Direct Use of Geothermal Water at the Solage Calistoga Resort, Napa County, California

Abstract

Direct utilization of low to moderate geothermal resources for bathing, balneology or space heating started growing since the end of the 20th century in California and the U.S. Calistoga, in California, became one of the major towns for spas and resorts since the mid 1980s when several new resorts opened. Most waters used come from shallow wells (~200 feet) with temperatures from 170°F to 200°F, but recently, higher temperature were measured in a deeper reservoir, increasing the estimated size and longevity of the Calistoga geothermal reservoir. The Solage Calistoga Resort, opened in 2007 currently uses fluid from one of the two shallow wells that were drilled on the property in 2006. Fluids at temperatures of 204-212 °F heat swimming pools and other spas as well as heating the facility.