Karst in Indiana - Contamination of Ground Water in Karst Environments

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Caves & Karst > Karst in Indiana

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Contamination of Ground Water in Karst Environments

Ground water in karst terrains is contaminated easily because the surface waters are channeled rapidly into the subsurface at sinkholes and swallowholes. These waters then flow underground without the benefit of filtration or exposure to sunlight, which might remove or kill some organic contaminants. Eventually, the ground water exits at springs. Contaminants from livestock feeder lots, agricultural pesticides, poorly managed industrial plants, leaking gasoline tanks or spills, septic fields, and sewage plants may be discharged at these springs without being adequately diluted. Wastes located in sinkholes, including dead livestock, discarded chemical containers, waste oil, and batteries also can be washed into the underground conduit and cavern systems.

Cross section diagram showing how different surface contaminants reach ground water.
Diagram concept by R.L. Powell; drafted by R.S. Taylor

Ways to protect the karst environment

Learn more about your karst environment. Talk with your educators or other providers of environmental information in your community.
Don’t dispose of trash in sinkholes.
Check the regulations in your county before installing a septic system or animal waste lagoon. Always divert any contaminated runoff away from sinkholes.
If your drinking water is from a well, be sure to have a sample of the water tested regularly for bacteria and nitrate content.
Be aware that improper use of insecticides, herbicides, and fertilizers can contaminate the ground water. Read the instructions and do not overapply.

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