm. Afterward, he was flying east to view progress in the Biloxi-Gulfport area of Mississippi, another state hit hard by Katrina.
More than three-fourths of New Orleans was flooded after Katrina tore through, sending water through failed levees that were designed to protect the city from such a fate. Much of New Orleans remains a mess. Demolition of the worst-damaged homes in the hard-hit lower Ninth Ward and Lakeview areas only began this week.
The trip is the president's first to the region since two reports — one by a House committee, the other by the White House — criticized the government's response to Katrina.
One of the worst natural disasters in U.S. history, Katrina killed more than 1,300 people in Louisiana, Mississippi and Alabama, left hundreds of thousands of people homeless and caused tens of billions of dollars in damage.
The visit also comes after the release of video of an administration briefing on the eve of the storm that raised new questions about Bush's involvement in the hurricane planning.
The White House said the trip was not an attempt to make up for the criticism.
"The president made a very strong commitment, and we're following through on that commitment," spokesman Scott McClellan told reporters Tuesday. "He has visited the Gulf Coast a number of times, as have a number of our Cabinet secretaries and other high-ranking officials in the administration, and we will continue to visit the Gulf Coast region."
But the criticism continued.
In Washington, Texas Gov. Rick Perry, a Republican who holds Bush's old job in Texas, said the federal government had turned its back on his state, which bore the brunt of Hurricane Rita. Perry said the government was being more generous to states hit by Katrina than to his, and he demanded an additional $2 billion in post-hurricane funding.
The governors of Louisiana, Mississippi and Alabama also are lobbying Congress for more money to pay for hurricane relief and rebuilding. Total hurricane-related spending on the region is approaching $100 billion.
In New Orleans, the Army Corps of Engineers is working to meet a June 1 deadline — the start of the year's hurricane season — to rebuild the city's flood protection system so it is as good or better than it was before Katrina.
Lt. Gen. Carl Strock, head of the Army Corps, said 100 of 169 miles of the city's damaged levees have been restored. But he acknowledged that won't prevent flooding in low-lying areas if a storm as powerful as Katrina slams the coast this year.
McClellan said the administration is working to make the levee system stronger than before, but that the undertaking is a two- to three-year process.
"Let's keep in mind, when you have hurricane, I don't know of instances when there is not flooding," he said. "So I think that is stating something that could be fairly obvious."
Independent experts also have accused the Army Corps of taking shortcuts to rebuild the levees quickly and of using materials that could leave large sections of the system significantly weaker than before Katrina. Strock denied the allegations.
Before touring the hurricane zone, Bush and wife, Laura, flew to their hometown of Crawford, Texas, and voted in the state's Republican primary. The election featured a campaign for governor and a contested congressional seat in the district where the president lives.