While it's difficult to look underground to tell if you live in a karst area, you can check the surface for clues. If you live near sinkholes, caves, sinking streams, or large springs then you live in a karst region. Twenty percent of the land in the United States is classified as karst. Karst is found throughout the US and the look varies from region to region. Examples of karst include the huge clear springs of Florida, the large and decorated caves of New Mexico, and the sinkhole plains of Kentucky.

Water
Karst may not be a well known word, but it is a common feature across the country as one fifth of the landmass of the United States is karst and 25% of the nation’s drinking water comes from karst aquifers. Karst regions contain some of the largest and most productive aquifers that are capable of providing large supplies of water.

On the downside, surface water in karst areas flows into caves and sinkholes very quickly, receiving very little filtration. This water, and the impurities it carries - human and animal waste, pesticides, fertilizers, petroleum products, and other pollutants - often travel great distances underground, contaminating wells, springs, and aquifers.

Endangered Ecosystems
Karst areas contain some of the most fragile ecosystems on Earth. Many endangered and threatened species are endemic to a single sinkhole or cave. Pollution or disruption to one sinkhole could easily wipe out an entire species.