by Craig Robinson, a student at the University of Pittsburgh
Stormwater Runoff is the number one threat to water quality according to the United States Environmental Protection Agency (EPA).
Stormwater Runoff is rainfall that lands on an impervious surface, such as concrete or asphalt; this rainfall eventually makes its way through the sewage system into a nearby body of water.
Stormwater Runoff endangers public health and the environment because it can carry contaminants picked up from the ground – including waste, oils, fertilizer, pesticides, and viruses – which also flow into oceans, streams, and lakes.
Prior to the development of cities, rain would fall on permeable surfaces, such as forests.
A permeable surface can naturally absorb rainwater into the ground. This filters out pollutants and promotes plant growth.
Permeable surfaces have been paved over by concrete and asphalt, which are incapable of absorbing rainwater. In Hoboken, New Jersey, 57% of impervious areas are found in rooftops: a total of 45% of the city’s area.