Although Mayor Ray Nagin ordered a mandatory evacuation of the city, many people refused to leave or were unable to do so. In Plaquemines Parish, an official described those remaining behind as "gambling with their own lives."  Reasons were numerous, including a belief that their homes or the buildings in which they planned to stay offered sufficient protection, lack of financial resources or access to transportation, or a feeling of obligation to protect their property. These reasons were complicated by the fact that an evacuation the previous year for Hurricane Ivan had resulted in gridlocked traffic for six to ten hours. The fact that Katrina occurred at the end of the month, before pay checks were in the hands of many was also significant.  A "refuge of last resort" was designated at the Louisiana Superdome . Beginning at noon on August 28 and running for several hours, city buses were redeployed to shuttle local residents from 12 pickup points throughout the city to the "shelters of last resort."