Indonesia's economy has been spiraling downward for the past year. Now a worried geologist says its capital city is sinking as well, and that high-rise buildings may soon begin to lean and crack.

Hasanuddin Abidan of the Bandung Technology Institute said some areas in Jakarta had sunk more than 19 inches in the past several years because residents had been tapping too much underground water. Many of the coastal city's 10 million people use pumps and wells to supplement their daily water needs.River currents could shift and corrosive sea water could leach inland where it can damage the foundations of tall office towers and apartment buildings, Abidan told the Indonesian Observer newspaper Wednesday. Many of the structures were built during the boom days of the early 1990s but are now largely empty because of a year-long economic crisis.

Abidan said his research was based on satellite global positioning technology. It showed that some beaches in northern Jakarta had sunk 15 to 23 inches since 1994. Some inland areas had dropped up to 11 inches during the same period.

There was no immediate reaction to the claims by the government, which is grappling with its biggest economic and political shakeup in decades.

Jakarta sits on what had been swamp land on the northern coast of the main island, Java.