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An oil rig that broke loose during Hurricane Katrina is wedged under the Cochrane Bridge in Mobile, Alabama. Rescue crews worked frantically to save hundreds of people trapped by floodwaters from Hurricane Katrina, which devastated the US Gulf Coast states of Louisiana, Mississippi and Alabama and reportedly left dozens of people dead.(AFP/Stan Honda)
Residents walk through floodwaters on Canal Street in New Orleans on Tuesday, Aug. 30, 2005, after Hurricane Katrina devastated the Louisiana and Mississippi coasts when it came ashore on Monday. (AP Photo/Bill Haber)
New Orleans residents ride in a boat and walk through floodwaters that besiege the Crescent City on Tuesday, Aug. 30, 2005. Hurricane Katrina devastated the Louisiana and Mississippi coasts when it came ashore on Monday. (AP Photo/Bill Haber)
A toppled brick wall is seen in the French Quarter after Hurricane Katrina hit New Orleans, Louisiana. The storm missed hitting New Orleans directly, but caused massive damage, flooding city streets and battering the roof of the city's Superdome stadium.(AFP/Getty Images/Mario Tama)
Man paddles near two half-submerged houses in the Garden district of New Orleans. rescuers searched flooded neighborhoods and shattered buildings along the trail of devastation Hurricane Katrina left along much of the US Gulf coast.(AFP/James Nielsen)
A dog waits on the side roof of a house to be rescued by workers after Hurricane Katrina in New Orleans, Louisiana. Damage estimates have climbed into the billions of dollars, making Katrina one of the costliest storms ever to hit the United States.(AFP/Getty Images/Chris Graythen)
A young man walks through chest deep flood water after looting a grocery store in New Orleans on Tuesday. (AP/Dave Martin)
New Orleans residents walk through floodwaters that besiege the Crescent City on Tuesday, Aug. 30, 2005. Hurricane Katrina devastated the Louisiana and Mississippi coasts when it came ashore on Monday. (AP Photo/Bill Haber)
A man walks through the flooded Treme area of New Orleans, lying under several feet of water after Hurricane Katrina hit August 29, 2005. Hurricane Katrina ripped into the U.S. Gulf Coast on Monday, battering the historic jazz city New Orleans, swamping resort towns and lowlands with a crushing surge of seawater and stranding people on rooftops. Photo by Rick Wilking/Reuters
The city of New Orleans is inundated with water on Tuesday, Aug. 30, 2005. Flood waters continue to rise in New Orleans after Hurricane Katrina did extensive damage when it made landfall on Monday. (AP Photo/Dave Martin)
Residents wait atop a roof as floodwaters from Hurricane Katrina fill the streets of New Orleans Tuesday, Aug. 30, 2005. Hurricane Katrina did extensive damage when it made landfall on Monday. (AP Photo/David J. Phillip)
Flood waters from Hurricane Katrina fill the streets near downtown New Orleans Tuesday, Aug. 30, 2005 in New Orleans. Hurricane Katrina did extensive damage when it made landfall on Monday. (AP Photo/David J. Phillip)
Looters make their way into and out of a grocery store in New Orleans on Tuesday, Aug. 30, 2005. Flood waters continue to rise in New Orleans after Hurricane Katrina did extensive damage when it made landfall on Monday. (AP Photo/Dave Martin)
Ronald Wood is rescued from his home in New Orleans, Louisiana after Hurricane Katrina made landfall. 2005 is on track to be the worst-ever year for hurricanes, according to experts measuring ocean temperatures and trade winds.(AFP/James Nielsen)
Wal-Mart Stores Inc. on Tuesday said 123 of its U.S. stores, or 3.3 percent, were closed due to Hurricane Katrina, many because of power outages. The closures included both Wal-Mart and Sam's Club stores, a spokeswoman said, adding that two distribution centers were also closed. It was too early to say what financial impact the shutdowns would have. Ninety-seven of the closings were due to power outages. Local curfews were also impacting stores. The company is sending generators to places where power will likely be a continuing issue. A train crossing light downed as Hurricane Katrina hit downtown Gulfport, Mississippi August 29, 2005. REUTERS/Frank Polich
People gather to watch an oil rig that broke apart in drydock during Hurricane Katrina and is stuck on the Cochrane-Africatown USA Bridge over the Mobile River Tuesday Aug. 30, 2005, in Mobile, Ala. (AP Photo/Rob Carr)
Jonathan Harvey wades through flood waters after rescuing his dog 'Cuddles' from his flooded home after Hurricane Katrina struck the Gulf Coast Monday in Gulfport, Miss. (AP/John Bazemore)
David Diaz (L) and his brother Jesus Diaz walk among the rubble of about 30 Sadler Apartments and 100 St Charles Condonimums that were obliterated by Hurricane Katrina August 29, 2005. 'We're looking for our house,' said Jesus Diaz as he clutched a small box, his only possession left. Hurricane Katrina ripped into the U.S. Gulf Coast on Monday, stranding people on rooftops as it pummeled the historic jazz city New Orleans with 100 mph winds and swamped Mississippi resort towns and lowlands with a crushing surge of seawater. Photo by Mark Wallheiser/Reuters
A view of the Sadler Apartments in Biloxi, Mississippi after Hurricane Katrina destroyed them and close to 100 condominiums on the Biloxi waterfront August 29, 2005. Hurricane Katrina ripped into the U.S. Gulf Coast on Monday, stranding people on rooftops as it pummeled the historic jazz city New Orleans with 100 mph (160 kph) winds and swamped Mississippi resort towns and lowlands with a crushing surge of seawater. REUTERS/Mark Wallheiser
A family sits on their porch in the Treme area of New Orleans, which lies under several feet of water after Hurricane Katrina hit August 29, 2005. Hurricane Katrina ripped into the U.S. Gulf Coast on Monday, battering the historic jazz city New Orleans, swamping resort towns and lowlands with a crushing surge of seawater and stranding people on rooftops. (Rick Wilking/Reuters)
People walk amidst the remains of the St Charles Condominiums and Sadler Apartments in Biloxi, Mississippi, August 29, 2005, which were pushed up between the private homes on St Charles Street by the storm surge from Hurricane Katrina. Hurricane Katrina ripped into the U.S. Gulf Coast on Monday, stranding people on rooftops as it pummeled the historic jazz city New Orleans with 100 mph winds and swamped Mississippi resort towns and lowlands with a crushing surge of seawater. Photo by Mark Wallheiser/Reuters
A man riding in an improvised boat paddles past submerged trucks in New Orleans. Rescue crews worked frantically to save hundreds of people trapped by floodwaters from Hurricane Katrina, which devastated the US Gulf Coast states of Louisiana, Mississippi and Alabama and reportedly left dozens of people dead(AFP/James Nielsen)
Adeline Perkins carries her dog, Princess, as Lynell Batiste carries Timmy while Kewanda Batiste and Ulysses Batiste swim through the flood waters from their Lacombe, La. home. (AP Photo/Mari Darr~Welch)
Two residents wade through chest-deep water after finding bread and soda from a local grocery store after Hurricane Katrina came through the area in New Orleans, Louisiana.(AFP/Getty Images/Chris Graythen)
Emergency personnel rescue residents from submerged houses in New Orleans after Hurricane Katrina made landfall causing widespread damage and flooding in New Orleans and other cities on the southern Gulf Coast of the United States(AFP/James Nielsen)
A man puts his baby on top of his car as he and a woman abandon their car after it started to float when Hurricane Katrina hit the Treme area of New Orleans August 29, 2005. The White House said Monday it was willing to use the government's emergency oil stockpile to help refiners hurt by Hurricane Katrina's rampage through the Gulf of Mexico, but that it was too early to decide if or how much crude should be released. The storm slammed into New Orleans on Monday with winds of 135 mph (216 kph), shutting 91 percent of the normal 1.5 million barrels per day of crude oil production in the Gulf Coast region. (Rick Wilking/Reuters)
