Lisa S. Alter
Runoff is the major source of nonpoint pollution entering Long Island Sound. Rain washes contaminants, litter and soil into streams, rivers and bays. As water flows over or underground, it picks up pollutants. Farming can add nutrients and pesticides from animal wastes and fertilizers to the runoff. (Beristain, 1989)
In urban areas, where there is a lot of developed land, materials such as asphalt and concrete, along with buildings prevent rain from soaking into the ground. Here rain collects in storm drains, then goes directly into rivers and streams on its way to the Sound. This increase in runoff prevents water from being naturally filtered by soil. (Beristain, 1989)
Cars, highways and parking lots add oil, grease, and lead to runoff into the Sound. One-fourth of a teaspoon of oil will form a 200 square foot oil film on the Sound’s surface. Litter washes from the streets into storm drains, on its way to the Sound. (DEP, 1996) Storm drains are part of nonpoint source pollution. A misconception that many people have is that storm drains lead to a sewer treatment plant, but this is not the case. After water enters a storm drain it is usually transported directly to the nearest lake, river, stream or wetland. (DEP, 1996)
Rivers are also considered nonpoint pollution sources because their water condition varies depending on the activities within the watershed. (Beristain, 1989)