More water discharged from Chinese dams to the lower Mekong River in the dry season and less water in the rainy season. That means a reduction of drought and flooding in the lower Mekong countries. That was the ideal "cooperation" Thailand, Laos, Cambodia and Vietnam expected from China. In reality, China seems to have done the opposite.
A new study, conducted by Eyes on Earth Inc, vividly points out that China turned off its taps on the upper stretches of the river last year as it enjoyed higher than usual precipitation due to heavy rainfall and snowmelt. Its action resulted in an unusually severe drought in the four Mekong countries downstream.
Citing data derived from satellite imagery, remote sensing processes and water levels gauged on a stretch of the Mekong in Thailand's Chiang Rai province, the study shows that from April to September 2019 China's 11 dams blocked or restricted water more than ever before, causing the lowest water levels in 50 years on the lower Mekong. Had it let the water run its course, the four countries could have enjoyed above-average water volume.
The study also shows that the 11 Chinese dams have stored a high volume of water over the past three decades.
China has never been open about how much water it has withheld or released from its reservoirs since it started building dams on the Mekong, known as Lancang there, in the 1990s.
In the wake of the study released on Monday, China disputed the findings, insisting it has guaranteed a reasonable discharge of water. Nobody will buy its defence as long as it offers no transparency on its use of Mekong water upstream. If China wants to prove it did not impound water at the cost of Thai, Lao, Cambodian and Vietnamese people, it should have shared comprehensive information on its storage and discharge of water.
The findings from the study have indicated that sudden floods on the lower Mekong in the past years could be attributed to China's regulation of the Mekong flow -- discharging overabundant water to avoid floods in the Lancang stretches.
Since China started building dams, many worried that it could impound water from the downstream countries whose citizens rely on the river as their sources of food and income. When Thailand, Laos, Cambodia and Vietnam formed the Mekong River Commission (MRC) to cooperate on development in the basin, China did not join it. Beijing merely became a "Dialogue Partner" of the MRC from 2002. And its only tangible cooperation with the MRC is the sharing of data on water levels from its two monitoring stations on the Lancang only during the wet season.
True, the rise in the severity and frequency of drought and floods on the lower Mekong could also be partly caused by the changing climate. But the study shows that it was largely caused by China stocking up on water.
Becoming an MRC member could have forced China to be more transparent about its water use and share all information on its water levels. China must have been aware that it would mean opening a Pandora's box. So it established the so-called Mekong-Lancang Cooperation, an alternative platform which it can control and manipulate.
Given that it has expanded its trade and geopolitical power in Thailand, Laos and Cambodia, China should have treated these countries as its partners and friends by starting to tell them exactly how much water it has been impounding and discharging from the mighty Mekong.
