The uncontrolled dumping of sewage waste and tailings produced by more than 30,000 small-scale miners are causing widespread environmental damage in Lake Titicaca, the largest lake in South America and the highest commercially navigable lake in the world.
“Everything drains into the lake,” said Alberto Giesecke, a scientist and spokesperson for Peru’s Environment Ministry. “It’s not only sewage from homes, but from hospitals, factories and slaughterhouses,” he said in comments to daily El Comercio, published Monday. “Without sewage treatment facilities, this lake is doomed.”
Tucked away high in the Andes between snow-covered peaks, Lake Titicaca, which straddles between Bolivia and Peru, is being asphyxiated by pollution. According to Peru’s Environment Ministry, more than 12 million cubic meters of sewage water are dumped into Lake Titicaca every year.
The city-fed pollution can be traced back to the 1980s, when foul odors first emanated from the lake and schools of fish turned belly-up. The untreated waste water has triggered what scientists term “eutrification,” or the process by which oxygen is removed from the water by the decomposition of large amounts of organic matter.
Tiny water lentils, or lemna gibba, fed by sewage emptying into the lake, pose a particular health and economic problem and have turned the lake a milkshake-like shade of lime green in some areas. More than four truckloads are removed from the lake daily, and more than 800,000 tons yearly.
“The water lentil is a synonym of pollution,” said Edmundo Mirando, Director of Puno’s Interior Bahia Program. “Unfortunately, collecting it doesn’t solve anything because all the waste and organic matter that has accumulated at the bottom of the lake remains, and continues to grow.”
According to a scientific study carried out last December by Peru’s Ocean Institute, or Imarpe, proteins and mercury have been detected in the lake’s fish.
Although the quantities have yet to surpass the 0.3 mg/kg limits set by the Environmental Protection Agency, mercury — even in small quantities — affects people’s health, said Renato Guevara, Imarpe’s Director.
“Mercury accumulates in the food chain,” said Guevara. “First, in the zooplankton, which is then eaten by small fish. These feed larger fish, like the pejerrey.”
Besides receiving sewage and industrial waste from the city of Puno, Lake Titicaca receives agricultural run-offs from the surrounding areas and tailings from mineral processing plants and the region’s more than 30,000 informal miners. During the dry season, the Katari, Ramis, Seco, Seque, Pallina and Jalaqueri rivers deposit trash and metal contaminants they pick up from cities and towns along their banks.
Small-scale mining poses a complicated problem for Peru because of its social, political and economic nature. Any solutions to the negative consequences it generates must take into account the sanitary and environmental impacts of poverty, the needs of small-scale miners and their families, the ability of Peruvian authorities to monitor and enforce regulations, and the fact that large mines often compete with small-scale miners for access to mineral deposits and land.
For poor people living along Lake Titicaca’s shores and in small mining towns further upriver on the banks of the Ramis, the struggle to survive often takes precedence over protecting the environment.
According to the Foundation for Sustainable Development, “the severe contamination of the lake affects the health of those who depend on it, yet systems of monitoring and testing water quality are primitive, under funded, and falling behind the current rate of pollution.”
And, since violence and terrorism have long prevented environmental issues from being at the vanguard of community debate, it is only now that they are being addressed. The Lake, for example, is still managed by Peru’s Agriculture Ministry rather than the recently created Environment Ministry.
The impact of tourism on the environment, mainly in terms of depletion of water, soil and air quality, is also becoming increasingly significant in the region. Soil erosion threatens the region as well, reports World Lakes, as more than a quarter of total watershed area is considered vulnerable to erosion.
