Bangkok is not Venice, but will our future be the same?

This demand is more or less influenced by news from a few years ago claiming Bangkok would be inundated by floodwaters in the next decade. Will this inundation of Bangkok really happen so soon? 

In a nation in which more than half the population searches for signs of winning lottery numbers in five-legged buffaloes, two-headed turtles and other strange phenomena, the “Bangkok inundation” myth squarely hits the public’s panic glands. Insufficient scientific awareness contributes to the rate at which misunderstandings become accepted as facts. Even academics become its victims.

Bangkok as the Venice of the East is frequently referenced in textbooks and research papers. The comparisons stem from the numerous waterways that criss-cross both cities. While both cities have waterways, this comparison is inaccurate. In tracing historical records of early European visitors to the region, we find that it was not Bangkok but Ayutthaya that was compared to Venice. Moreover, there were significantly more waterways in Ayutthaya, or even Bangkok, than there were in Venice. The only comparison that has integrity is the similarity of Ayutthaya and Venice’s standing as prosperous trading centres and thresholds between the worlds of the East and West – and that is surely not enough as a foundation for the likelihood of inundation.

Another misinterpretation is also grounded in ignorance of science. It is widely believed that, due to global warming, Bangkok will be under sea level in the very near future. Part of Bangkok’s coastline has been eroded by more than 1 kilometre in a decade. With such high rates of erosion, it becomes feasible that Bangkok will be totally under sea level in only a few decades. Fortunately, this may not be the case.

Topographical analysis of 100-year old maps and the present Royal Thai Survey Map of the Delta show patterns of coastline erosion and reestablishment – and, more importantly, greater proportions of reestablishment than erosion – in the Gulf of Thailand. Since the 1970s, there has been scientific consensus that the present Chao Phraya lower delta area was transformed from the seabed of the Gulf of Thailand a few thousand years after the last glacial period. Data supports the observation that Bangkok land over sea level keeps increasing, not decreasing. 

Unfortunately, human intervention alters this situation. Even if an inundation were not directly influenced by seafront corrosion, which is mainly caused by the widespread destruction of mangrove areas, another contributing factor would be ground sinkage.

Long-term over-usage of ground water by the industrial sector was the first trigger and was accelerated subsequently by the drastic reduction of natural water-infiltration areas which became colonised by the primary features of an expanding urbanisation: impermeable asphalt surfaces and concrete construction. Let us imagine what would happen if 1500 km2 of concrete plate was laid on muddy delta soil. Yes: it would sink. It is the responsibility of engineers and architects to understand the nature of deltaic topography, and to make sure that more opportunities to preserve our city are not missed. 

The interpretation of Bangkok as the Venice of the East is a misleading historical inaccuracy. But misinterpreting the threat of Bangkok’s inundation in the age of global warming is dangerous. It blinds us to the real conditions that challenge our future and leads us away from constructive action. 

 

Writer: Asst Prof Terdsak Tachakitkachorn PhD, Dept of Architecture, Faculty of Architecture, Chulalongkorn University