Five River Basins Face Flooding Alert as Dams Near Capacity
Authorities warned residents along five river basins on September 29 to prepare for potential flooding as dams near capacity begin increasing water releases, threatening communities across central Thailand over the coming days.
Decharat Sukhakamneht, director of the Future Policy Center and chair of the Pheu Thai party's water situation taskforce, warned residents along five river basins on September 29, 2026, to monitor conditions closely over the next three days. Although rainfall is decreasing in central and western regions, many upstream dams and reservoirs are at or near capacity and have begun increasing water releases due to supplementary flows from tributaries, threatening riverside communities across multiple provinces.
For the Chao Phraya River, inflows have risen to 2,564 cubic meters per second, raising the level above the Chao Phraya Dam to 17.66 meters. This will affect communities in Chai Nat and Uthai Thani provinces. Current releases from the dam stand at 2,000 cubic meters per second but are expected to increase to 2,200 within days, potentially impacting residents in Chai Nat, Sing Buri, Ang Thong, Ayutthaya, Pathum Thani, and Nonthaburi.
The Pasak Dam is currently at 102.2 percent capacity. Water releases are scheduled to increase from 25 cubic meters per second on September 29 to 115 on September 30, 230 on October 1, and 400 on October 2. The Rama VI Dam will raise downstream releases to 600-700 cubic meters per second from September 28-29, raising water levels in the Pasak River by approximately 1.0-1.2 meters and potentially affecting Saraburi, Ayutthaya, and Pathum Thani residents.
The Tachin River is receiving approximately 600-700 cubic meters per second from combined flows of the Chao Phraya and Mae Klong rivers, exceeding the Tachin's discharge capacity. Flooding has already occurred in several Tachin basin areas, with some locations recording higher levels than in 2025, though still lower than 2011. In the Mae Klong River basin, the Vachiralongkorn Dam holds 94.4 percent capacity and the Srinagarind Dam holds 81.7 percent. Recent heavy rains have added supplementary flows. Current releases from the Mae Klong Dam stand at 1,666 cubic meters per second and may increase to 2,000, potentially affecting low-lying communities in Kanchanaburi and Ratchaburi, though widespread flooding is not expected. Samut Songkhram may experience impacts from tidal influences throughout the day.
