Water levels reach alarm stage at selected cities along the Lower Mekong mainstream
Vientiane, Lao PDR, 29 August 2024 – Persistent and intensified rainfall across the central and upper regions of the Lower Mekong Basin, particularly in northern Thailand and Lao PDR, has caused a significant rise in water levels at critical monitoring stations along mainstream cities over the past two weeks. The water level at Nong Khai station in Thailand has reached flood level today, with similar surges observed at Chiang Khan and Nakhon Phanom in Thailand, as well as in Vientiane and Paksane in Lao PDR.
The Mekong River Commission’s (MRC) monitoring data reveals that sustained heavy rainfall throughout the basin has pushed river levels at most stations above their long-term averages.
Key Monitoring Stations at Alarm Levels:
- Nong Khai Station, Thailand: Water levels reached 12.69 meters today, surpassing the flood level of 12.2 meters. This marks a rise of 0.89 meters over the past five days.
- Chiang Khan Station, Thailand: Water levels have climbed to 15.03 meters, exceeding the alarm level of 14.5 meters. Levels are expected to remain around this threshold for the next few days.
- Vientiane, Lao PDR: River levels have reached 12.11 meters, putting the station in an alarm state. A slight increase is anticipated over the next five days, but levels are expected to stay below the flood warning threshold of 12.5 meters.
The recent rise in the Mekong River’s flow has been influenced by flows from upstream areas. Between 14 and 25 August 2024, heavy rainfall impacted northern Thailand and Lao PDR, causing significant water accumulation in dam storages across the Upper Mekong and the Lao PDR, including Nam Ou 5, 6, and 7, have reached 80% capacity, while storages in Nam Tha 1, Nam Khan 2 and 3 have reached full capacity.
From 15 to 29 August 2024, the water level at Jinhong hydrological station in China ranged from 535.94 to 537.36 meters above sea level. This corresponds to a flow rate of roughly 1,356 to 2,600 cubic meters per second. At the Chiang Saen station in Thailand, the flow increased gradually from 5,200 to 8,900 cubic meters per second between 15 and 26 August, and then fell to 7,200 cubic meters per second by 29 August.
Similarly, at Chiang Khan, the flow increased from about 8,000 to 16,000 cubic meters per second. This increase was a result of upstream water, heavy rainfall, contributions from tributaries in Laos and Thailand, and releases from hydropower stations in Lao PDR (Nam Ou, Nam Khan, and Xayaburi, which is a run-of-river dam, and needs to pass incoming flow further downstream). These flows then moved downstream to Vientiane, Nong Khai, and other stations further along the river.
The MRC has been in communication with the Lancang Mekong Cooperation Water Center as well as the Lao National Mekong Committee, Ministry of Natural Resources and Environment and the Ministry of Energy and Mines. China and Lao PDR have stated that they are carefully managing discharges, although with their reservoirs at near or full capacities, water releases, due to dam safety concern, are inevitable due to heavy rainfall. Today, however, water releases from Jinghong, Nam Ou and therefore Xayaburi Hydropower Projects have decreased than previous days.
Although rainfall is expected to decrease in the coming days, water levels at stations such as Chiang Khan, Vientiane, and Nongkhai will remain high, with Nongkhai staying at the alarm level until the end of the month. Downstream stations like Paksane and Nakhon Phanom may also experience rising water levels in the next five days, with minimum distances to the alarm level of 0.73 meters and 0.37 meters, respectively, and potentially affecting low-lying areas.
Stations in Cambodia and Vietnam currently remain below alarm levels. In the coming week (1-15 September 2024), the lower part of the Lower Mekong Basin may experience heavy rainfall, particularly, the 3S basin – Sekong, Sesan, and Srepok. However, the flood risk at key downstream stations, including Stung Treng, Kratie, and Phnom Penh Port, is projected to remain low. Water levels at these stations likely stay well below alarm and flood thresholds. Over the next month, this low flood risk is expected to continue, with water levels remaining below critical levels.
In accordance with mandate and core function, the MRC and its Flood and Drought Management Center is monitoring the river closely and provides daily updates on the rainfall situation, water level forecast and facilitate cooperation and information sharing on dam operation to the member countries. Different national agencies in the member countries are mandated to prepare and respond to the critical situations in their countries based on their national regulations and processes.
For more information and regular updates on river monitoring and flood forecasting, please visit the MRC’s social media platforms and website at www.mrcmekong.org
Note to Editors
The MRC is an intergovernmental organization established in 1995 to boost regional dialogue and cooperation in the Lower Mekong River Basin. Based on the Mekong Agreement among Cambodia, Lao PDR, Thailand and Viet Nam, the MRC serves as both a regional platform for water diplomacy and a knowledge hub – to manage water resources and support sustainable development of the region.
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For more information, please contact:
Ms. MAO Chandaly
Communication Officer for Press
Mekong River Commission Secretariat
Email: chandaly@mrcmekong.org