The hot springs near the present town of Elko were a landmark along the old emigrant trail. In 1868 Governor Bigler and Col. Thomas Hanley built a two-room steam bathhouse at hot springs southwest of Elko and employed a doctor to supervise treatment of patients. Soon afterward, they constructed a ten-room building (Smith, 1957, p. 16-17). Adjoining springs were developed into Laurneister and Groepper's Humboldt Hot Springs; the hotel and bathhouse went through many ownerships and two disastrous fires before 1900. A brick building, rebuilt after the second fire, and the hot springs are now incorporated in Elko County's home for the aged (Patterson and others, 1969, p. 547-548). The hot springs have reportedly been utilized in hatching chickens (Adams and Bishop, 1884, p. 195), and attempts were made in 1921 at the nearby Catlin Oil Shale plant to distill oil from the local oil shales with the aid of hot water from the Hot Hole area (Patterson and others, 1969). Elko Heat Company, a private company, began supplying geothermal fluid for space heating and other uses to several downtown buildings in 1982 (Rafferty, 1988). The company has continued to grow; in 2005 it served 17 commercial customers and two residential customers (Bloomquist, 2005).The resource temperature is reported to be 77-81°C (Rafferty, 1999; Bloomquist, 2005). The Elko County School District, in conjunction with the Elko General Hospital, developed a district geothermal heating system in 1986. The system supplies heat to 16 public buildings, including schools, a convention center, city pools, and a community college building. In 1988 the estimated combined savings to all users was $300,000 per year (Rafferty, 1988; R. Harris, oral commun., 1994). The well for the district heating system, located in Sec. 11, T34N, R55E, has a reported temperature of about 86°C. Heat is transferred to a secondary loop via a heat exchanger, and that fluid is supplied to consumers (Bloomquist, 2004a; b; 2005).

The Elko Hot Springs area is about 2.4 km southwest of the center of Elko along a 0.8 km-long zone in the W½ Sec. 21, T34N, R55E. The springs are associated with fractures and adjacent to a north-northeast fault (figure). The springs flow from Tertiary sedimentary rocks (Eakin and others, 1951). Tufa at the edge of one pool is slightly radioactive, at 19 µR/hr (Wollenberg, 1974). The springs range in temperature from 65.5 to 88.9°C (Eakin and others, 1951 ;Waring, 1965).

Hot Hole. Hot Hole at the north end of the zone of springs, was a stop on the emigrant trail and its water was once used for an Elko city swimming pool (Bill White, personal commun.). The area is a travertine dome with a central hole about 60 m in diameter with a pool about 10 by 23 m. The dome is 120 to 150 m in diameter. The water level in the pool is at least 6 m above the level of the nearby Humboldt River. At one time a tunnel was cut through the dome to drain the pool, and water now flows eastward into the river. Mariner and others (1974) have estimated the reservoir temperature at 104°C with the silica geothermometer (Conductive). Nearly a kilometer to the south of Hot Hole at the site of the old spa area is the Elko County home for the aged.

Water wells. In addition, water wells in Elko have encountered warm to hot water and mud at two localities.In the SW¼ Sec. 15, T34N, R55E, two Western Pacific wells were warm to hot. A well in the north section of Elko, in the SE¼ Sec. 10, T34N, R55E, was abandoned because hot mud invaded the casing at 129.5 m. A 23.9°C well is also present to the east, in the SW¼ Sec. 11, T34N, R55E. These hot wells are near a possible projection of the same north-northeast-trending fault present at Elko Hot Springs. Audiomagnetotelluric and gravity data have been published for the Elko Known Geothermal Resource Area (Hoover and others, 1976; Peterson and Dansereau, 1976b).

Photos
Elko Convention Center.
Airphoto
Geothermal Greenhouses, north side of Humboldt river near Hot Hole.
L shaped lap pool in Elko.