Huge volumes of water being discharged from a hydropower dam on the Mekong River in southern China’s Yunnan province have placed the country’s downstream neighbors on high alert amid concerns over possible flash floods.
Officials in Laos, Thailand, and Cambodia are closely monitoring levels of the Southeast Asian artery after being informed by Beijing that the 1,750-megawatt Jinghong dam will need to release a huge volume of water downstream from Sept. 5-30 due to heavy rain upstream.
A provincial official of the Lao Ministry of Natural Resources and Environment told RFA’s Lao Service that China informed Vientiane on Sept. 1 about the release of water from the reservoir in the Jinghong dam in the upper half of Mekong known in China as Lanchang River.
While the water release has yet to cause any flooding in Laos, the official in Bokeo province warned Monday that water levels had already risen on the Mekong in the provincial capital of Houayxay.
“The water level measured at Houayxay station is now over six meters (20 feet),” said the official, who spoke on condition of anonymity.
He said that the water release could “add three more meters (10 feet)” to the level of the Mekong if the amount of discharge is increased, without specifying when or by how much, but added that the Houayxay region is not in danger of flooding until the river reaches 16 meters (52.5 feet).
The Chinese dam on the mainstream of the Mekong is currently discharging water at a rate of 535 cubic meters per second from the reservoir, which is estimated to contain 591-602 million cubic meters, Thailand’s The Nation reported Monday.
The Jinghong dam has a maximum discharge capacity of 9,000 cubic meters per second which could result in a rise of the Mekong by three meters (10 feet) in Thailand’s Chiang Rai province within days, it said, citing Songklod Duanghaklang, director of the Chiang Rai Marine Office.
Global environmental group International Rivers warned that such water releases could result in disaster.
"In the Mekong River Basin, water releases from dams compounded with heavy rainfalls, can make for disastrous consequences," International Rivers Southeast Asia Program Director Ame Trandem told RFA.
She said Hydrolancang, the primary developer on the main stem of the Upper Mekong River, and the Chinese government "should be responsible for compensating all people in the basin who are impacted by any flooding caused by the Jinghong Dam."
Te Navuth, secretary-general of the Cambodia National Mekong Committee, told RFA’s Khmer Service that the committee had not observed any significant change in water level on the river, suggesting that discharge from the Jinghong dam would not lead to flooding in Cambodia.
“Our station which monitors the water levels on the Mekong River near the Golden Triangle Area between Thailand, Laos, and Myanmar has not reported [any major] increase,” he said.
“There is enough [of an increase to be] noticeable, but there is no evidence that the water is coming from China.”
Te Navuth said that Cambodia lies about 2,000 kilometers (1,245 miles) downstream from the Jinghong dam, suggesting that the country would not be affected by flooding as a result of the release.
He added that it is a standard operating procedure for dams to discharge water.
However, Meach Mean, coordinator of 3S Rivers Protection Network, told RFA that the level of the Mekong in Cambodia—as well as its fish population and water quality—would face some adverse effects from the Jinghong water release.
“Cambodia will be affected, depending on the volume of water being released from the dam,” he said.
According to the Phnom Penh Post, no flood warnings have been issued in Cambodia so far, as none of the country’s water monitoring stations have indicated a rise to alert levels.
But the Post cited experts as saying that flash floods remain a concern when upstream dams discharge water in combination with the heavy rains of the ongoing wet season.
Reported by Samean Yun for RFA’s Khmer Service and RFA’s Lao Service. Translated by Samean Yun and Somnet Inthapannha. Written in English by Joshua Lipes.