Religious and traditional uses of geothermal springs have been an ancient practice across the world even before modern civilization. For instance, the American Indians used the geothermal springs for traditional rituals and as a neutral ground where different tribes could hunt, trade and bath and where warriors could travel and relax (Hoole, 2001). The Greeks usually attribute their religion to cleanliness. Therefore, they built their temples close to the geothermal springs so that the water reticulation system could bring water to the holy place (Virk et al., 1998). Africans were not exempted from these beliefs; geothermal springs found at the Gumara River in Ethiopia were discovered by Ethiopian saints; Qergos and Takla Haymanot. It was believed that saint Qergos, while flying in the sky, was attacked by eagles and his bones fell to the ground causing warm and healing water to rush out where they were dropped (Pankrust, 1990). Some of the sites have been declared heritage sites and are presently visited by both local and international tourists (Pankrust, 1990; Nguyen, 2007).
2.4.2 Medicinal benefits
Medicinal benefits and religious purposes of geothermal springs are interrelated and can be traced back to 2,500 years ago (La Moreaux and Tanner, 2001). Geothermal springs were believed to be a special kind of groundwater owing to its higher mineralization as well as trace elements, dissolved gases, radioactivity or temperature (Wang and Xie, 2003). Different minerals and gases within the geothermal waters have proven to have different curative abilities. The use of carbolic water is thought to have significant medical importance for circulatory and heart disorders (Skapare et al., 2003). Sulphated water may heal hepatic insufficiency and problems with the accumulation of organic waste (Skapare et al., 2003). Bicarbonated water may relieve
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gastro-intestinal illness, hepatic insufficiency and gout (Skapare et al., 2003). Sodium chlorinated water may cure chronic infection of the mucous membrane (Lund, 2000; Skapare et al., 2003).
Ancient Greeks and Roman prescribed drinking and bathing in geothermal springs for its therapeutic effects especially for ailments such as jaundice and rheumatism (Hoole, 2001; Spicer and Nepgen, 2005). Chinese people used the Huang hot spring on the Shahe River for treatment of various ailments (La Moreaux and Tanner, 2001; Spicer and Nepgen, 2005). The Ethiopians used geothermal springs for the treatment of various diseases, such as skin diseases, leprosy and other contagious diseases (Pankurst, 1990). The ancient Egyptians are believed to have used geothermal baths for therapeutic purposes since 2000 BC. Many of these springs became known as sacred sites, and later evolved as healing centres (Spicer and Nepgen, 2005).
2.4.3 Agricultural benefits
Thermal springs have been used for irrigation purposes from time immemorial. Chinese people have used geothermal springs since the time of the Jin Dynasty (AD 265-420) (La Moreaux and Tanner, 2001). During this period, the Cunzhou City geothermal spring in the Hunan province was used to irrigate rice paddies so that they could grow rice even during the winter season (La Moreaux and Tanner, 2001).
European Commission (1999) reported that 25% of the direct heat produced by geothermal springs is used for agricultural purposes, which can be subdivided into the following activities:
Agricultural crop drying
Aquaculture
Mushroom farming
Heating greenhouses and irrigation
The agricultural uses of the geothermal spring depend on the surface temperature of the spring which have been summarized in Table 2.1 below.
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Table 2.1: Temperatures required for various agricultural activities
Temperature in °C Agricultural uses
20 – 25 Soil heating
35 – 95 Heating greenhouses
35 – 95 Food processing
20 – 40 Aquaculture
35 – 50 Biogas processing
45 – 65 Mushroom cultivation
65 – 95 Drying fruits and vegetables
50 – 70 Pasteurisation
60 – 85 Beet sugar extraction
70 – 100 Blanching and cooking
110 – 125 Sugar pulp drying
Source: Popovski and Vasilevska, 2003
Geothermal resources can be classified as low temperature (less than 90°C), moderate temperature (90°C -150°C) and high temperature (greater than 150°C). South African geothermal springs can thus be classified as low temperature geothermal resources and can be used for activities that require temperatures below 70oC (European Commission (EC), 1999; Geo-Heat Centre, 2005) (as indicated in Table 2.1). There is real potential for some of these geothermal resources to be used to dry locally produced fruits and vegetables, mushrooms and flowers.
Siloam and Tshipise springs are located in rural areas and utilising these resources would benefit the rural communities and improve the socio-economic status of the rural population.
2.4.4 Tourism and recreation benefits
Tourism is currently responsible for the development of many geothermal springs into spas or resorts, and many spas are changing their focus to recapture the essence of a true spa’s contribution to health and well-being. Currently about 15 million Europeans immerse themselves daily in geothermal spring waters (Hoole, 2001; Spicer and Nepgen, 2005). Forty-eight countries were using geothermal springs as resorts in the year 2000 (Lund and Freeston, 2001). This does not include data on countries such as South Africa, Malaysia, Ethiopia, Mozambique and Zambia since these countries did not submit data to the Geothermal World Conference of 2000, although
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it is a known fact they do have geothermal springs and spas for recreational use (Lund and Freeston, 2001).
Tshibalo (2011), reported that 31 out of known South African geothermal springs are used for recreation and tourism purposes. Recreational and tourism facilities and activities in South African geothermal spring resorts include the following facilities and activities: exercise areas, rest areas, restaurants, ladies’ bars, shops, solariums, camping facilities, conference facilities, cocktail lounges, picnic sites, golf courses, tennis and squash courts, volleyball, snooker and pool, bowls, heated and cold swimming pools, hot mineral pools, jacuzzis, paddle boats, caravan and camping, game drives, birdwatching, and horse riding (Tshibalo, 2011).