Storm water runoff picks up pollutants and debris as it flows across rooftops and lawns, streets, and parking lots. During periods of rainfall, pollutants are picked up and washed directly into our streams, rivers, and lakes. Some of these pollutants include oil and grease, harmful bacteria, fertilizers, toxic chemicals, and other contaminants which are harmful to both people and aquatic life. A common misconception is that water running off streets and into a storm drain goes to a wastewater treatment plant. It does not. In fact, storm water usually receives no treatment.