The president said after discussing storm recovery efforts with his Cabinet at the White House, "Bureaucracy is not going to stand in the way of getting the job done for the people."
"Governments at all levels failed," said Sen. Susan Collins, R-Maine, in her announcement that the Senate Governmental Affairs Committee would hold hearings. "It is difficult to understand the lack of preparedness and the ineffective initial response to a disaster that had been predicted for years, and for which specific, dire warnings had been given for days."
The federal calls for investigation came as the Army Corps of Engineers started pumping water out of New Orleans.
Mayor Ray Nagin said it could take three weeks to drain all the floodwater, in addition to several more weeks to remove the wreckage and restore electricity.
Though pumping water out of New Orleans signals a major turning point in the recovery effort, authorities are now preparing for the devastation that the receding waters will expose.
"It's going to be awful and it's going to wake the nation up again," Nagin said.
On Monday, Nagin said the death toll in New Orleans could be as high as 10,000.
Yesterday, the Army Corps of Engineers plugged two major gaps in levees at the London Avenue Canal and the 17th Street Canal. Waters from Lake Pontchartrain had submerged 80 percent of New Orleans, which is below sea level.
After fixing the levees, authorities began Tuesday's task of draining New Orleans. Engineers began using portable pumps assembled close to the lake to reverse the flow of water.
"We intend to take it slowly so we don't overtax the pumps themselves, because they have not been in service for a while," city engineer Gregory Breerwood told the Associated Press.