WASHINGTON – A chastised Homeland Security Director Michael Chertoff sparred with senators of both parties on Wednesday as he acknowledged “many lapses” in his agency’s response to Hurricane Katrina.

Chertoff told the Senate Committee on Homeland Security and Governmental Affairs that he would do things differently if he had the chance. One thing he would not do: give overall responsibility for the relief effort to Michael Brown, who was director of the Federal Emergency Management Agency at the time.

Brown, who resigned under pressure shortly after the Aug. 29 storm devastated New Orleans and much of the Gulf Coast, has accused Chertoff and White House officials of ignoring his warnings on the day of the storm.

“It is completely correct to say that our logistics capability in Katrina was woefully inadequate. I was astonished to see we didn’t have the capability most 21st century corporations have to track the flow of goods and services,” Chertoff said, promising remedies by the start of the 2006 hurricane season in June.

Chertoff testified as a separate House investigation concluded that thousands of Katrina’s victims could have been spared through better planning and faster action.

The House inquiry titled “A Failure of Initiative” concluded that much death and suffering could have been avoided if the government had heeded lessons from Sept. 11 and taken a more hands-on stance toward disaster preparedness.

Chertoff, one year on the job, acknowledged missteps. He called the storm “one of the most difficult and traumatic experiences of my life.”

He drew criticism from both Republicans and Democrats.

Committee Chairwoman Sen. Susan Collins, R-Maine, said his agency’s performance “must be judged a failure.” She called it “late, uncertain and ineffective.”

Sen. Joseph Lieberman of Connecticut, the panel’s top Democrat, criticized Chertoff for going to Atlanta for a bird flu conference on Aug. 30, the day after the storm roared ashore, instead of rushing to the disaster scene.

“How could you go to bed that night (Aug. 29) not knowing what was going on in New Orleans?” Lieberman asked.

Under Chertoff’s oversight, disaster workers “ran around like Keystone cops, uncertain about what they were supposed to do or uncertain how to do it,” Lieberman said.

Chertoff disputed Brown’s testimony earlier this month that he had notified White House and Homeland Security officials on the day of the storm that levees had failed and New Orleans was flooding.

Instead, Chertoff reiterated earlier statements that he did not realize that levees had been breached until the next day.

“When I went to bed, it was my belief … that actually the storm had not done the worst that could be imagined,” Chertoff said.

Collins told Chertoff “I remain perplexed” about his decision to designate Brown, who as FEMA director had expressed skepticism about being put under the DHS wing, as point man on coordinating the Katrina response.

Chertoff said there was “no reason to doubt his commitment” at the time.

“If I knew then what I know now about Mr. Brown’s agenda, I would have done something different,” Chertoff added.

The hearing was disrupted briefly by a member of the audience who loudly heckled Chertoff, apparently about this week’s end of a FEMA program that paid for hotel rooms for hundreds of homeless evacuees.

“This is un-American,” said the man, as Chertoff sat stoically. “They’re being evicted.”

Chertoff was subdued throughout the hearing, unlike the combative stance taken by Brown.

“There are many lapses that occurred, and I’ve certainly spent a lot of time personally, probably since last fall, thinking about things that might have been done differently,” Chertoff testified.

Sen. Mark Dayton, D-Minn., called FEMA’s problems “just so dysfunctional, or nonfunctional, it’s frightening.”

The House investigative report said that, from President Bush down to local officials, government agencies did little other than react to the catastrophic storm after the fact – even when faced with early warnings about its deadly potential.

“The preparation for and response to Hurricane Katrina should disturb all Americans,” said the 520-page report, written by a Republican-dominated special committee chaired by Rep. Tom Davis, R-Va., and obtained Tuesday night by The Associated Press.

“Passivity did the most damage,” it said.

The report assigned blame to state and local authorities and concluded that the federal government’s biggest failure was in not recognizing Katrina’s likely consequences as it approached.

Recognizing the dangers earlier could have prompted a mobilization for a post-storm evacuation, and aid would have arrived several days earlier, the report said.

It also found that Bush could have speeded the response by becoming involved in the crisis sooner.

Earlier this week, White House homeland security adviser Frances Fragos Townsend insisted Bush was “fully involved” in Washington’s preparations and response to Katrina.

Katrina left more than 1,300 people dead in Louisiana, Mississippi and Alabama, hundreds of thousands homeless and tens of billions of dollars worth of damage. Bush has accepted responsibility for the federal government’s shortfalls, but the storm response continues to generate finger-pointing.

Associated Press writers Douglass K. Daniel and Hope Yen contributed to this report.