The National Water Resources Office (NWRO) has announced close monitoring of a sudden water level increase in the Mekong River, forecasting a rise of 2 to 4.8 meters from 31 August to 6 September 2026. Eight provinces along the Mekong are urged to prepare for potential bank overflows.
On 31 August 2026, the Facebook pageof the National Water Resources Officeposted an announcement titled: National Water Resources Office Announcement No. 2/2569 regarding the forecasted rise and overflow risk of the Mekong River water level.
The NWRO has been monitoring the Mekong River situation and found that the influence of the monsoon trough will move over northern and upper northeastern Thailand, reaching a depression over southern China. Meanwhile, the southwest monsoon blowing over the Andaman Sea, Thailand, and the Gulf of Thailand is quite strong. This will result in heavy rainfall from 31 August to 2 September 2026 in the upper areas of the Lao PDR, northern Thailand, and northeastern Thailand. Additionally, on 31 August 2026, the flow through the Xayaburi Dam is expected to reach about 18,000 cubic meters per second.
This will cause the Mekong River water level to rise continuously. The NWRO forecasts the water level trend along eight Mekong-border provinces from Chiang Saen District, Chiang Rai Province, to Khong Chiam District, Ubon Ratchathani Province, for the five days from 31 August to 6 September 2026. Most locations are expected to see increases of about 2.0 to 4.8 meters, with water levels exceeding critical thresholds and flooding particularly in low-lying areas along the Mekong in Nong Khai, Bueng Kan, Nakhon Phanom, and Mukdahan provinces, as follows.
1. Nong Khai Station In Mueang Nong Khai District, Nong Khai Province, water levels are expected to exceed the critical level from 2 to 4 September 2026, with the peak on 4 September exceeding the critical level by 0.28 meters.
2. Bueng Kan Station In Mueang Bueng Kan District, Bueng Kan Province, water levels are expected to exceed the critical level from 2 to 5 September 2026, with the peak on 5 September exceeding the critical level by 1.22 meters.
All relevant agencies in provinces along the Mekong River are urged to prepare for potential bank overflows and flooding, especially in low-lying areas along the river.
Also, in tributary areas of Thailand where water cannot easily drain into the Mekong River, authorities are requested to publicize water situation updates and warn residents and people conducting activities along the Mekong River to closely monitor the water conditions and prepare for possible impacts from fluctuations in the Mekong River water levels.
Information courtesy of the National Water Resources Office's Facebook page.