Government expects Metro Manila’s main water source Angat Dam to still serve, until the third week of this month, its domestic, irrigation and power purposes despite the drought and dry spell prevailing in the country.
“Water in Angat can still supply till then water for suchpurposes,” said hydrologist Elmer Caringal from government’s weather agency Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).
He urged water conservation, however, expecting Angat’s water level to afterwards reach 180 meters around the latter part of May.
National Water Resources Board (NWRB) refers to such point as Angat’s minimum operating water level.
“It’s also the level at which NWRB can begin reducing Angat’s water supply for irrigation,” Caringal said.
He noted such reduction aims to ensure availability of water for Metro Manila’s domestic needs.
NWRB is government’s lead agency in the Philippine water sector.
Conferred with policy-making, regulatory and quasi-judicial functions, NWRB is responsible for ensuring optimum exploitation, utilization, development, conservation and protection of the country’s water resources consistent with integrated water resource management principles.
In its monitoring report released Tuesday (May 5), PAGASA said Angat’s reservoir water level already dipped to 186.01 meters as of 6 a.m.
PAGASA reported Angat’s 6 a.m. water level at 186.90 meters on Saturday (May 2), marking a 0.29-meter decrease from 187.19 meters 24 hours earlier on Friday (May 1).
Such dip approximates data on Angat’s water levels.
“The data show water level in Angat lowers by some 0.28 meters daily during the dry season,” said Caringal.
Rule curve for Angat decreases 0.11 meters daily, he also said.
“If both happen, Angat’s water level will be at 180 meters later this May,” he said.
Rule curve is the desired water level to satisfy Angat’s purposes.
NWRB earlier set daily rule curves to control withdrawal of Angat’s water so this commodity can still be available for supply to Metro Manila, noted PAGASA.
PAGASA forecast weak El Nino to prevail until mid-2015.
Drought-driving El Nino is characterized by unusually warm ocean surface temperatures in the central and eastern equatorial Pacific, PAGASA said.
Last week, the weather bureau said its assessment as of April 23 this year shows drought and the dry spell already affected 54 provinces nationwide.
PAGASA’s outlook for May 2015 shows four other provinces — Camarines Norte, Catanduanes, Quezon and Romblon — will likely experience either drought or the dry spell this month.
Earlier, senior PAGASA hydrologist Max Peralta said the prevailing weak El Nino phenomenon won’t significantly affect availability of water in Angat Dam.
He noted Angat has enough water to meet Metro Manila’s needs until May when the dry season in this megalopolis normally ends and the wet season here begins.
Peralta also expects precipitation in the Angat area, saying the rain-driven southwest monsoon or “habagat” will prevail in the country by then.
Like Caringal, however, he continues urging the public to conserve water.