People's perception of land subsidence, floods, and their connection: A note based on recent surveys in a sinking coastal community in Jakarta

Land subsidence has triggered severe coastal floods in Jakarta, whose mechanism has been extensively investigated by researchers and engineers. The government has also recognized this fact, which has partially contributed to the recent announcement that the capital will be relocated to East Kalimantan. However, it is not clear whether ordinary people perceive the progress of land subsidence as their own issue. To ascertain this, a field survey was conducted after a major coastal flood that took place in December 2017, which revealed that nearly half of the people living in a rapidly sinking coastal community were not aware of the ongoing land subsidence under their own houses. Severe flood and land subsidence were not strongly recognized as interlinked problems by local citizens. Rain-induced flooding is common in the community, and this may explain why a quarter of respondents did not fear the 2017 coastal flood, despite their houses being flooded, in some cases to a depth above their heads. Land subsidence has an adverse effect on flooding. Awareness building programs for normal citizens should be promoted, in order to articulate the significance of stopping groundwater extraction for mitigating land subsidence and the flooding it induces.