Thai Sang Thai Urges Bangkok Plan Review Over Flood Risks

The Thai Sang Thai Party has urged the Bangkok Governor to review the new Bangkok Comprehensive Plan (4th revision), highlighting a fatal flaw: cutting flood retention areas (monkey cheeks) and shrinking floodways, which will permanently heighten the capital's flood risk.

On November 5, 2026, at Bangkok City Hall, party deputy leader Rochin Siribenyaprim, party director Narong Rungthanawong, and party executives submitted a letter to the Governor opposing the draft plan and demanding a review. The letter was received by Asa Thongthammachat, Director of the City Planning and Development Department, and complaint-handling officials.

Rochin stated he was assigned by Khunying Sudarat Keyuraphan, former party leader, in her capacity as a Bangkok resident and stakeholder, to file the objection. The new draft plan neglects the core of flood prevention: water retention areas (monkey cheeks) and floodways. This is a severe flaw that, if uncorrected, will maximize flood risk for Bangkok residents permanently.

Khunying Sudarat's complaint draws on her long experience in Bangkok flood management and the implementation of King Rama IX's royal initiative on the first monkey cheek project at Bueng Makkasan, later expanded to Bueng Nong Bon, which proved effective. Because Bangkok is a tidal floodplain, draining water to the sea is difficult, especially during high tides. Retention areas are essential to hold water until levels drop; without them, floodwater will inundate homes, particularly in older low-lying housing estates and communities such as Khlong Chan flats, Ramklao flats, Athletes Village, and cooperative villages.

The complaint also points to a fundamental engineering misunderstanding by City Hall: proposing to replace monkey cheeks with canal widening and giant tunnels. Tunnels act like straws to convey water, while monkey cheeks act like containers to hold it. Without containers, the six existing giant tunnels cannot operate at full efficiency.

Moreover, the new draft reduces and eliminates floodways (green-striped zones) on both the east and west banks. The east bank is cut from the original 100,000 rai (240 sq km) to only 30,000 rai (50 sq km), despite being a low-lying tidal basin receiving runoff from Pathum Thani and Nakhon Nayok. The west bank (Thonburi side), which receives runoff from Nonthaburi, shows no floodway or green-striped area at all. If this plan is enacted without amendment, it will condemn Bangkok residents to unavoidable, repeated flood disasters.

Therefore, the Thai Sang Thai Party demands the Governor urgently review and amend the Comprehensive Plan (4th revision) as follows: 1. Adopt the royal initiative on monkey cheeks to survey and allocate maximum retention areas, or no less than 6 million cubic meters. 2. Strictly preserve floodways (green-striped zones) on both east and west banks. 3. Prohibit any land-use changes that facilitate real estate or commercial development in ways that obstruct water flow.