Committee member Rep. Chris Shays, R-Conn., said: "The president was clearly misinformed. We had a tabletop exercise -- Hurricane Pam -- that predicted at a level 4 [hurricane], the dam was going to be breached."
Yet Bush, in a Sept. 1 interview with ABC News' Diane Sawyer, said he didn't think that anyone knew that the New Orleans levees could be breached, forcing many of the city's residents from their homes.
"If this is what happens when we have advance warning, we shudder to imagine the consequences when we do not," the report says, referring to a possible terror attack. "Four-and-a-half years after 9/11, America is still not ready for prime time."
Hurricane Katrina killed 1,321 people, including 1,072 in Louisiana. It displaced about 2 million people and caused more than $150 billion in damage.
"The White House was clearly in a fog," Shays said. "Chertoff, the head of Homeland Security, was clearly detached. He didn't even go to New Orleans 'til Wednesday; then you have [FEMA Director Michael Brown], who was clueless and negligent."
The reports say that Chertoff convened an interagency board of experienced strategic advisers on Aug. 30, rather than Aug. 27, when he should have. Katrina hit New Orleans on Aug. 29. It also says that Chertoff designated the untrained Brown to manage the disaster.
"It just stood and watched it fail," said Shays, referring to the Department of Homeland Security. If Chertoff had declared Katrina "a catastrophic event and what that would have done is it would have sent things to this area before we were asked by the governor and the mayor and they obviously asked us too late."
Shays also said the federal government mismanaged the way relief came to the hurricanes' victims. Money was wasted on tattoos, bail bondsmen, even sex toys.
"We were sending so much money that the control just disappeared," he said.
ABC News' Zach Wolf, Martha Raddatz and The Associated Press contributed to this report.