Little is known about the water quality of Asia’s major rivers that drain the Tibetan Plateau, even though these rivers play a significant role in the lives of more than one third of the world’s population. But public concern is mounting over the effects of rapid economic development on the Plateau’s supposedly pristine waters.
University of Eastern Finland PhD student, Huang Xiang, has shed light on this murky question by carrying out the first systematic study on the water quality of major rivers of the Tibetan plateau. She examined the chemical quality of river water in order to identify the natural and human sources of contamination.
Huang’s supervisor, Professor Mika Sillanpää, presented the research at an event at the London School of Oriental and African Studies this month. Her research reveals that though natural processes of chemical weathering and anthropogenic climate change play a part –increased mining activities pose the greatest threat to local and downstream water quality.
The Tibetan Plateau boasts a bounty of mineral deposits, including copper, lithium, iron, boron and gold. Nearly 25 years of industrial scale mining operations - carried out under a shroud of poor planning and inadequate waste management - have already tainted regional water supplies. However, no information about the pollution has been provided to the public.
In recent years, large scale mining activities have intensified in the wake of the construction of new Qinghai-Tibetan rail links, as discussed in a recent chinadialogue article. By 2007 there were 66 domestic mining operations registered in Tibet; by 2010 there were over 100. And more are to come.
Tibet’s mining industry is a high priority for central government concerned about general supply shortage. In March this year, Beijing announced plans to exploit over 3,000 mineral reserves, potentially worth more than US$ 125 billion. The mining industry currently represents 3% of the local economy, but is predicted to rise to 50% by 2050.
Mining poses an even greater threat because mineral processing factories are also located within the major river catchments in the Plateau. Huang’s study identifies severe heavy metal pollution in a major tributary of the Yarlung Tsangpo in the Gyama Valley - caused by poorly regulated mining operations and a complete lack of proper waste treatment facilities. High levels of Aluminium, zinc and copper have contaminated water supplies causing the death of livestock and illness among local people. This tributary flows through the most intensively mined area of Tibet, and into the Lhasa River, which provides drinking water to the Tibetan capital, Lhasa.
Sillanpää explained that while mining has already caused heavy metal contamination in the upper reaches of Tibet’s rivers disappears; pollution is diluted further downstream due to the rapid precipitation of metals in Tibet’s high alkaline river waters. This explains why water contamination has remained so localised to date. But given that mining activities will grow at a gargantuan scale, the lack of regulation and sufficient waste management systems, the flow of pollution will spread swiftly in years to come.
Finally, Huang highlights three essential areas of future research:
1. Monitor the changing chemical concentration in contaminated water and sediments
2. Set up a water quality monitoring program targeting the effect of mining activities
3. Study the impact of natural processes – erosion, weathering and drainage from saline lakes and geothermal springs - on chemical changes in Tibetan rivers.
Such research is invaluable; but whether the relevant authorities can be persuaded to acknowledge and act upon these findings is the crucial, more shadowy question.