Longer water service interruptions as allocations reduced further

MANILA, Philippines — The National Water Resources Board (NWRB) has further reduced water allocation to the Metropolitan Waterworks and Sewerage System (MWSS)’s concessionaires after Angat Dam’s water level yesterday dropped below the critical 160-meter mark.

Dam information update provided by the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) showed that as of 6 a.m. yesterday, the dam’s water level was 159.78 meters or 0.5 meter less than Friday’s 160.28 meters.

NWRB executive director Sevillo David said the allocation for Metro Manila’s water concessionaires is now 36 cubic meters per second (CMS), 4 CMS less than the previous allocation of 40 CMS.

“So the 36 CMS allocation for Maynilad and Manila Water is now effective. At the same time, the Angat Dam Low Level Outlet (LLO) is now operational,” David added.

The NWRB said it has placed the dam on LLO mode, which involves opening the dam’s bottom channel.

“We have to monitor developments next week until July since it is expected that rains will come,” David said. “The decision if there will be further reduction in water allocation from the 36 CMS being implemented now will depend if there will be rains in the next couple of weeks.”

The insufficient rainfall over Angat watershed is compounded by the monsoon breaks, which PAGASA said is a shift between weather systems that results in short breaks to no rainfall for several days or weeks.

The 4 CMS reduction translates to a deficiency of 350 million liters per day equivalent to the daily water consumption of almost 700,000 people.

Manila Water said it is constrained to effect a new scheme of rotational water service interruptions for the entire east zone at an average of 12 to 17 hours per day.

“These are being implemented to equitably distribute the limited supply to all customers so that they will have at least several hours of water from their taps during the day to allow them to store water,” Manila Water corporate communications head Jeric Sevilla said.

Manila Water added that while the latest schedule of water service interruptions took effect yesterday, fine-tuning of operations may take around three days from reduction of supply to be able to achieve greater accuracy and reliability of published schedules, as the distribution of limited water supply needs to be balanced across the entire east zone.

The rotational water service interruption may be implemented until a sustainable safe water level in Angat Dam is achieved, Sevilla said.

He added that Manila Water will continue to provide regular updates regarding changes to the schedule of rotational water supply in the east zone.

The cut in water allocation is said to affect 80 percent of Manila Water’s customers in the east zone and 75 percent of the customer base of west zone concessionaire Maynilad.

The water in Angat Dam, which supplies 96 percent of Metro Manila’s tap water needs for its 12.8 million residents, comes from the watershed’s river basin that straddles the towns of Doña Remedios Trinidad, Norzagaray and San Jose Del Monte in Bulacan.

As this developed, senators are seeking an explanation from officials of the MWSS and the two concessionaires why they have failed to make sufficient preparations for the reduced water supply in Angat Dam.

Sen. Grace Poe, who led the inquiry into the recent water shortage in Metro Manila as chair of the public services committee, lamented that the water crisis appeared to have worsened despite lessons learned as well as assurances from the MWSS and its concessionaires Manila Water and Maynilad. – With Paolo Romero