ABSTRACT
Urbanization affects different aspects of the environment, especially the quantity and quality of water, soil, and air resources. Urbanization can be characterized as an increase in human population density, which leads to an increase in per capita consumption of natural resources and extensive modification of the natural landscape. This will create a built-up environment that is not usually sustainable over the long term and often continues to expand into natural areas (McDonnell and Pickett, 1990). The landscape alterations accompanying urbanization tend to be more long-lasting impacts than other factors. Generally, in urbanizing watersheds, water pollution and stormwater runoff are related to human habitation and the resultant increase in human land uses. The main focus of this chapter is on the effects of urbanization on water quality and the impact of urbanization on ecosystems. Some sections of this chapter are about the impacts of urban areas on the atmosphere and groundwater. Air pollution in urban areas is one of the main impacts of urbanization and a major source of acid rain in urban areas. Another main pollution source of surface water and groundwater in urban areas is stormwater. Stormwater causes considerable pollution of receiving waters. The stormwater in urban areas washes off all pollutants on the land surface during and after precipitation. These pollutants move through the drainage system and discharge to the receiving waters. There are many concerns about the faith of the pollution loads of stormwater as a major component of the urban water cycle. Therefore, a selection of this chapter is devoted to urban stormwater quality modeling.
