Angat nears lowest level in 14 years

MANILA, Philippines — Angat Dam in Norzagaray, Bulacan, the main source of potable water of Metro Manila residents, is close to breaking its lowest level record in 14 years, according to the Philippine Atmospheric, Geophysical and Astronomical Services Administration.

PAGASA hydrologist Sonia Serrano said as of 6 a.m. yesterday, the water level at Angat had dipped further to 158.40 meters.

The dam’s water supply hit its lowest at 157.56 meters on July 18, 2010, according to Serrano, citing data from 2006 to 2019.

“Angat needs 365 millimeters of rain to reach its normal operating level of 180 meters,” she said.

To reach the normal high water level of 210 meters, the dam needs 1,300 mm of rain.

PAGASA weather division chief Esperanza Cayanan said the enhancement of the southwest monsoon by Tropical Depression Dodong has so far not benefited Angat Dam.

Cayanan explained the heavy rains from the southwest monsoon were not reaching Norzagaray, which is located on the eastern side of Central Luzon, as the concentration of rains is in the western section.

Cayanan added that the brewing cyclone spotted east of Mindanao may dump more rains over Angat.

“We expect the developing weather disturbance to pass near Luzon area,” she said.

PAGASA said two to three cyclones are predicted to enter the country next month.

Cayanan had earlier said Angat could return to its normal level by July and August, when above normal rainfall is expected to prevail over Western Luzon.

The National Water Resources Board (NWRB) has reduced water allocation in Metro Manila and nearby areas as Angat breached its 160-meter critical level last week.

PAGASA deputy administrator Landrico Dalida Jr. has urged the public to collect rainwater to cope with the ongoing water interruptions.

Enough water but...

The NWRB assured the public that there is still enough water at Angat Dam but maintained that rotational water service interruptions must still be implemented to manage the supply until the full onset of the rainy season.

“We would like to tell the public that there is still water at Angat Dam. But we continue to implement water service interruptions in order for the supply to last until the rainy season... What we are doing is we are managing the supply,” NWRB Legal Unit head Archie Asuncion said in Filipino during his interview with “The chiefs” aired on Cignal TV’s One News last Tuesday night.

Asuncion said the Metropolitan Waterworks and Sewerage System (MWSS), together with its two concessionaires Manila Water Co. Inc. and Maynilad Water Services Inc., has already operationalized Angat Dam’s low-level outlet (LLO), the bottom channel of the dam, capable of releasing water below 160 meters.

Asuncion added that the LLO is ready to release supply once the water level at Angat Dam dips further.

As of Tuesday, NWRB executive director Sevillo David Jr. reported at the hearing at the House of Representatives that water level at Angat Dam was at 158.8 meters, or more than a meter below critical level.

“The LLO’s elevation is at 101 meters. Right now, the water level is at 158 meters. That means there is still enough water. But we need to manage it to even out the supply to all areas,” Asuncion said.

During the House hearing, David admitted that the daily water service interruption may last until August.

Meanwhile, NWRB Policy and Program Division chief Susan Abaño warned that the board may further reduce the water allocation of MWSS if water level at Angat Dam continues to decrease.

From 46 cubic meters per second, the NWRB reduced the water allocation of MWSS to 40 CMS and eventually to 36 CMS after the level at Angat Dam dipped below 160 meters.

Abaño, nonetheless, said the Board is planning to tap water from Marikina River, Laguna Lake, as well as other water sources from the provinces of Bulacan, Laguna and Cavite. – With Elizabeth Marcelo, Rhodina Villanueva