It was forewarned

"No one thought the levees would break"-George W. Bush

"The administration of President George W. Bush cut the 27.1 million-dollar budget requested by the Corps of Engineers for improving the levees in 2005 by more than 80 percent to 3.9 million, although Congress finally raised the grant to 5.7 million, compare to 10 million in 2001."-AFP news report

In 2002, the New Orleans newspaper reported (in eery detail) exactly what could happen if the levees broke:
Washing Away (five-part series published June 23-27 2002)