Hurricane Katrina Aftermath

This satellite image provided by DigitalGlobe shows an overview of the upper end of New Orleans ...March 9, 2004 before the aftermath of Hurricane Katrina

This satellite image provided by DigitalGlobe shows an overview of the upper end of New Orleans as it meets Lake Pontchartrain, (at the top of the image)...Flooded streets can be seen throughout the image. The Mississippir river can be seen in the lower right hand portion of the image. (AP Photo/DigitalGlobe)

This satellite image provided by DigitalGlobe shows the Biloxi, Mississippi coast Wednesday Aug. 31, 2005 in the aftermath of Hurricane Katrina.(AP Photo/DigitalGlobe)

Troy Lee, left, embraces his friend Bay St. Louis, Miss., police officer Joel Wallace after discovering he had survived Hurricane Katrina

Dale Graham gathers supplies from a Wal-Mart store for victims of Hurricane Katrina on Wednesday...in Waveland, Miss. Graham said store officials had given him permission. The store was damaged by the hurricane. (AP Photo/Ben Sklar)