Nonpoint source pollution includes agricultural chemicals, animal waste and urban runoff. Unlike pollution that traces to a single sources such as a factory, nonpoint source pollution comes from many different locations. Runoff water from storms carries the pollutants to streams, lakes and rivers.
According to the EPA, nonpoint source pollution was the leading cause of problems with water quality in 2010. Each individual plays a role in nonpoint source pollution, often without realizing it. Farmers who apply too much fertilizer, too much herbicide or too many other chemicals to their crops increase pollution in nearby streams. Livestock waste increases chemical and bacterial pollution.
In urban areas, many types of nonpoint source pollution affect surface waters. Improper use of lawn chemicals also plays a role in the problem. Oil or fuel leaks from vehicles wash into streams. New construction increases the soil and sediment in streams. Pet owners who fail to clean up pet waste allow it to diminish water quality.
Nonpoint source pollution adds sediment, nutrients, toxins, chemicals and pathogens to the water it pollutes. It can transform a living stream into one that is no longer able to support life. Controlling nonpoint source pollution requires a unified effort on the part of all who contribute to it.