The Irrigation Department spokesperson confirmed that flooding will not be as severe as in 2011 and will differ from 2015 as well. The department aims to discharge no more than 1,800 cubic meters per second, diverting water into left and right branch canals, and draining water in preparation for late September rains. Regarding concerns in Bangkok, if heavy rains occur, there is a high possibility of water accumulating and awaiting drainage, especially in low-lying areas with a history of waterlogging.
On 23 September 2026, Dr. Thanet Somboon, Director of the Water Management and Hydrology Division and spokesperson for the Royal Irrigation Department, stated that for the monsoon passing through Thailand, the department has planned water management. Initially, water comes from Nakhon Sawan Province via the Ping, Wang, Yom, and Nan rivers, with rainfall since last week at the tail of the Bhumibol Dam in Kamphaeng Phet, the Sirikit Dam, and areas in Phitsanulok and Phichit provinces, causing water masses to converge.
The Irrigation Department has assessed existing water volumes and is using irrigation systems to push water into branch canals of the eastern and western regions, such as Pasak Canal, Chainat-Ayutthaya Canal, to discharge into the Chao Phraya River. Water discharge into the department’s system considers the impact on local residents.
Following a joint meeting with the Department of Water Resources, permission was requested to discharge 1,500 to 2,000 cubic meters per second. Residents might be alarmed by the possibility of discharges reaching 2,000 cubic meters per second. However, the request is a contingency plan, and actual discharge is expected not to exceed 1,800 cubic meters per second based on current assessments.
Regarding provinces with repeated flooding history causing concern, Dr. Thanet acknowledged that Phra Nakhon Si Ayutthaya Province, particularly Bang Ban district, normally discharges about 700 cubic meters per second, resulting in water levels over one meter. While residents worry about a repeat of 2011 flooding, he assured that the situation will not be the same as in 2011 or 2015.
Rainfall is expected from late September to early October 2026, possibly marking the last phase of flooding in Central Thailand. If no significant additional rainfall occurs, water discharge volumes will decrease.
Regarding concerns in central Bangkok, many worry about waterlogging awaiting drainage in various areas. Dr. Thanet explained that Bangkok’s drainage system can handle only up to 60 millimeters of rain per hour. If heavy rainfall exceeds this, waterlogging is highly likely, especially in low-lying areas with a history of flooding.
From meetings with Bangkok authorities, it is known that water levels have been lowered in Saen Saep Canal and other canals to create capacity. Pumps are also used to push water out of flooded areas. This effort aims to prevent flooding as severe as in 2011.