What Is Storm Water Runoff?

Storm water runoff is a major cause of water pollution in both urban and suburban areas. When it rains, the rain that falls on streets, roofs, and other impervious surfaces such as sidewalks where the water cannot soak in the ground. Instead, it runs off into storm drains, and carries bacteria, trash, heavy metals, and other pollutants with it. These storm drains can lead into water bodies like streams, bays, and even groundwater, which provides us with water to drink.

Pollutants such as fertilizers, pesticides, bacteria from pet waste, eroded soil, road salt, and litter can contaminate water bodies by being carried into storm drains from storm water runoff. Excess phosphorous and nitrogen from fertilizers can impact the local environment when carried into water bodies by storm water runoff and cause algal blooms. These algal blooms, sometimes called a “brown tide” or a “red tide,” can kill massive amounts of marine wildlife and even close Long Island beaches in the summer time. Rain gardens can trap these pollutants and even break them down over time.

Storm Water

Storm water that flows off of impervious surfaces can carry pollutants into storm drains.

Algae Blooms

When chemicals like fertilizers are carried off of the land and into local water bodies, they can cause massive algae blooms.

Dangers To Wildlife

Photo: NY Times

Algae blooms and other pollutants threaten local marine animals. See NY Times article: Long Island Sees a Crisis as It Floats to the Surface