It might seem that the cave is isolated from the surface world, and that our activities above the cave would have little or no effect on the cave below.  However, that is not entirely true.   Wherever moisture from rainfall or snow melt is able to seep underground, a connection is made between the surface and the cave. 

Jewel Cave National Monument strives to maintain the natural quality and quantity of water entering the cave, but the infrastructure that has provided opportunities for park visitors (the parking lot, visitor center, restrooms, administrative facilities, etc.) has in some cases changed the natural hydrology.

Developed areas cause runoff, which redirects the water.  Some areas of the cave may now be wetter than they were naturally, and others may be drier.  Such changes in hydrologic patterns can have an effect on how and where speleothems (cave formations) will form. 

Forested areas above Jewel Cave typically receive less moisture than open, grassy areas. This is because trees take up much more rainwater than grasses do. When the surface of Jewel Cave was heavily forested with ponderosa pines, less moisture got into the cave. The Jasper Fire killed many of the pine trees, leaving the area open for grassy meadows. As a result, more rain water is expected to enter the cave, causing more changes.

The fire opened up the meadows to native plants such as blanketflowers, purple coneflowers, and western wheatgrass. Unfortunately, the fire-disturbed land also encouraged the growth of exotic plants such as mullein and Canada thistle.