Here is a list of common stormwater pollutants and their potential sources:
- Sediment – Usually one of the largest pollutants produced in cities and towns, sediment is especially found in areas where there is a lot of construction. Many other pollutants often attach to, and are carried by, sediment particles.
- Nutrients – Phosphorus and nitrogen are nutrients often associated with stormwater runoff. Nutrients can come from landscaping (commercial and residential), leaks from sanitary sewers and septic systems, and animal waste.
- Organic Matter — Sources of organic matter include leaves and grass clippings, animal/pet waste, garbage and litter.
- Bacteria – High bacterial levels may be found in stormwater runoff from leaking sanitary systems, garbage, pet waste, etc.
- Oil and Grease – Traffic and other activities on roadways produce oil, grease, and lubricating agents that are easily transported by stormwater.
- Toxic Substances – Metals, pesticides, herbicides and hydrocarbons such as gasoline and methane can get into and be transported by stormwater runoff.
- Heavy Metals – Heavy metals such as copper, lead, zinc, arsenic, chromium and cadmium are often found in stormwater runoff polluted by batteries, paints, motor oil and other items.
- Temperature – stormwater runoff becomes warmer as it flows over hard surfaces. Water stored in shallow, unshaded ponds also becomes warmer. Taking away natural plants and trees can open up water bodies to the direct sun. As water warms, it may be harmful or even deadly to some fish and other life in the Rio Grande.