Point source pollutants empty into the river from a single pipeline or location. An example is the discharge pipe from a large facility that treats wastewater from our homes and businesses.
Because point source pollutants enter the water at a specific location, they are easier to control than dispersed-source pollutants. The amount of the pollutant that goes into the river can be monitored by local and federal authorities, like the EPA (Environmental Protection Agency).
General types of water pollutants include disease-causing bacteria, plant nutrients and fertilizers, chemicals, oil, radioactive substances, heat and sediment (dirt, clay and rocks).
Sewage from wastewater treatment plants is the primary source of disease-causing bacteria, plant nutrients and other waste in rivers.
Rain runoff pushes non-point source (dispersed-source) pollutants into the river. Along with loose dirt or clay, rainwater also carries pesticides and fertilizers into rivers and streams. Various non-point source pollutants can originate from agriculture, construction, and deforestation.