Jakarta – Imbalances between development and environmental conservation in Jakarta may lead to several major floods in the city in coming years, a hydrology expert said.

Climate change is also increasing the likelihood of floods occurring in the capital, Firdaus Ali from the Regulatory Body for Jakarta's Water Supply said Thursday.

"The five- or 10-year cycle of flooding has become obsolete and it is possible Jakarta will be hit by massive floods twice in the same year," he said during a public discussion on water drainage solutions.

Firdaus said an increase in the number of natural disasters occurring around the world was a cause for concern. "Storms in all parts of the world became... worse during the last 10 years. Just look at Bangladesh which was hit by cyclone Sidr. We should be preparing for these types of things."

Cyclone Sidr generated winds of up to 250 kph and caused a five-meter tidal surge in Bangladesh last month. It killed more than 2,500 people.

Firdaus said recent instances of flooding in Muara Baru, North Jakarta, were a sign of things to come in the capital. Data from the Public Works Agency indicates that floodwaters reached 2.2 meters when high tides inundated several North Jakarta coastal regions recently. In the past, water levels rarely exceeded 1.6 meters during such floods.

I Gde Nyoman Soewandhi, the head of the water and coastal resources management unit at the Public Works Agency, said city planning was sometimes in conflict with environmental planning as new buildings were reducing green areas in the city.

"It would be ideal if we could continue on with development without changing water run-off levels, but that would be impossible," he said, adding that the city's current drainage systems were inadequate to mitigate flooding.

Firdaus said the administration should construct a multi-purpose deep tunnel network which would serve as a drainage system during the rainy reason and a traffic route during the dry season.

"The project can't be delayed as I doubt the flooding cycle is still the same as it was in previous years. I hope I am wrong, but I highly doubt it," he said.

Meanwhile, the Jakarta Flood Project, which studies all aspects of flooding in Jakarta in cooperation with the Public Works Agency, has predicted more floods caused by high tides will occur on Dec. 23 and 24.

"Climate change only plays a minor part in this. The current high tides are part of an 18.6 year lunar cycle which has been worsened by land subsidence," project executive Jan Jaap Brinkman from Delft Hydraulics said.

The team predicted several floods would be caused by high tides this year, including a flood on Nov. 26 that isolated Soekarno Hatta International Airport for hours. (anw)