MANILA — The water level at Metro Manila’s main water source, Angat Dam, might dip to a new record-low level by yearend, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said in its forecast.
The weather bureau has warned metropolitans to conserve water, amid the possible return of drought-driving El Nino phenomenon, based on expected rainfall level in the dam in December.
PAGASA hydrologist Richard Orendain said this week Angat Dam’s water level by Dec. 31, 2018 might be at 191.50 meters.
“That’s even below 203.30 meters, the lowest year-end water level of Angat during the 2005-2017 period and which occurred in 2010,” Orendain noted.
He added that the forecast is also below Angat’s year-end 207.30-meter rule curve, which the government has set as water level guide for ensuring the dam has enough reserve for irrigation, power, and Metro Manila’s water needs.
Orendain, thus, advised users of Angat Dam water to start saving water now, even just by fixing leaking pipes at home, so the dam can still provide them water until early next year even at less volumes.
Citing latest data, Orendain said the shift to El Nino state is highly likely anytime from October to December this year.
Among El Nino’s impacts on the country are rainfall shortage and drier-than-normal conditions.
The expected year-end water level at Angat Dam for 2018 is far from normal, Jayson Bausa, another PAGASA hydrologist, also noted.
“Water level there usually surpasses the 200-meter mark,” he said.
PAGASA came up with its year-end forecast for Angat Dam, as it expects about 156 millimeters (mm) of rainfall coming to the basin of the facility in December.
“It’s less rain compared with previous years, when rainfall there normally reached 250 mm to 300 mm,” Orendain said.
He said the December 2018 rainfall forecast might indicate a possible return of El Nino.
In assessing Angat’s year-end water level, PAGASA also considered the 66 cubic meter per second (cms) allocation that the National Water Resources Board had set for the dam this December.
“Such allocation is normal for Angat,” Orendain said, adding the allocation consists of 20 cms for irrigation and 46 cms for Metro Manila.
Angat’s water passes through turbines for power production before being channeled towards Metro Manila and several irrigation areas in Central Luzon.
According to PAGASA, Angat Dam’s 6 a.m. water level on Friday (Nov. 30) was at the 202.33-meter mark.
Such level was 0.07 meters lower than the 202.40-meter water level there 24 hours earlier, the weather bureau said.