Lake Poopó was once a huge saline lake, nestled in a shallow depression of the Altiplano Mountains at an altitude of 3,700 meters in Bolivia. As of December 2015 the lake has completely dried out, without any chance of recovering anytime in the future.
Lake Poopó used to have a permanent lake body of 1,000 km2. It was 92 kilometers long and 32 kilometers wide, occupying the eastern half of the Oruro Department, one of the most important mining regions of Bolivia. The lake’s main tributary was the Desaguadero River, from which it gained 92% of the water, which was flowing in from Lake Titicaca, situated at the northern end of the Altiplano. Lake Poopó only had an average depth of 3 meters, making it more prone to evaporation and variations in surface area.
During times of very high water levels, the lake was connected to Salar de Coipasa salt desert towards the west. The lake has been officially classified as endorheic, as it lacks major outlets.
Studies have shown that the longest period in recent times with a continuously-existing water body was between 1975 and 1992. According to scientists, Poopo has reached its maximum size in 1986, with a surface of 3,500 km2. This was followed by a steady decrease in levels until 1994, when it completely disappeared. Complete dry-ups have been witnessed many times throughout the lake’s history, followed by slow but steady recoveries. But specialists proclaim that it will not be a happy ending this time.
Titicaca’s low water levels directly affect Lake Poopó, since the Deseguadero River cannot compensate for the massive water loss caused by evaporation. The heavy rainfalls during the mid ‘90’s helped revitalize the lake again. With some funding from the European Union, efforts have been made to make the whole area ecologically sustainable. However, due to a temperature rise of 0.9OC which have tripled evaporation rates, these attempts have been unsuccessful.
In 2002 the lake area was categorized a site of conservation under the Ramsar Convention. As of the 20th of January 2016 the area has been declared a disaster zone by the Bolivian government and any hope of revitalizing Lake Poopó has perished.
Geology and Composition
Because of the lake’s endorheic nature the weathered ions remain in entirety in Poopó’s system. The lake’s high salinity varies with the water volume and is caused not only by its lack of outlet, but also by the high evaporation rate and the arid climate.
A research conducted between October and November 2006 concluded that the lake’s salinity at its northern end was between brackish and saline (between 15,000 and 30,000 mg/l), whilst the southern end was brine (between 105,000-125,000 mg/l). It has also been shown that geological sources of NaCl like halite and feldspars can also be found in the drainage area.
The lake body of Poopó is situated atop of Cenozoic deposits, generally made up of unconsolidated material. These deposits are the remains of old and extensive prehistoric lakes, which used to govern the area during 5 glaciation periods.
A study of environmental degradation displays exceptionally high capacities of lead, copper, silver, cadmium, cobalt, nickel, chromium, tin, iron, manganese, antimony and zinc. For example, the lake’s lead concentration is 300 times higher than the average capacity of the world’s lakes.
Flora and Fauna
The lake was abundant in 3 native fish species: the Mauri, the Carache and the Ispi. 2 exotic fish have been introduced in 1955, the rainbow trout and the silversides Odontesthes Bonariensis, which were much bigger than the native fish, thus commercially more important. Lake Poopó had a relatively large fish population, which dwindled with the decline of water.
The aquatic bird life used to be highly diverse, boasting over 34 different species. The most familiar ones were three types of flamingos which lived in shallow lagoons in the northeastern part of the lake. BirdLife International made an inventory of the bird population in 2000 and discovered 6 endangered species, among which were the Chilean Flamingo and the Andean Condor.
17 different types of superior plants and 3 species of algae have been identified in and around Lake Poopó. Due to the constant environmental distress, the whole area has witnessed great disturbances, resulting in the disappearance of nearly all vegetation on the lakeshore. Cacti reaching up to 5 meters can still be seen.
Unique Weather Phenomena
The Titicaca-Desaguadero-Poopó-Salar area has constantly suffered from climate change, witnessing flood losses and the harsh effects of droughts. This has directly increased the frequency of El Nino, an oceanic phenomenon which produces extreme drought in some regions and abundance of rain in others. The TDPS area is part of the former.
The Dire Consequences of Mining
The area around Lake Poopó has always been a popular mining area. Excavation of heavy metals began as early as the 13th century with the aim of supporting the Inca army. After the Spanish colonization in the 16th century, they began operating at a larger scale and the area soon began identifying as one of the largest mining centers in Bolivia. The main mining districts were located east of Lake Poopó, at the foothills of Cordillera Oriental.
The metals located in the bedrock are extracted through a weathering process, which causes heavy metal pollution in the area. The acid leaching from the mines and the mechanical processing of ore all contribute to severe pollution. Studies have shown that arsenic, lead and cadmium concentrations in the waters of the lake exceeded Bolivian and the World Health Organization’s guidelines for drinking water, and have also been limited for agricultural use.
Today mining is Bolivia’s second export earner after natural gas.
A team from the San Andrés University of La Paz has conducted research in the area, showcasing the influence of the Wankarani culture on the Poopó basin between 200 BCE and 200 CE, during the Late Formative Period. They also determined that llama caravan merchants and herders coexisted with local sedentary farmers.
After examining the period between 300 and 900 CE called the Early Regional Developments period, they have come to the conclusion that the size of the inhabited areas around Lake Poopó have increased. The area’s inhabitants are known for its uniquely-styled ceramics decorated with triangular spirals. On the eastern border of the lake an important Tiwanaku enclave has been displayed, with ceramic styles typical of the Titicaca area, emphasizing the interaction between various people living in the region.
Low Level of Economic Development and Poverty
Lake Poopó had a key part in local living, as many lived from fishing. Due to the exacerbated drought and unkind weather conditions, many have relocated. The lack of permanent jobs, the low access to basic services and the low institutional capacity all resulted in extreme and marginal poverty in the area. The local Uru Moratos based their living on fishing and hunting, with both activities disappearing after the lake’s disastrous disappearance. The environmental effects caused lower agricultural production and productivity. Illiteracy was 16% higher than the departmental average and infectious diseases of environmental origins have also governed the area.