Binga, Ambuklao dams in Benguet open spillway gates as strong rain pounds northern Luzon

DAGUPAN CITY — The Ambuklao and Binga hydroelectric dams in Benguet province have begun spilling water into the Agno River, as strong rain pummelled northern Luzon, the government weather bureau said on Saturday (July 21).

Two spillway gates were opened at the Ambuklao Dam at 6 a.m. on July 20 (Friday). Its operators opened a third gate at 12 a.m. Saturday (July 21) when the dam’s water elevation rose to 749.8 meters above sea level (masl), or just 2.2 meters below its normal high water level of 752 masl.

The Binga Dam also raised five spillway gates at 12 a.m. on Saturday, according to the website of the Philippine Atmospheric Geophysical and Astronomical Services Administration (Pagasa).

The dam’s water elevation was recorded at 572.64 masl, which is 2.36 meters below its normal high water level of 575 masl.

A dam official said a spillway gate opened by half meter releases water at the rate of 65 cubic meters per second. A cubic meter of water is about 1,000 liters or about five drums of water.

Water released by the Ambuklao is collected at the Binga dam below, while the water spilled by Binga is caught by the San Roque Dam, which is the downstream of the Agno River in San Manuel town in Pangasinan province.

At 12 a.m. Saturday, the water level at the San Roque dam reservoir was 255.99 masl, which is 24.01 meters below its high level of 280 masl. The dam can accommodate water up to 290 masl.