The Environmental Impact of Urban Sprawl

Urban sprawl is detrimental to the environment. Our country is facing an environmental crisis, losing green space, farmland, and important ecosystems, all at the hand of urban sprawl. As urban areas grow, the environmental problems grow exponentially. Here are some of the environmental problems caused by urban sprawl.

Decrease in Water Quality
Paved surfaces create runoff during rainstorms. This runoff picks up oil, chemicals, and gravel from the pavement and grass. These chemicals would usually be filtered out of the water through the ground, however, due to the increase in concrete, now run off into streams. Fertilizers from yards run off into streams causing algae blooms. The algae blooms decrease the oxygen in the water, killing the fish. The water supply for the towns becomes contaminated.

Decrease in Air Quality
Urban sprawl causes a significant decrease in air quality. People spend much more time in cars commuting to work and running errands. Commuting to work use to take people 10-15 minutes in the car. Today, people are spending 30 minutes or more commuting to work due to urban sprawl. The extra exhaust decreases the air quality.

Less Groundwater
More paved surface means that there is less infiltration for groundwater. Areas that depend on groundwater as a source of public water supply are facing a water crisis as the aquifer becomes depleted. In addition, these areas are facing a problem with land subsidence. The increase demand on the groundwater due to urban sprawl has created a void in the aquifer. The land compresses, causing flooding problems, cracking of foundations, etc. San Jose has suffered more than 13 feet of land subsidence due to this problem.

Loss of Farmland
Between 1992 and 1997 13.7 million acres of farmland were converted to housing developments and highways.

Loss of Wetlands
Wetlands surrounding streams help prevent flooding. In addition, wetlands slow down runoff entering a stream. Wetlands absorb chemicals in runoff. Without wetlands to act as buffer, the water supply becomes contaminated and more areas flood.