** FILE ** In this 2011 file photo, one firm swipe from an excavator demolishes a New Orleans house damaged in Hurricane Katrina. Preservationists and HBO, which uses several such ramshackle houses in ads for "Treme," tried but failed to save them. (Associated Press)

** FILE ** In this 2011 file photo, one firm swipe from an excavator demolishes a New Orleans house damaged in Hurricane Katrina. Preservationists and HBO, which uses several such ramshackle houses in ads for "Treme," tried but failed to save them. (Associated Press)