In the summer of 2005, tens of thousands of citizens from the New Orleans area relocated to Houston and other cities in the aftermath of Hurricane Katrina, most of whom never returned to their former home. A substantial number of those evacuees were poor and largely unemployed in the depressed New Orleans-area economy that existed even prior to the destruction of Katrina. Thus, the hope was that those evacuees would be able to improve their living standard by starting anew in economically vibrant areas such as Houston.
Unfortunately, that has not been the case. As this Jacob Vigdor post notes, research on the Katrina evacuees is indicating that the syndrome of poverty is extremely difficult to change:

Should governments help residents of depressed regions move towards more prosperous areas? Evidence from Katrina evacuees suggests that such efforts are likely to fail. The fortunes of long-term evacuees are almost completely unrelated to the characteristics of the cities to which they relocated. [. . .]
What can the world learn from the experiences of Hurricane Katrina evacuees? As indicated in other recent research carefully examining the impact of residential location on employment, moving a poor, undereducated citizen from a declining urban area to the middle of a vibrant economy is not likely to be a quick, cheap way to find him or her a job. While participants in a voluntary relocation programme would almost certainly be exposed to less personal trauma than Katrina evacuees, the survival instinct alone appears to be insufficient to guarantee success. Particularly in nations with social welfare systems more generous than the American model, the result of any such programme seems quite likely to increase, rather than assuage, drains on the public budget in the short-to-intermediate term.