City urged to cancel plan to divert upstream rivers

JAKARTA (JP): The government was urged on Tuesday to cancel its plan to alter the courses of upstream rivers into the Cisadane River, which flows to Tangerang.

Speaking before city councilors in charge of development affairs, city mining agency head Ali Rozi said it was a deplorable idea that would cause water shortages in the capital.

"It's more important to preserve surface water by constructing more dams to retain water in the city. This will prevent both flooding and droughts," he told the councilors.

"Shifting the flow of the upstream rivers that run into the city will cause droughts because there will be no surface water available in the city during the dry season," he said.

Surface water, he said, is available up until a depth of approximately 20 meters. While underground water is found between two hard rock layers some 250 meters below the surface, he added.

Ali said the central government's idea would initially be carried out by the State Ministry of Public Works.

During the meeting, he also said the city badly needed a water management system to anticipate the increasing demand for fresh water for its some 10 million residents and the vast number of business users.

"The system should integrate flood control and water supply systems," he said without elaborating further.

He said that constructing more artesian wells to absorb water would help preserve surface water which, in turn, would also preserve underground water reserves.

"The wells will absorb water during the rainy season, which residents can then use during dry season. This way we can preserve our underground water reserves," he said.

Ali explained that the city annually consumes between 12 and 15 million cubic meters of underground water from the available reserves of 77 million cubic meters.

"However, it doesn't mean that we can exploit the resource at our disposal."

He said there were a total of 3,102 deep wells in the city already registered at the agency that, last year, generated some Rp 30 billion (US$3.95 million) of revenue.

"We hope to earn some Rp 34 billion in the 1999/2000 fiscal year and Rp 29 billion in the 2000 fiscal year," he added.

Ali denied allegations that the exploitation of underground water had led to significant land subsidence in the city.

"Underground water is found between two hard rock formations, so the exploitation of it is unlikely to cause drops in ground surface levels here," he said. (05)