Causes of Runoff

Adverse Effects of Urban Runoff

Contaminants in the water that “runs off” these urban areas pose a risk to human health and to aquatic animals. Many people, either because of lack of knowledge, or care, dispose of many of the harmful hazardous wastes improperly by dumping them in storm drains. Once in the drainage system, these harmful chemicals and solvents will degrade the quality of the body of water that it discharges into. As a result, ill health to both humans and aquatic species could result.

Another component frequently found in urban runoff is fertilizers. Many of those who live in the suburban areas want to have manicured lawns that require the use of fertilizer. Fertilizer contains nitrogen and phosphorus. Both of these chemicals will cause the accelerated growth of aquatic plants and algae which use all the available oxygen in the water, and results in fish kills. The loss of the fishes degrades the quality and enjoyment of the river or stream.

Herbicides and pesticides both contain chemicals that are made to kill life. Their introduction into the body of water will cause a large risk to human health and the environment.

The plastics and other trash that people frequently litter the streets with, will eventually end up in the storm drainage system. Plastics take hundreds of years to biodegrade, and even may be mistaken for food. Their presence creates a threat to the ecology of the stream or river.

Nearly all contaminants in urban runoff can pose a threat to human health and environmental health. These risks create a demand for urban runoff to be cleaned, or people should take more responsibility when disposing of waste from the household. In addition to public health and environmental health, it becomes hard to define who is liable for the damages caused by runoff. There is no existing legislation that addresses the problems that urban runoff creates. The system throws everything that can float or be transported by rainwater into a river or stream that may not have the assimilative capacity to handle the pollution. It is impossible to pinpoint a single party liable for the problem.

A partial remedy of the urban runoff problem would require that people collectively be more sensible and responsible, and make an effort to keep the storm drainage system free from contaminants. Unfortunately, it is often hard to get people to change their ways.

To sum up, urban runoff is a threat to human and environmental health. It harbors potentially dangerous contaminants that cause a reduction in the overall quality of the body of water it discharges into. In addition, the solution is not found by conventional methods based on property rights, but rather requires collective action of those living in the cities and suburbs to remedy the situation.