eruptions for tourist displays, and channels and dams were also built around thermal features to manipulate geyser activity (Cody and Lumb 1992, Rinehart 1980). Other geysers were lost as a result of natural activity. Waimangu Geyser, the larg- est geyser ever documented in terms of height and volume, formed in 1900 and became extinct in 1904 as a result of land- slide materials blocking its vent (Hunt et al. 1994).
El Tatio, Chile. El Tatio has so far been spared large-scale geothermal development, in part because of its remote loca- tion in the Chilean Andes. The Chilean government drilled six exploratory wells and seven production wells between 1969 and 1974, but the project was soon abandoned and no stud- ies on impacts to thermal features were undertaken. El Tatio has since become a tourist destination, albeit not a developed one. There are no designated roads or walkways, nor is there a management system in place. Human impacts observed by Glennon and Pfaff (2003) were relatively minor and included objects thrown into springs and geysers and tire marks on ther- mal features.
Iceland. Being a volcanic island, Iceland lacks fossil fuel energy reserves and depends almost entirely on geother- mal energy and hydropower. The primary use of geothermal resources is for space heating; 87% of Iceland’s 280,000 resi- dents live in homes with geothermal heat (Ragnarsson 2003). Prior to exploitation, approximately 60 geysers existed in scat- tered basins, mostly on the western side of the island (Barth 1950). There are no specific studies, at least in the English language, that document the disappearance of geysers in Ice- land. There is evidence that geysers were soaped and fitted with pipes to induce eruptions (Barth 1950, Nielsen 1937), but it is uncertain if these actions had any long-term effects on geyser activity. Bryan (1995) indicates that most of the ther- mal features in the Reykir geyser basin have been destroyed by geothermal drilling, and that many of the individual features scattered across the island are gone as well. Iceland now has fewer than 30 active geysers.
Valley of Geysers, Russia. Reports by Russian scientists indicated that there were more than 20 geysers present in the Valley of the Geysers on the Kamchatkan Peninsula when they first explored it in 1941. Bryan observed at least 200 geysers during field research in 1991. The area has not been com- mercially developed for tourism or energy development and is protected as part of the Kronotsky Nature Preserve, which encompasses an area approximately equal in size to Yellow- stone. Access in the past was difficult, expensive, and usually undertaken only by ecotourism-related travel companies. As such, the Valley of Geysers thermal features are not believed to have been altered by human activity (Bryan 1995). How- ever, in June 2007, a massive landslide buried some of the features under as much as 60 meters of debris and dammed the nearby Geysernaya River. The flooding from the river has turned much of the valley into a lake, silencing many of the remaining geysers. The ramifications of this natural disruption
have not yet been fully evaluated.
United States. In the U.S., the shift from dry steam to hydrothermal reservoirs for geothermal energy production in the 1950s resulted in increased exploration of hydrothermal systems. By 1965, the drilling of exploratory wells had caused the loss of all natural geyser activity at Beowawe and Steamboat Springs in Nevada, the two largest geyser basins in the U.S. outside of Yellowstone (White 1967, 1992). The Geyser Bight Geothermal Area on Umnak Island in the Aleutian Islands is part of one of the hottest and most extensive areas of thermal springs in Alaska (Motyka, et al. 1993) and is the only geyser location in the United States other than Yellowstone that has not been altered by geothermal resource development. Geyser Bight has been spared mainstream tourism and geothermal development due to its remote location. However, research funded by the U.S. Department of Energy concluded that the region would make an excellent site for geothermal energy development for industries wishing to site themselves in the Aleutians (Motkya et al. 1993, Nye et al. 1990). In Yellowstone a small number of geysers have stopped functioning as a result of tourism-related activities, as described below, but there is potential for greater damage if geothermal development occurs outside the park boundaries.
Yellowstone’s Geothermal Landscape
Although Native Americans were aware of Yellowstone’s geyser basins, the first Euro-American reports of the region surfaced in the late 1820s when American trappers moved into the Yellowstone region. Few Americans believed trapper and mountain man Jim Bridger’s tales of hot water and steam shooting up out of the ground, but his stories inspired the Folsom-Cook expedition to investigate and finally confirm his stories by 1869. The following year, a party led by Henry
An eruption of Yellowstone’s Beehive Geyser.
17(1) • 2009