Bonneville Seabase

Bonneville Seabase near Grantsville, Tooele County, Utah, is one of the most extraordinary and counterintuitive diving experiences available in the American interior—a landlocked ocean dive in the middle of the Great Basin desert, where natural brine springs have been developed into a series of pools supporting actual ocean fish and invertebrates more than 500 miles from the nearest saltwater ocean. Located less than an hour west of Salt Lake City in the shadow of the Oquirrh Mountains, Bonneville Seabase has developed a worldwide reputation among freshwater diving communities as one of the most unexpected and memorable dive destinations in North America. The site's existence rests on the geological legacy of Lake Bonneville—the great Pleistocene lake that covered much of northwestern Utah during the Ice Age, leaving behind the Bonneville Salt Flats and the saline soils that persist across the Great Basin. Natural springs in the area emerge with salinity levels approaching that of ocean water, fed by water filtered through the salt-rich deposits of the ancient lakebed. The operators of Bonneville Seabase recognized the potential of these natural saline springs and developed a facility that imports and maintains actual marine fish and invertebrates in the spring pools—creating what amounts to a working aquarium environment accessible to scuba divers. The marine life at Bonneville Seabase includes species that no other Utah water body can host: ocean fish imported and maintained in the naturally saline spring pools, creating encounters that should be impossible in landlocked Utah but are perfectly real. Divers who descend into Bonneville's pools encounter ocean fish in the middle of the Utah desert—a cognitive dissonance that makes the experience genuinely surreal for anyone who has not encountered the concept before. The fact that the fish are in a managed facility rather than a natural ocean environment does not diminish the strangeness of seeing coral fish in desert country that the Great Salt Lake defines. Water clarity at Bonneville Seabase is typically excellent, as the spring water's source in ancient lakebeds provides water relatively free of the agricultural nutrients that cloud conventional lake and reservoir diving. The visibility that the spring pools provide gives divers a clear view of the marine life that inhabits them and the spring environment that sustains it. The warm water temperature—maintained at levels suitable for the tropical and subtropical fish species that the facility imports—contrasts with the cold freshwater springs typical of Utah's other dive sites. For beginners making their first saltwater-equivalent dive in Utah's landlocked environment, Bonneville Seabase provides an accessible introduction to the sensation of diving with ocean fish in the protected, calm environment of a managed spring pool. For more experienced divers visiting from elsewhere, the site's improbable existence—a saltwater dive in Utah's desert, ocean fish in the shadow of the Bonneville Salt Flats—makes it a worthy detour on any American interior diving itinerary, memorable precisely because it should not exist but does.