This year's floods will not be as catastrophic as the ones in 2011 due to smaller masses of water coming from the North and the country's readiness to deal with the disaster, water expert Chawalit Chantararat predicts.
Mr Chawalit, director of Team Consulting Engineering and Management Public Company Limited (Team Group), recently told the Bangkok Post he is optimistic this year's rainfall will be manageable.
He said that although heavy rain has fallen in the northern provinces, including Chiang Rai, Phayao, Phrae, Sukhothai and Phichit, it has not been enough to flood the whole region.
He also noted the amount of water flowing past Muang district of Nakhon Sawan province this year is 15.6 billion cubic metres. In contrast, the highest amount measured on Sept 25, 2011, was 23.4 billion cubic metres.
He said the huge volumes seen in 2011 were due to the four main rivers that flow from the northern region (the Ping, Wang, Yom and Nan Rivers), which meet at Nakhon Sawan, the origin of the Chao Phraya River. This year, however, only the Yom River brought excessive water from the North. "The mass of water flowing through Nakhon Sawan on Aug 25 was about 40% of 2011's amount, which is manageable," he said.
Chawalit ChantararatWhen asked whether he was certain Bangkok would not be hit by a flood like in 2011, Mr Chawalit, also a water resources engineer, said that based on current volumes, there should not be any problem because the city is where the exit to the sea is located, and the water mass in the North does not cover a vast area.
He also expressed confidence in the 10 kaem ling or "monkey cheek" water catchment areas along the Chao Phraya River, located in provinces north of Bangkok, including Ayutthaya, Lop Buri and Ang Thong.
These reservoirs can hold 1.2 billion cubic metres of water and will prevent the northern water from reaching Bangkok, he said.
"Bangkok usually fails to drain rainwater after heavy rain in some areas due to the city's basin land, especially the 12 risk areas, such as Chaeng Watthana Road [from the Prapa Canal to the Prem Prachakon Canal], Ratchadaphisek Road [in front of Bangkok Bank] and Sathu Pradit Road [the Sathu-Chan junction]", Mr Chawalit said.
He said it is usually difficult to release rainwater into the Chao Phraya River in October when the sea level is normally high, as this can cause floods in areas outside the flood-prevention zone, such as the Soi Si Kham community in Samsen Soi 19, the Devaraj Kunchon community and the Rachaphatubtim Ruam Jai community in Dusit district, in addition to Phra Nakhon district's Tha Wang and Tha Tian areas and Yannawa district's Rong Si community on Rama III Road.
According to Mr Chawalit, another important factor that contributes to floods is global warming, which was one of the reasons that caused excessive rainfall in Bangkok in 2022 when the city saw 800 millimetres of rainfall in a single month while the whole year's rainfall was only 2,300 millimetres.
"Global warming is getting closer to us. The Earth's temperature should not rise by over 1.5 degrees Celsius, but it has now gone up by 1.2C.
"If it reaches 1.5C, more disasters, such as wildfires, floods, the melting of polar ice and overflows of seawater into rivers, will occur," he said.
In the next 26 years, sea levels in the Gulf of Thailand will rise by 75cm, which is the number the Intergovernmental Panel on Climate Change predicts, he said. "By then, Bangkok may be submerged," said the water expert.