BANGKOK, Thailand – The Thai government says the Chao Phraya River basin still has substantial capacity to accommodate additional water, with four major reservoirs able to hold a combined 9.999 billion cubic metres, while the river level at Nakhon Sawan remains well below its banks. Government spokesperson Lalida Phiritswiwatana said Monday that authorities are closely monitoring water conditions throughout the Chao Phraya basin during the rainy season. Data recorded on Aug. 23 showed that water flowing through the C.2 monitoring station in Nakhon Sawan had risen to 798 cubic metres per second, up from 648 cubic metres per second the previous day.
espite the increase, the water level at the station remained 6.62 metres below the riverbank, indicating that there was still considerable room before the river reached critical levels. The government is also monitoring four major reservoirs — Bhumibol, Sirikit, Khwae Noi Bamrung Dan and Pasak Jolasid dams. Their combined storage stood at 14.783 billion cubic metres, or around 60% of total capacity, leaving another 9.999 billion cubic metres of available storage. Lalida said authorities were monitoring eight provinces in the central Chao Phraya basin — Sing Buri, Ang Thong, Phra Nakhon Si Ayutthaya, Lop Buri, Saraburi, Pathum Thani, Nonthaburi and Samut Prakan — together with Bangkok.
No flooding had been reported in those areas as of Aug. 23. However, authorities will continue monitoring rainfall and river levels throughout the rainy season to ensure water management measures and public warnings can be implemented quickly if conditions change. In the lower Chao Phraya basin, water passing through Sam Khok district in Pathum Thani had increased to 268 cubic metres per second from 166 cubic metres per second a day earlier. At the same time, 186 cubic metres per second was being diverted into the eastern irrigation system and 211 cubic metres per second into the western system as part of ongoing basin-wide water management.
Lalida stressed that increases in water flow at individual monitoring points must be considered alongside river levels and the remaining storage capacity. She said authorities were assessing rainfall, upstream runoff, river levels and available retention areas together rather than relying on a single measurement. The government is also keeping a close watch on weather conditions. Thailand is experiencing thunderstorms and locally heavy rain under the influence of a monsoon trough, while Tropical Storm Narra over the Gulf of Tonkin is forecast to move ashore in China’s Guangxi region on Aug. 24–25. The storm is not expected to move directly into Thailand or have a major direct impact on the country’s overall weather.
Residents, particularly those living along rivers, in low-lying areas and in locations prone to repeated flooding, have been urged to follow official weather and water updates and prepare for possible changes in conditions. Preparations were also discussed at a meeting of the subcommittee responsible for flood and drought prevention and response in the Chao Phraya basin on Aug. 23. The meeting was chaired by Tourism and Sports Minister Surasak Phancharoenvorakul, with Minister attached to the Prime Minister’s Office Pharadon Prisananantakul serving as an adviser, together with relevant agencies and local authorities.
The government said continued monitoring and advance preparation would remain priorities throughout the rainy season. The Chao Phraya is Thailand’s principal river system, running south from Nakhon Sawan through the central plains and Bangkok before reaching the Gulf of Thailand.
