Global warming threatens Indonesia's groundwater supply: Expert

Erwida Maulia, The Jakarta Post 4 Dec 09;

Not only is global warming putting thousands of Indonesia’s islands at risk of sinking, it also threatens the country's groundwater supply, an expert says.

Heru Hendrayana, a hydrogeologist from Yogyakarta's Gadjah Mada University, said here Friday that groundwater volume in a number of regions has been proved to have reduced in the past few years, believed to be an impact of the warming earth.

"Global warming has led to climate change, which has immense influence upon the water cycle.

"It disrupts the wind and air pressure patterns and, in the end, causes changes in rainfall volume," Heru said after a discussion on drinking water in Jakarta.

He said although some regions enjoyed more rainfall due to the phenomenon, most suffered from less rain instead.

The reduced groundwater volume is evident in Yogyakarta and its surrounding areas, among others, he said.

Pollution is another threat for Indonesia's groundwater supply, especially in urban areas.

Heru said most groundwater supplies in metropolitan cities like Jakarta, Semarang and Surabaya were contaminated with E. coli bacteria because of poor sanitation, not to mention the vulnerability of groundwater to seawater intrusion.

The growing number of industries, gas stations, and carwashes in big cities has exacerbated the threat, said Heru, who is currently studying how far they have affected the groundwater supply.

To make matters worse, big cities, which are typically crowded with buildings, lack the capacity to absorb rainwater.

Heru said urban areas could only absorb 20 percent of rainwater, compared with 30 percent for suburban and 40 percent for rural areas.