In the Precambrian Shield there are no continuous aquifers and ground water is only found in the fractured and weathered zones of Precambrian rock. These various aquifers are located primarily in gneiss and granite. The Precambrian shield only makes up a small portion of eastern Bolivia. Aquifers in this province are generally shallow at depth less than 90 meters and due to this many of the aquifers are biologically contaminated near populated areas (Roebuck et al. 2004). Majority of the ground water that is used in this area come from alluvial aquifers located near the Rio Paragua (Roebuck et al. 2004). Within the Gran Chaco and Beni Plains there are several groundwater sources in Quaternary age alluvial aquifers and sedimentary and igneous
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There are four major basin found on the plateau that were formed due to the mountainous spurs that jut out along the Andes Mountains. There has not been flooding due to Lake Titicaca in over 30 years due to better regulations and weather but if flooding were to occur the village houses on the shore of Lupalaya would be overtaken by water (Roebuck et al. 2004). The same problem occurs if there is a heavy enough rain as there will be runoff from the surrounding hills which will drag water and sediment into homes at the base of the hills. These surrounding hills also help replenish the underground aquifers from the runoff of rainwater they …show more content…
The reason the lake has such a great rate of evaporation compared to other large lakes is due to the facts; the high elevation of the lake therefore lower air pressure, and lack of air humidity that creates a vapor pressure deficit. Annual evaporation for the lake is 90% of the lake’s water loss and water balance of the lake greatly depends on evaporation flux from year to year, the other 10% loss is to the Rio Desaguadero (Delclaux et al. 2007). The lake drains a 49000 km^2 watershed with its main outlet being Rio Desaguadero. The evaporation rate has been measured in very wide range from 1350 mm to 1900 mm (Delclaux et al. 2007). With these values the lake water level can vary with a rise and fall from .20 to .40 m. Due to this wide range of evaporation the source of freshwater use from the lake with the regulations in place affects the surrounding villages greatly in their water use. Water penetration into surrounding aquifers is not well documented but with the limited information it has been estimated that the percentage of infiltration into the aquifers are 10% (Delclaux et al. 2007). With this low value of infiltration it means that over pumping aquifers is a major problem even with Lake Titicaca in close proximity, as is evident in La
There are four major basin found on the plateau that were formed due to the mountainous spurs that jut out along the Andes Mountains. There has not been flooding due to Lake Titicaca in over 30 years due to better regulations and weather but if flooding were to occur the village houses on the shore of Lupalaya would be overtaken by water (Roebuck et al. 2004). The same problem occurs if there is a heavy enough rain as there will be runoff from the surrounding hills which will drag water and sediment into homes at the base of the hills. These surrounding hills also help replenish the underground aquifers from the runoff of rainwater they …show more content…
The reason the lake has such a great rate of evaporation compared to other large lakes is due to the facts; the high elevation of the lake therefore lower air pressure, and lack of air humidity that creates a vapor pressure deficit. Annual evaporation for the lake is 90% of the lake’s water loss and water balance of the lake greatly depends on evaporation flux from year to year, the other 10% loss is to the Rio Desaguadero (Delclaux et al. 2007). The lake drains a 49000 km^2 watershed with its main outlet being Rio Desaguadero. The evaporation rate has been measured in very wide range from 1350 mm to 1900 mm (Delclaux et al. 2007). With these values the lake water level can vary with a rise and fall from .20 to .40 m. Due to this wide range of evaporation the source of freshwater use from the lake with the regulations in place affects the surrounding villages greatly in their water use. Water penetration into surrounding aquifers is not well documented but with the limited information it has been estimated that the percentage of infiltration into the aquifers are 10% (Delclaux et al. 2007). With this low value of infiltration it means that over pumping aquifers is a major problem even with Lake Titicaca in close proximity, as is evident in La