TEMPO.CO, Jakarta - Head of Jakarta Development Planning Board (Bappeda), Andi Baso Mappapoleonro, said Jakarta is sinking at a rate of seven centimeters per year.

"Seventeen percent [of the sinking] is caused by the land extraction due to underground water exploration and 83 percent is caused by natural factors," Andi said at a seminar at Tarumanegara University, Jakarta, yesterday.

Jakarta residents may not feel the phenomenon but it happens very slowly, Andi added. In fact, it affects the activities in the city, such as drainage and flood mitigation. Worse, underground water that the residents consume has been contaminated with Coli bacteria.

Andi said that lands in Jakarta are alluvial lands, which will subside from year to year naturally. Besides, the development burden in the capital is already high.

"The environment in Jakarta can no longer support and accommodate development in the city," said Andi.

Subsidence is recorded in almost all parts of Jakarta, especially in the central part to the north, or from Semanggi to the north.

In the meantime, land extraction due to groundwater exploration mostly happens in coastal areas in North Jakarta, including Pluit, Grogol and Semanan. Land extraction also takes place in South Jakarta.

"We cannot control subsidence. So, Jakarta will be flooded for a long period of time," he said.

Andi said the Jakarta government has limited understanding of the situation. However, the city government has planned on constructing a sea wall expected to curb rising seal level and tides.

The Bappeda head also mentioned an alternative development moratorium, but later said: "However, can it be done to 12 million population?"

Another extreme measure, he said, is by relocating the capital.

ATMI PERTIWI