How does stormwater differ from sanitary wastewater?

Stormwater is defined as runoff that occurs when precipitation, such as rain or snowmelt, flows over surfaces like streets, parking lots, and roofs. This runoff may pick up debris, chemicals, oils, and other pollutants from these surfaces before entering storm drains. Sanitary wastewater, on the other hand, originates from human activity, specifically the usage of water for cooking, cleaning, bathing, and other household or industrial functions. It's characterized by its content, which includes organic matter, nutrients, and pathogens, all of which typically require treatment before discharge into the environment.

This distinction is crucial because it highlights the fundamental differences in the sources and characteristics of the two types of water. Stormwater doesn’t go through conventional treatment processes before being discharged into waterways, unlike sanitary wastewater, which must undergo thorough treatment at wastewater treatment plants to remove contaminants and protect public health and the environment.