The rapid urbanization and the high rate of population growth and the influx into urban areas result in overutilization of the available limited natural resources. Rural-urban migration is a major cause of population growth in urban areas. The urban populations in the developing world grew at a 3.35 percent rate annually between 1975 and 2007, and the development rate of the rustic populace stayed steady at around one percent. As a consequence of this trend, in 2007 the world’s urban populace surpassed the rustic populace (United Nations, 2008).