Three Luzon Dams Under Close Watch as Water Levels Decline

Aside from Angat Dam in Bulacan, which supplies more than 90 percent of potable water to Metro Manila households, state meteorologists are closely monitoring the situation in three other reservoirs in Luzon, whose water levels have also been declining. Reserved water in Pantabangan Dam in Nueva Ecija fell to 175.97 meters yesterday, or below its normal level of 216 meters, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA). In Isabela, the elevation in Magat Dam has dropped to 161.05 meters. Magat’s normal water level is 190 meters. San Roque Dam in Pangasinan yesterday logged an elevation of 226.83 from the usual 280 meters. PAGASA climate monitoring and prediction chief Ana Liza Solis said these three reservoirs have been classified as “monitored dams,” meaning the water levels are being regularly monitored by the hydrology division. The water level in Angat, which supplies more than 90 percent of potable water to Metro Manila households, further dipped to 150.91 meters yesterday. Solis warned that due to continued consumption, the water level in Angat will continue to decline even as scattered rains have been occurring. One option that members of a technical working group (TWG) formed to study measures to raise the water level in Angat is cloud-seeding. The TWG is composed of the PAGASA, the National Water Resources Board, the National Irrigation Administration and the National Power Corp. as well as water concessionaires Maynilad and Manila Water. Solis warned that with lower rainfall expected in the months ahead, Angat Dam may struggle to recover its elevation before the dry season starts next year. “What we’re only hoping after the habagat season is that the amihan will be strong enough to bring more rain and improve the water level in Angat Dam,” she said, referring to the northeast monsoon. Authorities said that most dams in November will experience way-below-normal rainfall, with Angat projected to receive just 29.7 millimeters of rain, Pantabangan 71.4, Magat 77.2 and San Roque 45.2 mm. This could affect water supply for key agricultural areas and urban centers in the Philippines.