People living near the Chao Phraya River in Bangkok and in ten other central provinces are being warned, by the Irrigation Department, of overflows from the river starting Wednesday (July 27th), due to the discharge of excess water through the Chao Phraya Dam.

Irrigation Department Director-General Praphit Chanma said today (Monday) that a large volume of water, flowing at a rate of between 1,050-1,150m3/sec, produced by rainfall between July 20th and 24th, in the Nan river basin and its Kwae Noi and Pasak tributaries, is expected to arrive in the Chao Phraya reservoir, making it necessary to increase the discharge rate to between 850 and 1,000m3/second.

This will increase the level of the river downstream of the dam by between 60 and 80 cm, which is likely to breach the banks and flood low-lying areas in 11 provinces, such as Uthai Thani, Chainat, Sing Buri, Ang Thong, Ayutthaya, Suphan Buri, Lop Buri, Pathum Thani, Nonthaburi, Samut Prakan and Bangkok, he said.

The most vulnerable areas will those beyond the protection of floodwalls, such as Pong Peng canal in Ang Thong, Bang Bancanal in Ayutthaya, Hua Wiang, Sena, Ladchid and ThaDindaeng sub-districts of Pak Hai district of Ayutthaya, said the irrigation chief.