What is a primary characteristic of sewage in general?

Sewage is primarily characterized by its inclusion of human waste. This characteristic is significant because it directly highlights the nature of sewage as a product of human activity, which includes not only bodily waste but also various contaminants and pollutants that accompany it. The presence of human waste in sewage necessitates specific treatment processes to ensure that public health and environmental standards are met before any potential discharge or reuse.

While sewage may contain various other components, including food waste, chemicals, and water, the defining element is the human waste, which poses the greatest risk if not properly managed. Understanding this characteristic is fundamental to grasping the importance of sewage treatment systems and the implications for public sanitation and environmental protection.