Jáchal River
Encyclopedia
The Jáchal River is a river in the province
of San Juan
, Argentina
. It is part of the Desaguadero River
basin, and one of the most important permanent watercourses in the province, with an average flow of 9 m³/s. It is born from the confluence of the Río de la Palca and the Blanco River, in the northwest of San Juan.
From its origin, the Jáchal flows south for 75 km, up to a ravine
in the pre-Andean
range, in a place called Cuesta del Viento. There, it turns eastward towards the city of San José de Jáchal
, flowing for 40 km along a steep gorge. Upon reaching Jáchal, the river turns south again for 40 km, and then northeast-southeast, passing by the towns of Tucunuco and Mogna. It then flows 100 km and empties into the upper Desaguadero River (here known as Bermejo).
The Jáchal River is fed primarily by snow thaw, rainfall being only a minor contribution in this semi-arid region. Its drainage basin
covers an area of 34,232 km², or around 23,000 km² if considered up to Cuesta del Viento.
The river is dam
med in two points:
and boron
content. The latter has been found in concentrations of 2.8 parts per million (0.7 ppm are considered the upper limit for sensitive crops such as the grapevine
).
In the early 2000s, Barrick Gold Corporation, a Canadian
enterprise, started a gold extraction
project in the San Juan Andean ranges. Residents of San Juan protested against the project, claiming that the cyanide process
will pollute the upper courses of the Jáchal and San Juan
rivers. In an interview in February 2006, the governor of San Juan, José Luis Gioja
, denied the possibility of such damage.
Provinces of Argentina
Argentina is subdivided into twenty-three provinces and one autonomous city...
of San Juan
San Juan Province (Argentina)
San Juan is a province of Argentina, located in the western part of the country. Neighbouring provinces are, moving clockwise from the north, La Rioja, San Luis and Mendoza. It borders with Chile at the west....
, Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
. It is part of the Desaguadero River
Desaguadero River
The Desaguadero River is the general name of a river in western Argentina that receives a number of different names on its path of 1,515 kilometres, with its most important section named Desaguadero proper.-Spring:...
basin, and one of the most important permanent watercourses in the province, with an average flow of 9 m³/s. It is born from the confluence of the Río de la Palca and the Blanco River, in the northwest of San Juan.
From its origin, the Jáchal flows south for 75 km, up to a ravine
Ravine
A ravine is a landform narrower than a canyon and is often the product of streamcutting erosion. Ravines are typically classified as larger in scale than gullies, although smaller than valleys. A ravine is generally a fluvial slope landform of relatively steep sides, on the order of twenty to...
in the pre-Andean
Andes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...
range, in a place called Cuesta del Viento. There, it turns eastward towards the city of San José de Jáchal
San José de Jáchal
San José de Jáchal is a city in the northeast of the province of San Juan, Argentina, located on National Route 40, south of the Jáchal River. It has 21,018 inhabitants per the , and is the head town of the Jáchal Department....
, flowing for 40 km along a steep gorge. Upon reaching Jáchal, the river turns south again for 40 km, and then northeast-southeast, passing by the towns of Tucunuco and Mogna. It then flows 100 km and empties into the upper Desaguadero River (here known as Bermejo).
The Jáchal River is fed primarily by snow thaw, rainfall being only a minor contribution in this semi-arid region. Its drainage basin
Drainage basin
A drainage basin is an extent or an area of land where surface water from rain and melting snow or ice converges to a single point, usually the exit of the basin, where the waters join another waterbody, such as a river, lake, reservoir, estuary, wetland, sea, or ocean...
covers an area of 34,232 km², or around 23,000 km² if considered up to Cuesta del Viento.
The river is dam
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
med in two points:
- The Cuesta del Viento Dam, 40 km from Jáchal, has a maximum volume of 136 million m³. It is used to regulate and direct the flow for irrigationIrrigationIrrigation may be defined as the science of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and revegetation of disturbed soils in dry areas and during periods of inadequate rainfall...
, and long-delayed works are in progress to finish a hydroelectricHydroelectricityHydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy...
power stationPower stationA power station is an industrial facility for the generation of electric energy....
. - The Salto de la Loma hydroelectric plant, 4 km northwest of Jáchal, employs a 40 m high fall and has an installed power of about 1,200 kWWattThe watt is a derived unit of power in the International System of Units , named after the Scottish engineer James Watt . The unit, defined as one joule per second, measures the rate of energy conversion.-Definition:...
.
Environmental issues
The Jáchal is the most important natural source of water for domestic, agricultural and industrial use in its valley, but the quality of its waters is not considered good in normal conditions, due to a high mineralization, especially saltsSalinity
Salinity is the saltiness or dissolved salt content of a body of water. It is a general term used to describe the levels of different salts such as sodium chloride, magnesium and calcium sulfates, and bicarbonates...
and boron
Boron
Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...
content. The latter has been found in concentrations of 2.8 parts per million (0.7 ppm are considered the upper limit for sensitive crops such as the grapevine
Grape
A grape is a non-climacteric fruit, specifically a berry, that grows on the perennial and deciduous woody vines of the genus Vitis. Grapes can be eaten raw or they can be used for making jam, juice, jelly, vinegar, wine, grape seed extracts, raisins, molasses and grape seed oil. Grapes are also...
).
In the early 2000s, Barrick Gold Corporation, a Canadian
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
enterprise, started a gold extraction
Gold extraction
Gold extraction or recovery from its ores may require a combination of comminution, mineral processing, hydrometallurgical, and pyrometallurgical processes to be performed on the ore....
project in the San Juan Andean ranges. Residents of San Juan protested against the project, claiming that the cyanide process
Gold cyanidation
Gold cyanidation is a metallurgical technique for extracting gold from low-grade ore by converting the gold to a water soluble coordination complex. It is the most commonly used process for gold extraction...
will pollute the upper courses of the Jáchal and San Juan
San Juan River (Argentina)
The San Juan River is, together with the Jáchal, the most important river of the Argentine province of San Juan. Both join the Desaguadero/Colorado system that end at the Atlantic Ocean....
rivers. In an interview in February 2006, the governor of San Juan, José Luis Gioja
José Luis Gioja
José Luis Gioja is an Argentine Justicialist Party politician, current governor of San Juan Province and former President of the Argentine Senate....
, denied the possibility of such damage.