Indigenous Aymara youth are using ancestral knowledge to address current-day pollution and climate change affecting Bolivia’s Lake Uru Uru. The youth, who formed a group called the Uru Uru Team, are blending Indigenous knowledge with modern phytoremediation, producing rafts of plants to improve water quality in the heavily polluted lake.

Located in Bolivia’s Puna region at an altitude of over 3,600 meters (11,800 feet), Lake Uru Uru has been a key local water source since it was formed in 1962 when sedimentation shifted the course of the Desaguadero River. Given the importance of their watershed to the regional ecosystem and Indigenous communities, Lake Uru Uru and Lake Poopó, a larger water body located 72 kilometers (45 miles) south, were together declared a Ramsar Wetland of International Importance in 2002. But Lake Poopó dried up a decade ago, and Lake Uru Uru has shriveled to a small fraction of its former volume—changes experts attribute mainly to global warming and diversions of water for mining and agriculture.

Lake Uru Uru has received heavy metals and acid runoff from nearby gold and tin mines, as well as liquid and solid waste from Oruro, a city on its northern banks. An estimated 400 mines dot the Uru Uru and Poopó lakes region, many of them Chinese-owned.

The lake and its shores have been home to plants including the opuntia and trichocereus cacti and animals ranging from pumas to flamingos, but pollution and shrinkage of the water body have taken a toll.

“We used to see an abundance of flamingos flying over our lake, but few have survived these polluted waters,” says Dayana Blanco Quiroga, who co-founded the Uru Uru Team in 2019 with 14 friends whose ages now range from 20 to 26. “We didn’t have a penny in our pockets, so we improvised with resources we had available and, informed by our ancestral Indigenous knowledge, came up with a way to reverse the damage.”

Blanco, who has a degree in international commerce from the Indigenous Technical University of Oruro, is among the first generation of women in her family with formal education. She says community elders passed down knowledge of the natural filtration ability of totora plants growing in the regional watershed.

The plant (Schoenoplectus californicus) has traditionally served many purposes in the region, including as a key material in the construction of boats and of floating platforms for dwellings.

“The wise elders from our community would tell us how they used plants to filter and clean water,” Blanco says. “Our generation has combined this knowledge with educational and technical know-how to come up with solutions for modern day threats to the lake.”

Ambitious aim

So far the team has restored six square kilometers (over two sq. miles) of the lake by positioning rafts of totora plants in key locations where engineers advising them say they will do most to capture incoming pollutants.

Their aim is to put out enough of the phytoremediation rafts to serve the entire lake, which originally covered 250 square kilometers (97 sq. miles) but has shrunken to an estimated 10 square kilometers (3.9 sq. miles). They hope this and other initiatives—particularly curbing water diversions to the mining industry—will help restore the lake’s size and water quality.

The Uru Uru Team makes rafts from recycled plastic bottles discarded in Oruro, fashioning them into floating totora planters. The totoras’ roots reach the water through holes in the decking and around the platforms’ edges. As natural reefs of totora traditionally did in shallow waters, the raft-borne plants filter pollutants and sediment, scientists say, significantly improving water quality.

The team’s project began in 2020, when a plan for it won third place in Bolivia’s Youth Water Competition, organized by Unicef Bolivia and the Swedish Embassy to recognize water-conservation solutions. The team received financial support to develop a prototype platform, along with technical support, implementation resources, and communications assistance from Gaia Pacha Foundation, a Bolivian environmental nonprofit.

“We are creating sustainability among adolescents and youth,” says Rodrigo Meruvia, founder and coordinator of the foundation. “The issue is not just access to water and conservation of water bodies, but also hygiene, drainage and sanitation. We need a broad approach to the culture of water.”

Laboratory studies show that in areas of the lake where rafts have been placed, water pollution has been reduced by 30%. Meruvia points out that aside from deploying rafts of live totora, the Uru Uru Team has started a community garden to raise money for maintenance of the rafts. It has also educated Oruro residents to reduce the flow of trash and other municipal waste into the lake—a significant pollution source in addition to mining waste.

Government buy-in needed

Meruvia believes long-term progress will hinge on strong government commitment.

“Bolivia’s civil organizations fill the gaps in responsibility and action that the municipal, state and national levels of government leave unattended,” he says. “The authorities should be regulating and monitoring the area to minimize impact. Instead, civil society is picking up the pieces and raising awareness. Hopefully in the long run a critical mass could generate pressure for governments to take action in the future.”

The Uru Uru Team has organized peaceful protests and legal action highlighting the impacts of mining. In its outreach efforts, it has established contact with 1,000 local residents.Still, leaders of the seven indigenous communities near Lake Uru Uru worry that if the region’s mines are not subject to local restrictions, the lake will suffer the same fate as Lake Poopó.

Blanco’s vision for the future is to clean up the entire lake, implement environmental education in the communities and build a laboratory where the power of plants to regenerate the environment can be documented.

“Science invalidates Indigenous knowledge, so it is important for [scientific] institutions to validate the [positive] impacts so they are recognized and wisdom is recognized and conserved for future generations,” she says. “The authorities have failed to offer any responses, so we kicked into action, backed by the strength of our community.”