Pagasa gets tips from Japanese experts on timely release of dam water

MANILA, Philippines—It’s “dam if you do, dam if you don’t.”

The extreme weather has put dam operators in a bind. If they release too much water, communities downstream would be inundated; if too little, the dams may break.

But there’s a way to “control” flooding by applying more science to the country’s flood forecasting and warning systems, especially around Luzon’s six major dams, according to the weather bureau.

The Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) on Tuesday completed a Japan International Cooperation Agency-funded seminar with stakeholders from the power and irrigation sectors aimed at improving their technical capabilities.

Pagasa, National Power Corp. (Napocor) and the National Irrigation Administration (NIA) also pledged to collaborate more closely, especially in exchanging information during extreme weather events.

At a seminar held at the Edsa Shangri-La hotel, Koichi Takano, an engineer at the Japan Water Agency, talked about how to mitigate problems arising from the extreme weather and the resulting floods.

He said there was no “one size fits all solution,” but the Japan Water Agency showed how effective flood control could be achieved through integrated dam operations.

Pagasa Administrator Nathaniel Servando said Pagasa scientists earlier went to Japan to improve their flood-forecasting and warning-systems skills, including hydrological modeling, so that “when it rains, they [will] have numerical simulations to determine when the waters will rise.”

“The Napocor is involved because dams are for power generation, and the NIA for irrigation. It will help, especially during flood events, so the dam [operators] will know when to release water and when not to,” he said.

Servando said the focus was also on capacity development for the technical staff. “There will be equipment, such as water sensors and rain gauges, installed in the catchment areas of the dams in major river basins in Luzon,” he said.

He also said “there is a closer collaboration with stakeholders, including the communities and local government units, who need to be alert during extreme events and monitor all the warnings from agencies like Pagasa. The NPC and NIA also give out information.”

The JICA-funded flood project, mostly on technical cooperation, will be completed by November.

Servando said the dam releases impacted flooding according to area.

“For example, in the Pampanga river basin, there are two dams, Angat and Pantabangan. The flooding in the downstream community, like Bulacan for example, if you look at the area Pantabangan has a greater contribution (to the flooding) than Angat,” he said.

Servando said the ideal system would be where the dams could release some water even before the rains fall.

“You control the water. You try to prevent the flood, so the release of water is not so sudden,” he said.