Overview
- The UN’s World Urbanization Prospects 2025 names Jakarta the biggest metropolitan area at about 42 million people, surpassing Tokyo based on real growth and updated methods.
- UN DESA links the ground sinking to excessive groundwater extraction, the weight of urban infrastructure and natural sediment compaction, with many northern areas already below sea level.
- Reported rates differ by source and neighborhood, with official averages near 7.5 cm a year and localized declines of 17–30 cm annually that jeopardize homes and critical infrastructure.
- Sea-level rise and increasingly intense rainfall are compounding subsidence, driving more frequent and severe flooding across the low-lying city.
- Officials are developing a Giant Sea Wall, restoring rivers, expanding public transport and pursuing a phased move of some state functions to Nusantara, steps that can limit flooding but cannot stop the sinking.