Overflow threat over as San Roque Dam stops water release

THE SAN ROQUE Dam in San Manuel, Pangasinan province, let out water to the Agno River at the height of heavy rain recently. ROGER TINGLE/Contributor

LINGAYEN, Pangasinan—The San Roque Dam in San Manuel town closed its spillway gates on Wednesday after noting that the flow of water from upstream Agno River had decreased, a dam official said on Thursday.

Valeriano Barro, flood operations manager of the National Power Corp., said the dam’s two spillway gates were closed at 1 p.m. on Wednesday after four days of spilling water into the lower Agno River.

Water inflow at 9 a.m. on Thursday was 294 cubic meters per second. A cubic meter of water is equivalent to 1,000 liters or about five drums of water.

Barro said water flowing into the San Roque Dam was coming from the Ambuklao and Binga dams in Benguet province that still have their spillway gates open.

At 6 a.m. on Thursday, water level at the Ambuklao Dam was 751.9 meters above sea level (masl), which was 10 centimeters from its spilling level of 752 masl.

Binga Dam’s water level was recorded at 574.47 masl, 53 cm from its spilling level of 575 masl. Two spillway gates in both dams were opened at a total height of 1.3 meters.

The water spilled by Ambuklao flows into Binga, whose spilled water is deposited at the San Roque Dam. San Roque Dam’s water level, as of 6 a.m. on Thursday, was 281.74 masl, which was 1.74 m above its normal high water level of 280 masl.

“With the spillway gates closed, the dam’s water level can now be lowered by the turbines of the San Roque Power Corp. (SRPC), which is still generating 411 megawatts of electricity for the Luzon grid,” said Barro.

SRPC, which only operates during peak hours, shifted into a “must run” status on Friday and started spilling water used by its turbines for power generation. On Wednesday, the Agno River Basin Flood Forecasting and Warning Center in Rosales town issued its final bulletin after observing that water levels in Pangasinan’s major rivers had receded and were no longer threats to riverside communities.

But the provincial disaster risk reduction and management office (PDRRMO) here said some villages along the Sinocalan, Marusay and Pantal rivers in the towns of Calasiao and Sta. Barbara and Dagupan City were still flooded.

Avenix Arenas, PDRRMO spokesperson, said the flooding in the province destroyed P700,000 worth of crops.

In Benguet, the remains of Marvin Batusi were recovered on Thursday by rescue volunteers, who had been scouring the creeks and eroded mountainside in Barangay Taneg in Mankayan town, said Insp. Joyce Ann Dayag, Benguet police spokesperson.

A section of the mountain toppled due to rains unleashed on Saturday by Typhoon “Ineng” (international name: Goni), with soil, rocks and trees falling on a camp set up by small-scale miners. At least 16 miners and their families were in the camp when the landslide hit.

Police are searching for 10 more people in the landslide area in Sitio Elizabeth. Batusi was the sixth miner to be retrieved since last week. Gabriel Cardinoza and Kimberlie Quitasol, Inquirer Northern Luzon