Jakarta lies on soft layers of sand and clay. If you pump out more groundwater than naturally flows in, the water pressure will decrease and the clay layers in particular will collapse. Large parts of Jakarta have thus fallen below sea level.
The city is a bathtub. Rivers run through it, but they can no longer discharge their own water into the sea because the sea level is too high. So the water has to be pumped out. Not the sea, but the city is now the drain, which entails enormous pollution.
In 2019, the Indonesian government decided to build a new capital on the island of Kalimantan. Life in Jakarta had become too unsafe because of the rising water. So, this decision is a BIG sign for people to move out of Jakarta. But, as you know ... people are ... like ostriches, sticking their heads in the sand. Don't want to deal with the emerging danger.
26% of Netherlands is bellow the sea level.Jakarta is sinking because people there have few options but to use groundwater. On top of this, seawater is now polluting the groundwater, adding to people's misery.p.dw.com