What environmental issue is Bangkok facing due to heavy demands on groundwater?

Bangkok is facing significant challenges related to groundwater extraction, particularly the phenomenon of sinking. The city's heavy reliance on groundwater for various uses, including agriculture, industry, and domestic consumption, has led to severe water depletion. As groundwater levels drop, the land above it can become unstable, resulting in subsidence or sinking of the ground. This condition has been particularly alarming in Bangkok, where urban development and population growth have intensified these pressures. High rates of subsidence can lead to structural damage, increased flooding risk, and other urban planning challenges.

In contrast, while flooding, air pollution, and deforestation are relevant environmental concerns for Bangkok, they do not directly stem from groundwater extraction to the same extent as sinking does. Flooding may be exacerbated by urbanization and poor drainage systems, air pollution is heavily influenced by vehicle emissions and industrial activities, and deforestation can be linked to land use changes. However, the immediate environmental consequence of heavy groundwater extraction is the ground’s subsidence, making sinking the most fitting answer.