Yet, nonpoint sources of contamination, such as urban runoff, can be just as damaging. Storm runoff from metropolitan areas may carry a wide range of pollutants into rivers, which then transport pesticides, metals, chlorinated hydrocarbons, and other contaminants to the sediments of lakes and estuaries.
Urban runoff is a very significant source of water pollution heavily populated urban areas.
Focus Researchers at Rice University are examining runoff from the Houston area as it makes its way to Galveston Bay, characterizing particles and quantifying contaminant transport. Information acquired through this study will be relevant to other urban areas, and will serve an important role in analyzing the environmental impact of urban growth. To date, most research on particle transport has focused on particles larger than 10 micrometers in diameter. Knowledge of whether and how these particles aggregate is crucial to developing a strategy to control runoff pollution. Data from both laboratory experiments and field studies is being examined to develop a better understanding of the aggregation and subsequent transport of colloidal particles in the runoff stream to their fate in streams and estuaries.