Experts warn that by 2050, one-third of Bangkok will be permanently submerged. They urge the government to stop merely reviewing past lessons and instead accelerate proactive measures, pressing for reform of the national water plan. Sitangsuu declared that if Anutin does not change his mindset, we might have to change the country's leadership instead.
At 10:00 a.m. on 7 October 2026, the Thai Journalists Association held a seminar titled "Breaking the Cycle of Repeated Flooding: Thailand’s Long-Term Water Management Solutions" at the Best Western Hotel in Chatuchak. Experts and academics in water management participated, including Associate Professor Dr. Sitangsuu Pilailar, Water Resources Engineering, Kasetsart University; Associate Professor Dr. Seri Suparat, Director of the Climate Change and Disaster Center, Rangsit University, and Vice Chairman of the National Disaster Warning Council Foundation; and Dr. Sonthi Kotchawat, an environmental and health scholar.
Dr. Sonthi stated that the World Meteorological Organization (WMO), World Bank, and Greenpeace have warned that Bangkok has a high risk of flooding or submersion—between 40 and 96 percent—due to land subsidence of 1-2 centimeters annually caused by construction on soft soil, sea level rise in the Gulf of Thailand averaging 4 millimeters per year, combined with upstream rain-flood and the city’s basin-like shape. The city relies solely on pumping water, as seen at Wat Khun Samutthawat in Laem Fa Pha Subdistrict, Phra Samut Chedi District, Samut Prakan Province, where coastal erosion has left the temple standing one kilometer offshore.
Additionally, the World Health Organization (WHO) and Change Center have ranked Bangkok among six global cities most at risk of submersion and as the fourth most vulnerable to major floods worldwide, behind Jakarta, Mexico City, and Ho Chi Minh City. It is projected that by 2050, sea levels in the Gulf of Thailand will rise by 20-30 centimeters, potentially up to 75 centimeters, causing one-third of Bangkok’s area to be permanently submerged. Approximately 11 to 12 million residents may face displacement, with coastal areas like Bang Khun Thian, Samut Prakan, and Samut Sakhon the first to be affected.
For solutions, the government must urgently restore water catchment areas, build large underground drainage tunnels and retention basins, expand green spaces, plant mangroves, and use water-absorbing materials. Tax measures should be implemented, such as tax reductions for permeable land and taxes on properties fully covered with concrete. Urban planning must strictly prohibit residential construction in flood-prone areas. Groundwater pumping should be stopped to reduce land subsidence, and precise early warning systems using satellites, Big Data, and AI technology should notify local areas directly.
So far, Thailand has failed in four major flood events—from Chiang Rai, Chiang Mai, and Hat Yai to Bangkok. The government must cease simply reviewing past lessons and immediately reform water management structures. Currently, responsible agencies are scattered across ministries: the Office of National Water Resources (ONWR) under the Prime Minister’s Office, the Royal Irrigation Department under the Ministry of Agriculture and Cooperatives, the Geo-Informatics and Space Technology Development Agency (GISTDA) under another ministry, and the Department of Disaster Prevention and Mitigation under the Ministry of Interior.
By the time official documents cross agencies, it is often too late. We need to shift from reactive recovery measures to proactive ones with precision enabled by technology. A command center with cross-ministry authority must be established to act immediately. Decentralization of authority and budget to provincial governors and local governments is essential so they can prepare before disasters occur—not wait for disaster declarations and start emergency responses after people are already flooded.
Associate Professor Dr. Seri said it is time to revive and reform the national strategic and water management plans to be more flexible. He pointed out that although natural-based solutions have been included in plans, they have not been seriously implemented. Lessons from floods in places like Hat Yai and Nan, as well as current situations, must be urgently used to improve management structures.
The lessons from various areas clearly show the need for major structural reform. Meanwhile, flood early warning systems must delegate direct alert authority to local governments. If localities lack equipment, the government should support technology to prevent delays in warning. Importantly, media coverage should avoid recycling old information in headlines that cause public panic; instead, it should assess situations based on factual evidence.
He then addressed the situation in the Bang Pakong River basin, especially in Ban Sang District, Prachinburi Province; Chachoengsao Province; and Nakhon Nayok Province, which are facing severe flooding. Rainfall assessments estimate about 1.3 billion cubic meters of water over seven days, while the ONWR estimates 2.1 billion cubic meters. Averaging these gives about 1.7 billion cubic meters, nearly double the capacity of Pasak Chonlasit Dam. Water drainage into the Bang Pakong River is slow due to narrow, winding channels, shallow downstream areas, and high tides from sea level rise.
If relying on natural drainage, which averages a flow of about 640 cubic meters per second in October, it would take up to 30 days to clear the water. Therefore, use of pumps and water pushers must be accelerated. It is also proposed to consider diverting water through Rangsit Canal, Prawet Burirom Canal, and Saen Saep Canal to discharge into the Chao Phraya River if sufficient capacity exists. This is currently under joint evaluation with Bangkok Metropolitan Administration.
Associate Professor Dr. Sitangsuu noted that despite forecasts for years warning that 40-96 percent of Bangkok is at risk of submersion by 2030, as of 2026, Thailand has yet to seriously address the problem. Climate change is intensifying heavy rainfall and waterlogging patterns. The Meteorological Department provides broad data, but Bangkok and other provinces still lack the capacity to analyze localized rainfall data effectively.
“Bangkok once developed a model simulating 300 millimeters of rainfall like Hat Yai, but in reality, it was never used. Moreover, the city’s drainage system was designed for 60 millimeters per hour but now operates at only 60 percent efficiency, effectively handling about 40 millimeters per hour. When faced with accumulated waste and polluted water, even rainfall of 20-30 millimeters per hour causes flooding. Therefore, the public is advised not to move belongings to ground floors until mid-October has passed.”
Associate Professor Dr. Sitangsuu further stated that water management in the Chao Phraya River basin faces significant challenges, especially in managing water releases from the Chao Phraya Dam. Normally, water discharge is adjusted stepwise with 7-10 day intervals, but this time, sudden releases occurred due to large flood volumes in fields and communities before reaching water stations C2 in Nakhon Sawan Province and C13 at Chao Phraya Dam, leaving the Royal Irrigation Department only 1-2 days to manage.
Looking at the country’s integrated water management budget in the latest fiscal year, about 60.76 billion baht was allocated across five main programs: water supply, flood prevention, water source development, environment, and management. Over recent years, most of the budget has been spent on infrastructure under flood prevention and water source development, while management programs have received the smallest share.
It is proposed that the government shift investment from building infrastructure to developing decision-support systems that continuously integrate data using artificial intelligence without retirement limitations. Budgets should be allocated according to disaster risk areas. Most importantly, leaders and the country’s top officials must change their mindset. If leaders do not recognize their weaknesses or are unaware of what they do not know yet think they know everything, then if they do not change their thinking, we may have to change the leadership instead.