Monday 8/29, early morning: hurricane strikes
Monday 8/29, later that morning: Fox might have broadcast news of the break(s)
Monday 8/29, early afternoon: breaches reported to NO authorities 
Monday 8/29, 6pm : confirmed in a summary distributed by the Louisiana Office of Homeland Security and Emergency Preparedness 
Monday 8/29, "later in the day" : Blanco finds out 
Tuesday 8/30, midnight to 1am: CNN broadcasts a live report on the breach(s) 
Tuesday 8/30, late morning: DHS head Michael Chertoff finds out about the issue 
: two blog reports: here and here
: "News of levee breach hit D.C. late":
Federal and state emergency officials knew by early evening on the day that Hurricane Katrina made landfall that New Orleans' levees had ruptured and that much of the city was inundated with water, documents turned over to congressional investigators by Gov. Kathleen Blanco's administration show.
But that critical information did not make it up the chain of command to the U.S. Department of Homeland Security until more than 15 hours later, a delay that some Louisiana officials believe compromised the effort to rescue people stranded by floodwaters.
The breach of the 17th Street Canal levee, which was reported to New Orleans authorities early on the afternoon of Aug. 29, was confirmed by the Louisiana Office of Homeland Security and Emergency Preparedness in a 6 p.m. summary distributed to state and federal emergency officials in Baton Rouge.
"No power, 911 system down, EOC (emergency operations center) on emergency power and cell phones," the summary said. "Entire city flooded, except French Quarter/West Bank/Business district."
Farther down, in bold type, the summary report notes three breaches in the New Orleans area, including the 17th Street Canal...
FEMA Director Michael Brown, who was in Baton Rouge that day, would have had access to the summary, as did other state and federal officials.
Mark Smith, a spokesman for the state Office of Homeland Security and Emergency Preparedness, said it would have been clear to anyone who had read the summary what was happening in New Orleans. "Her (Blanco's) staff and our staff and the FEMA staff on site . . . all know the implications of any levee in Louisiana going down," Smith said.
But Homeland Security Secretary Michael Chertoff did not find out about the flooding until late Tuesday morning. Russ Knocke, a spokesman for Chertoff, said he doesn't know why the information wasn't conveyed sooner.
"I can't speak for Michael Brown. I can't tell you what happened with that information when . . . it was presented to Mike," Knocke said. "I can just tell you that from our part in Washington, D.C. . . . it was an extraordinarily frustrating period because we simply lacked visibility. That was a result of inadequate information from the field."
Knocke declined to speculate on whether the federal response would have been quicker had Chertoff understood the gravity of the situation sooner. "That's like asking someone to go back and play armchair quarterback," he said...