Jakarta sinking as fast as 10cm per year

Irawaty Wardany, The Jakarta Post 24 Apr 10;

Jakarta, the nation’s capital and largest city, is sinking at a rate of 10 centimeters a year, a recent study has found.

The main causes for this phenomenon, which has been evidenced in recent years by several major floods, are extensive land extraction due to groundwater exploration and pressure from high-rise buildings, which is pushing parts of the city into the underlying water table.

“The land has been sinking for a long time, and the coastline is now encroaching on the heart of the city,” a geodynamics researcher from the Bandung Institute of Technology Irwan Gumilar told The Jakarta Post.

Irwan was a member of a research team led by Professor Hasanuddin Z Abidin that monitored Jakarta from 1997-2009.

“Few people may realize that the land is sinking by 10 centimeters to 12 centimeters a year,” Irwan said.

The highest rate of subsidence was recorded in coastal areas in North Jakarta, including Muara Kapuk and Ancol, where extensive development had increased pressure on the relatively young and porous soil beneath.