Bangkok Governor Says Water Retention Ponds Not Cost‑Effective
Bangkok Governor Chadchart Sittiput said the city’s planned water retention ponds at Klongbon and Bang Chan would cost 11 billion baht but offer poor drainage efficiency, making them poor value. He noted the projects are not royal initiatives but stem from the city’s own 'monkey cheek' flood‑management concept after the 2011 floods, and that upgrading the existing Nong Bon pond would cost less and hold more water. He also denied any conflict of interest, explaining his former firm’s land opposition was made before his tenure and followed proper procedure.
Chadchart Sittiput, governor of Bangkok, spoke at the Airawat Phatthana Building in Din Daeng on October 7, 2026, explaining the background of the city’s water retention pond projects, especially those at Klongbon and Bang Chan. He said the ponds are part of the Bangkok Metropolitan Administration’s water‑management approach that applies the ‘monkey cheek’ concept based on academic study, not a direct royal project. Decisions must weigh technical suitability, drainage efficiency, and public‑fund value.
He noted that the six ponds originated after the Drainage Office adopted the monkey cheek idea following the severe 2011 floods, with planning beginning in 2013 and the city itself selecting the sites. Consequently, a clear distinction is needed between projects the city undertakes and the genuine royal monkey‑cheek schemes; in Bangkok, places such as Nong Bon pond are linked to the royal concept.
Of the original six ponds, four have already been cancelled after earlier public hearings, leaving only Klongbon and Bang Chan under renewed debate. Consultant analysis shows that building these two ponds, including market‑price land acquisition and related works, would require about 11 billion baht. By contrast, upgrading the existing Nong Bon pond to speed drainage would cost roughly 6.7 billion baht, offering better value for money.
The ponds’ combined storage capacity is about one million cubic metres, but they can realistically hold only around 500 000 cubic metres. During heavy rain, Bangkok may receive up to 350 million cubic metres of water, so relying solely on such ponds is unlikely to be the most effective solution compared with accelerating drainage out of the area.
The governor said the BMA’s current focus is on improving canal performance to move water quickly into existing storage sites with larger capacity, especially Nong Bon pond which holds about five million cubic metres, and on expanding drainage infrastructure so the system can receive and discharge water more swiftly overall.
Regarding allegations of conflict of interest because he once led a real‑estate firm that owned land in the area and objected to land acquisition, Chadchart said that in 2015, while he was CEO, the firm had already purchased the land before the BMA’s public‑consultation process. As an affected party, the company exercised its legal right to object through that process, and no improper benefit was sought.
