MANILA, Philippines — A huge portion of Metro Manila and nearby provinces should expect service interruptions until this weekend after the National Water Resources Board (NWRB) decided to further cut allocation amid the continued drop in the water level at Angat Dam, the metro’s main water source.
The NWRB is reducing the allocation for Metropolitan Waterworks and Sewerage System (MWSS) to 40 cubic meters per second (CMS) from the current 46 CMS starting today until this weekend.
The NWRB meanwhile is fine-tuning preparation of the low-level outlet as a back-up water discharge before the Angat Dam level reaches 160 meters and lessen the significant effect of limited water supply in the coming days.
With the cut in allocation, 70 percent of the customer base of west zone concessionaire Maynilad Water Services Inc. will be affected while 80 percent of east zone Manila Water Co. Inc. will be hit.
Angat Dam’s water level dropped further to 161.78 meters yesterday and is expected to hit critical level this weekend.
As of 6 a.m. yesterday, the water supply of Angat Dam, which supplies 97 percent of Metro Manila’s water demands, was 18.22 meters below its normal operating level of 180 meters.
MWSS administrator Reynaldo Velasco said Angat Dam’s water level would dip to a low-level mark of 160 meters if it will not rain by June 20.
“If the (monsoon break) forecast of PAGASA continues, we would reach 154 meters by end of June,” Velasco said, referring to the Philippine Atmospheric, Geophysical and Astronomical Services Administration, in an interview with radio station dzMM.
“This will affect water supply going to our treatment plants and consequently, our ability to refill our reservoirs. We are therefore constrained to implement a new scheme of rotational water service interruptions for the entire east zone for about eight to 12 hours during nighttime,” Manila Water spokeman Jeric Sevilla said.
“Of the 70 percent, 20 percent will be severely affected, where only eight hours will be the supply window. The remaining 50 percent, they have roughly nine to 16 hours of water supply,” Maynilad Water Supply Operations head Ronaldo Padua said.
Maynilad said it has mitigating measures in place, including the extension of the operating hours of pumping stations and the reactivation of deep wells. It will also deploy mobile water tankers and install static water tanks for severely affected areas.
Further, NWRB executive director Sevillo David Jr. said another adjustment will be undertaken on Saturday or once the 160-meter level is breached because the auxiliary unit will be shut down.
“However, it is assured that at least 36 CMS will be allocated to MWSS until the dam further declines to 150 meters, assuming that there is no significant inflow,” David added.
While there were intermittent rains in the past few days, the NWRB said these have not significantly improved the water elevation in Angat Dam.
“It continuously declines despite the PAGASA pronouncement of the onset of rainy season. A monsoon break is present in the country which lessens the chance of rainfall in the coming days. Earliest downpour is expected in the last week of June,” David said.
The NWRB is urging the public to conserve water to reduce the water demand from Angat Dam to prevent the rapid decline of water level and contribute to its recovery. – With Helen Flores, Rhodina Villanueva