E

xperts said Monday the city administration should prioritize the development of structures to improve groundwater absorption.

"The city administration places high priority on preventing floods by building canals but it only allocates a small amount to groundwater absorption initiatives such as making biopore holes, absorption wells, conserving lakes and greenbelt areas," Nila Ardhianie said, the director of Amrta Institute, an NGO that aims to raise public awareness on water-related issues.

According to the institute's data, this year Jakarta allocated Rp 750 billion (US$78,000) to establish the East Flood Canal, while only Rp 9.4 billion is allocated to the Jakarta Environmental Management Agency (BPLHD)

The agency manages groundwater absorption and supervises city environmental regulations.

Nila said by developing these initiatives, the city administration could achieve three aims: preserve groundwater, prevent land subsidence and prevent floods.

Currently, the ground in Jakarta absorbs less water than the amount it should, decreasing its groundwater level.

The BPLHD reported that the city lost 65.8 million cubic meters of its groundwater annually.

The decline of groundwater also causes land subsidence.

However implementing absorption methods can help the city recover its groundwater.

Floods can be prevented by increasing the absorption of rainwater.

Nirwono Yoga, the coordinator of Green Map Jakarta, agreed.

He said the city sewerage system could potentially advance groundwater depletion if it was not effectively managed.

"The city administration must change its way of thinking," he said.

"The sewerage pipes carry water into the sea and rivers and prevent water absorption and the recovery of groundwater.

"The sewerage system is prone to fail," he added.

"The system passes through many ditches and most of them are being blocked by trash."

Nirwono said currently the low level of groundwater absorption meant the water condition in Jakarta was far from ideal.

According to Nirwono, Jakarta's greenbelts should constitute 21 percent of the city but currently they only constitute about 9 percent (about 6,500 hectares).

He added between eight and 15 small lakes in the city are also in bad condition.

Despite a 2005 gubernatorial regulation that each building in Jakarta must have an absorption well, only 50,000 buildings in Jakarta have them.

Dian Wiwekowati, the BPLHD city resource management chief, acknowledged the budget allocated for groundwater absorption was too small.

"The BPLHD is focusing on encouraging the public to build their own biopore holes and absorption wells," she said.

She added the BPLHD could not do much about small lakes and greenbelts, which were managed by other agencies.

"However, we do recommend the agencies preserve the small lakes and green areas.

"Also, the city administration has been trying to increase the city's reserves," she said. Dian also added canals did not always prevent water absorption.

"It's true that canals can prevent water absorption if they are properly cemented.