Pactola Reservoir

The largest and deepest reservoir in the Black Hills (about 800 acres, up to 150 ft deep), 15 miles west of Rapid City, flooded over the 1950s gold-rush-era town of Pactola. Divers explore remnants of the old town site, a dynamite bunker, railroad bed and CCC-camp structure, with roughly ten recognized dive spots from 15 to 90 ft; common entries are the swim beach at Pactola Point, the dam and the trail below the visitor center. Water is clear for the region (20-25 ft visibility) with a sharp thermocline around 40 ft, and this is a high-altitude dive at roughly 4,600 ft elevation.