What specific effects did urban sprawl have on u. s. society?

well the urban sprawl is basically another word for urbanization. 
It all refers to the migration of a population from populated towns and cities to low density residential development over more and more rural land. 
The end result is the spreading of a city and its suburbs over more and more rural land. In other words, urban sprawl is defined as low density residential and commercial development on undeveloped land. Most of the time, people will move from these areas to try to find better areas to live. This has been the way of the world since the beginning.