HONG KONG—China’s lack of transparency about the potential environmental impact of its dams on the Mekong River may have disastrous results on downstream communities, according to an environmental expert.
Li Yucheng, a researcher with Globalization, a Hong Kong-based NGO that has conducted a long-term ecological study on the Mekong River, said water levels on the Mekong are the lowest in nearly 30 years.
Li Yucheng said dams on the Mekong River have had some impact on the ecological environment, but added that China’s lack of transparency on the development of its hydropower projects makes it difficult to scientifically assess that impact.
“In our observation, it is difficult to rule out the relationship between the two, because of the Chinese government's failure to disclose related hydrological information, in particular about the four dams on the Mekong River,” Li said.
“China is concerned that to disclose this information would give away national security and state secrets, and therefore the government is reluctant to share it,” he said.
China’s four dams include the Man Wan, Wave Hill, Jinghong, and Little Bay dams. While Little Bay only generates energy for local consumption, the other three dams are fully operational.
Li Yucheng called on the Chinese government to disclose more information to countries downstream along the Mekong River, including studies on the impact of its dam projects.
“Upstream and downstream water resources should be shared, so we think that the Chinese government should increase its transparency and disclosure to the downstream countries, especially regarding water discharge and reservoir levels of the four dams,” he said.
Li Yucheng noted that, in addition to the four dams, China is planning 11 dam projects in upstream regions, in addition to one dam along the Sino-Burmese border.
Ten of the dams are expected to be completed within 10 years, he said.
Rebuttal of claims
On Monday leaders from Thailand, Cambodia, Vietnam, and Laos met in
the Thai coastal town of Hua Hin to discuss management of the Mekong
River, which supports nearly 65 million people on its way to the South
In Lower Mekong countries, many view the drop in water levels as a result of the construction of hydropower stations upstream in China.
But Chinese vice foreign minister Song Tao refuted the claims,
saying that drought, and not China's dams, is to blame for the low
Song said drought in southwestern China has left about 18 million people and 11 million animals with insufficient drinking water, and has affected 4.3 million hectares (10.6 million acres) of crops.
"Statistics show the recent drought that hit the whole river basin is attributable to the extreme dry weather, and the water level decline of the Mekong River has nothing to do with the hydropower development," Song said in an official statement after the meeting.
Chinese officials also contend that China’s four completed dams are small and that their water storage capacity is not significant enough to affect the flow of water downstream on the Mekong, though they have offered to share more data with their southern neighbors.
Activists and environmentalists say China has not provided relevant data to assess the impact of the dams on water flows.
But Song said China has provided rainy season data since 2003 and
dry-season data from two hydrological stations since March in response
to requests from four downstream countries through the
intergovernmental Mekong River Commission.
Effects of drought
Drought has spread across the entire southwest border of China. The Mekong River is at its lowest in recent years—less than one meter (three feet) of depth—leaving the more than six million residents of the Lower Mekong Basin without the water they so desperately rely on.
A substantial decrease in rainfall since last September has reduced rice yields in Vietnam and Thailand by one-third.
Low water levels along the Mekong River in Xishuangbanna, in China’s southern Yunnan province, have affected flows through Chiang Rai in northern Thailand and in northern Burma, causing local governments to suspend boat traffic.
Low water levels are also affecting the fishing industry, particularly endangered species such as the Mekong Catfish, which generally spawns in the river during April.
Droughts to worsen
Tibetan Plateau glaciers and lakes provide 8.6 million cubic meters of fresh water to Asia each year. Water flow from the area feeds China's Yellow River and Yangtze River, the Mekong River, and the Ganges in India.
But Yu Xiaogang, director of watershed management for China’s environmental NGOs, said climate change has led to the melting of half of the area’s glaciers over the past few years. If this condition continues, Yu said, droughts such as the one southwest China is currently experiencing will become more frequent.
“In the past four or five years, the glaciers have lost at least half of their present mass. In another 20 years, another half may disappear,” Yu said.
“Much of Tibet's glaciers have melted and much of the water has already flowed away, so the southwest areas of Tibet and China will tend to experience droughts,” he said.
According to Wen Bo, the China program advisor for the U.S.-based Pacific Environment, as the Tibetan glaciers melt, increased water flow along the Mekong River will lead to forest destruction from flooding.
As a result, he said, areas along the Mekong will increasingly be subjected to the two extremes of a drought and flooding cycle.
“The Mekong River’s main source of water is from glacial melt-off, but the glaciers are shrinking and greatly reducing the amount of water upstream,” he said.
“Coupled with climate change caused by deforestation, the Mekong region is likely to experience floods during times of rain and drought when rain is scarce.”
Greenpeace China's Beijing office manager, Yang Ailun, who monitors the organization’s climate and energy projects, said the rapid melting of glaciers will lead to a water level reduction on the Mekong River that will have far-reaching effects, largely on the agricultural production of downstream countries.
“For a very large downstream population that depends on agriculture, glacial run-off is their main source of water for irrigation. The prospects for farming development are worrisome, and farmers are likely to experience a far-reaching impact,” he said.
Yang said worldwide burning of coal and other fossil fuels has led to global warming, which he called the main cause of accelerated glacial melt—a serious threat to the more than 1 billion people who rely on rivers for water in Asia.
Research shows that to avoid the severe consequences of global warming, countries must take the initiative to control their own emissions, Yang said.
Original reporting by Ji Lisi RFA’s Cantonese service. Cantonese service director: Shiny Li. Translated by Joshua Lipes. Written for the Web in English by Joshua Lipes. Edited by Sarah Jackson-Han.