250 Billion dollars for katrina relief

According to CNBC, Louisiana is asking the federal government for a quarter of a trillion dollars to help rebuild the city. An important question many people are asking is, "where is this money coming from?"

How do you think the economy will react if 225 billion dollars is used to help rebuild Louisiana? More importantly, where is this money coming from, and is it worth it, economically, to rebuild an entire city that poses the risk to be washed to ruins in the future?