Golden Haven Spa Direct-Use Geothermal Project, Calistoga, California

Golden Haven Hot Spring Spa and Resort is one of several geothermal spas in Calistoga, California in the northern Napa Valley. Low to moderate temperature (60 °F - 275°F) geothermal fluids occur in the shallow subsurface over a 5.79 mi2 area around Calistoga and have been utilized in local spas since the early 1860’s. The City of Calistoga has been trying to curtail the existing practice of spas, like Golden Haven, discharging spent geothermal fluids to the municipal sewer system because dissolved geothermal constituents can exceed regulatory limits in municipal treatment plant fluids released to the Napa River during winter months or used for irrigation during the summer. With cooperative funding from the California Energy Commission, Golden Haven drilled and completed the GHS-3 injection well at a total depth of 608 ft. to reduce the spa’s contribution of geothermal effluent to the Calistoga sanitary sewer system. The injection well location was chosen to minimize potential interference with the spa’s existing production well and any adjacent shallow (