Factors Threatening The Environment: Groundwater Depletion and Contamination

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Water that collects beneath the ground is called groundwater. Worldwide, groundwater is 40 times more abundant than fresh water in streams and lakes. Although groundwater is a renewable resource, reserves replenish relatively slowly. Agricultural practices depending on this source of water need to change within a generation in order to save this groundwater source.

In addition to groundwater depletion, scientists worry about groundwater contamination, which arises from leaking underground storage tanks, poorly designed industrial waste ponds, and seepage from the deep-well injection of hazardous wastes into underground geologic formations. By some estimates, on average, 25 percent of usable groundwater is contaminated, and in some areas as much as 75 percent is contaminated.

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