Nonpoint source pollution (NPS)
When it comes to defining what nonpoint source pollution means, the easiest way to do it, is to define what nonpoint source pollution is not. Unlike point source pollution which comes from a specific and localize point of origin ( a well, channel or ditch, a factory, a boat), in this classification , pollution comes from various and diffuse sources not just one. Think of it this way: a factory's pipe is where all the wastes come out of, hopefully previously treated, and go into the water bodies. Then you can identify the pipe as the point source, the pipe would be ground zero, where contaminating wastes meet the water, polluting it.
In the case of nonpoint source pollution, contaminants are not directly pour into rivers and oceans from a point source, but as runoff from urban and agricultural areas. Storms wash and flow over different surfaces like buildings, side walks, streets, farms, barns, and lawns, it filtrates, mixing and taking with it chemicals and pollutants, this is known as runoff. It is runoff what makes NPS (acronym of nonpoint source pollution) the leading cause of pollution in the water in America, and agricultural runoff is the main cause. When rain falls over urban areas washing buildings, parking lots, lawns, roads and highways creating runoff is called urban runoff, agricultural runoff happens when the rain drains agricultural areas such as feedlots and plantations.
Although agricultural runoff is the leading cause of nonpoint source pollution, is important to mention other types such as sedimentation, the excess of nutrients, and chemicals. Sedimentation is basically loose soil that causes the water to be darker and turbid, this makes it harder for the sun rays to penetrate all the way to the deep waters, inhibiting growth of aquatic life and the drinking of the water. Although nutrients are good for humans, when dump in excessive amounts into rivers and lakes it accumulates. Pollutant nutrients such as phosphorus and Nitrogen, that are the main ingredients of fertilizer and pesticides, and they come from landfills, livestock operations, feedlots, farms and plantations. In large amounts nutrients cause water plants to reproduce profusely, later when they die, since the bacteria that decomposes it requires big quantities of air, the water in the zone suffers form hypoxia (lack of oxygen). Chemicals such as zinc, mercury lead, and PCBs don't breakdown easily and the come from various sources such as vehicles, mining operations, urban runoff, DDTs, and industrial practices.
Because we can't point our finger at the exact source of pollution, it doesn't mean there isn't one. What it really means is that the leading cause of water pollution is not a factory doing a wrong waste disposal, is us as country as a big community. Your daily practices, (specially if they are not eco friendly) pollute the earth, but because is hard to determine exactly how much each of us pollute is easier to think of it and analyze it as a whole. This means the WE need to do something. If each one of us educates our friends and families about the topics such as nonpoint source water pollution and encourage them to play an active roll in protecting and cleaning our rivers our world might just be a better place.