• Maia Rankine-Griffith & Annika Anandsongkit

A Sinking Feeling

Photo by Peerakit Jirachetthakun

When asked to name one of the world’s sinking cities, people often resort to California, Mexico City, Venice, the Mississippi Delta, Jakarta, Shanghai, and the Netherlands. Few people, however, acknowledge the threat Bangkokians are currently facing. A World Bank study predicts that 40% of Bangkok may be engulfed by waves as early as 2030. That is in less than 10 years. But why is this happening?

The Land Moves Down

Bangkok is becoming a victim of its own rapid development. As skyscrapers cover the city’s landscape, more weight is put on its shoulders. The “soft Bangkok Clay” that struggles to hold up the city is supple and weak. Surcharge loading takes place as roads, buildings, and bridges are built on every corner and Bangkok’s surface experiences a large magnitude of pressure.

With its vast work of canals, Bangkok is commonly referred to as the “Venice of the East”. Originally, these canals were high above sea level. However, many have been submerged below sea level. The city is sinking by one to two centimeters every year as the land is constantly burdened.

The Land Dries Out

While the weight of Bangkok’s towering skyscrapers bores down on its soft, mud underbelly, groundwater pumping from the aquifer system within it has been shown to exacerbate subsidence rates. In fact, deep well pumping has been affecting the city for the past four decades, the impacts of which are only now beginning to be felt by the average citizen.

Data Visualization by Maia Rankine-Griffith

For every 1 cubic meter of groundwater pumped out, approximately a tenth of a cubic meter of ground loss will occur at the surface.

Despite strict mitigation measures having been implemented, including the rigorous enforcement of groundwater laws and pricing policies, it is not a secret that drops in groundwater use will not reverse the damage done. Bangkok is a modern, buzzing metropolis of close to 11 million inhabitants. It is a city that is growing and becoming more crowded every day. When accommodating for these incessant surges in population growth, the significance critical, gradually emerging issues such as this one often go overlooked. However, very rarely do these issues surpass the point of no return, where the largest, long-term consequences of its presence no longer are avoidable.

With groundwater being extracted still to this day, it is undeniable that Bangkok is nearing this point, with no indication of any major efforts to stop this from happening.

The Sea Moves In

Bangkok is beginning to drown as the impacts of climate change have further aggravated the situation. Temperatures continue to rise and the survival of Bangkok is at stake.

The loy-lying city precariously sits on the Chao Phraya River delta with an average elevation of 1.5 meters above sea level and is more vulnerable to frequent flooding events. This can be accounted for by the thermal expansion of water as a result of global warming. As temperature escalates, water molecules expand and increase the total volume of water causing sea levels to rise. This will alone reach up to 2 meters and inundate most of the city. Uncontrollable floods will put people’s lives at risk and infrastructure in danger, incurring high costs for the city.

Tara Buakamsri, campaign manager for Greenpeace Southeast Asia, warned that “Bangkok has been identified as one of the climate change hot spots – it will be one of the most affected cities in the world... Climate change and its effect needs to be on the national agenda and made a central part of Thailand’s development plans – it cannot be seen as a stand-alone issue.”

Bangkok is struggling to stay afloat. If the government does not act now, Bangkok will be underwater, unable to breathe.

Photo by Karl Grenet

It is a common misconception that subsidence will come to a halt once all of these activities cease. In reality, they served merely as triggers to the long-term sinking of the land, due to the time-dependent consolidation of the soft clay layers that lie beneath the city. In other words, once it starts, every passing second renders it more difficult to solve.

Yet, not unlike most environmental issues, this one is far from being out of our control.