Point pollution is pollution that is caused by a single, identifiable source. This contrasts with non-point sources of pollution, which are not discrete entities. A broken sewage pipe spilling untreated water into a river is an example of point source pollution. Conversely, the combined oils, pesticides and other chemicals carried by runoff in an urban area do not have a single source and are considered non-point sources of pollution.
Common point sources of water pollution include factories and animal farms. Many factories release wastewater into local rivers and lakes. Some factories treat the water before discharging it, but others do not. Animal farms create point source pollution as the runoff water that travels over the farm collects pollutants. The water then carries these pollutants down to a small portion of a water body, creating an easily identifiable source for the pollution.
The term point source pollution may be applied to any type of pollution that has a single source. While pollution is most commonly associated with water and air, other types of pollution exist. For example, some people consider street lamps to be a form of light pollution. In this case, a single street lamp represents a point source of pollution, while the combined lights of an urban area represent non-point sources of pollution.