The Director-General of the Royal Irrigation Department revealed that the Chao Phraya Dam is set to increase water discharge to between 1,000 and 1,300 cubic meters per second due to the ongoing rise in water flow from the north. He urged residents living in low-lying riverbank areas, outside the flood barriers, and downstream of the Chao Phraya Dam to closely monitor the water situation.
On 20 Sep 2026 GMT+7, Mr. Witthaya Kaewmee, Director-General of the Royal Irrigation Department, announced that. By closely monitoring and analyzing the water situation in the Chao Phraya River Basin, it was found that during 19-20 Sep 2026 GMT+7, heavy rainfall exceeding 100 millimeters occurred in Phrae, Chiang Rai, Kamphaeng Phet, and Sukhothai provinces. This led to increasing water volumes in various tributaries, which flowed downstream to the area above the Chao Phraya Dam, causing water levels there to rise accordingly.
The Royal Irrigation Department finds it necessary to discharge water through the Chao Phraya Dam at a rate of approximately 1,000 to 1,300 cubic meters per second to control the upstream water level, accommodating the floodwaters from upper areas that are still expected to increase. The discharge rate will be adjusted in accordance with the volume of water flowing into the area above the dam.
Areas potentially affected by the increased water levels from discharges through the Chao Phraya Dam at these rates will see water levels downstream rise by approximately 0.50 to 1.50 meters above current levels. This is especially true for low-lying areas outside the flood barriers in Sena, Phak Hai, Bang Ban, Phra Nakhon Si Ayutthaya, Bang Pa-in, and Bang Sai districts of Phra Nakhon Si Ayutthaya province.
However, these water levels do not currently impact communities located within the flood barriers. Therefore, residents living in low-lying riverbank areas, outside the barriers, and downstream of the Chao Phraya Dam are urged to closely follow water updates and warnings from the Royal Irrigation Department and other relevant agencies and to prepare for potentially rising water levels.
Furthermore, all irrigation projects have been instructed to closely monitor the water situation, including inflows from upstream areas, rainfall amounts, water volume, and water levels at various monitoring stations. They will also adjust water management plans to suit the situation, controlling upstream water levels to accommodate floodwater and minimize impacts on residents and agricultural areas.
Should the situation change, the Royal Irrigation Department will promptly inform the public and relevant agencies about updates and water management measures.
