• Explore and Discover One of the Last Frontiers in the World ...

    Jewel Cave

    National Monument South Dakota

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  • Caution - Roadwork on Highway 16 - Expect Delays

    Construction projects both along highway 16 and the Jewel Cave parking lot are planned during the summer. The visitor center is open daily with tours scheduled throughout the day. Come early, pm tours are usually full. No reservations for cave tours.

  • Highway 16 construction near Jewel Cave entrance

    Construction of Highway 16 through Jewel Cave National Monument is progressing on schedule. Motorists should use caution while traveling through the construction zone. Visitors to Jewel Cave should plan extra travel time and come early in the day. More »

  • The parking lot at Jewel Cave takes shape

    Jewel Cave's parking lot project is on schedule for completion by September 30. The patio area outside the visitor center is planned for work in August. Signage along a service road and staff assistance will help guide visitors to the visitor center. More »

Water Quality

A physical science intern takes a water sample inside the cave

Monthly water sampling is conducted at several sites inside Jewel Cave.

NPS Photo

There are over 50 places inside Jewel Cave where water drips from the ceiling, and a few isolated places where this water has collected in pools. All of the water inside the cave comes from the surface, and all activities above the cave can have a dramatic effect on water in the cave below.

Road salts, chemicals, sewer lines, and fuel and oil from vehicles all have the potential to impact water quality inside the cave. At Jewel Cave National Monument, a monthly monitoring program checks the water quality at several drip sites in the cave. Elevated chloride levels that have been discovered at some sites most likely point to the use of salts to de-ice roads.

Due to water quality concerns, the park management is very cautious when deciding whether or not to use chemicals above the cave. Such decisions are based on the best available science, and consider such factors as soil depth and composition, geology, and hydrology. For example, chemicals cannot be used to kill noxious weeds in most areas of the park because the cave is vulnerable to infiltration of pesticides. To protect water quality, the park relies primarily on manual control of exotic plants (hand pulling and cutting).

Did You Know?

Bats on the cave ceiling/NPS file photo

Jewel Cave National Monument is home to nine bat species, including the rare Townsend’s big-eared bat. Some bats that roost outside in the summer hibernate in the cave during winter.