Despite water supply restrictions imposed by the government on Metro Manila, Angat Dam in Norzagaray, Bulacan hits its all-time low water level Sunday at 158.18 meters.

The water level in the reservoir is already 11 centimeters below the previous lowest level, thus far, in Angat Dam’s history of 158.29 meters recorded on Sept. 13, 1998.

As of 6 a.m. Sunday, Angat Dam’s level had a deficit of 23.11 meters from its normal operating level.

Angat Dam, which has been operating under a 180-meter critical level since April, recorded a 20-centimeter daily water decrease since June, relatively slower than the 50-centimeter rate of water decline in April and May.

Authorities said rains over the watershed were insufficient to replenish water in the reservoir.

The National Water Resources Board (NWRB), the lead government agency that regulates the country’s water supply under the Department of Environment and Natural Resources (DENR), implemented a cut on Metro Manila’s water allocation last Saturday to meet the water demands of at least 12 million consumers until the water level in Angat Dam will have normalized.

About 97 percent of Metro Manila’s domestic water requirements are sourced from Angat Dam.
In an interview, Engr. Jorge Estioko, chief water resources development officer of the NWRB, said only 20 percent of the normal water inflow into the reservoir has been recorded in the past weeks.

The present allocation for domestic water supply in Metro Manila of 32 cubic meters per second (CMS) or 2,784 million liters per day (MLD) is about 30 percent lower from the normal allocation of 46 CMS or 4,000 MLD.

The water allocation of 32 CMS is split 60-40 with the higher share for west zone concessionaire Maynilad Water Services Inc. (MWSI).

Estioko said Maynilad and Manila Water Company Inc. (MWCI) consumers will likely experience lower water pressure or shortened hours of water service due to the cut in water allocation.

He pointed out that seven million consumers in the west zone will bear more of the impact of lower water supply than the five million consumers of east zone concessionaire Manila Water.

This is due to the bigger recorded percentage of water losses from leaks incurred by Maynilad as translated in its non-revenue water (NRW) with 53 percent, as against Manila Water's NRW of 20 percent.

“Before the water requirements of consumers reach them, millions of liters of potable water could have been wasted because of leaks in pipes," Estioko said.

The west zone concession covers nine cities and two municipalities in Metro Manila and one city and five towns in Cavite province.

These are the cities of Pasay, Caloocan, Las Piñas, Parañaque, Valenzuela, Muntinlupa, Manila except portions of San Andres and Sta. Ana, some parts of Makati and Quezon City, and the towns of Malabon and Navotas, all in Metro Manila.

Meanwhile, areas in Cavite province under the Maynilad are Cavite City and the towns of Rosario, Imus, Noveleta, Bacoor, and Kawit.

Manila Water provides water services to the east zone of the metropolis that covers Makati, Pasig, Mandaluyong, Marikina, most parts of Quezon City, some parts of Manila, San Juan, Taguig and Pateros.

At present, Angat Dam supplies domestic water to Metro Manila using a low-level water outlet, which is capable of operating below a 160-meter water level, going directly to Bulacan’s Ipo Dam and further down to La Mesa Dam in Quezon City.

This is due to the suspension the operations of the Angat Dam’s turbines for repair and maintenance last July 7.

Estioko explained that the Angat Plant management may further defer the operation of Angat Dam’s turbines to prevent the machine from breaking down because the efficient level for the turbine to operate should be more than 160 meters.

Earlier, DENR Secretary Ramon Paje issued a statement assuring the public that there is no water crisis yet.

He said water supply remains “manageable” to meet the domestic requirements of Metro Manila’s residents.

The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) noted that during the 1997-1998 El Niño, Metro Manila’s water supply was reduced from 37 CMS to 22 CMS, resulting to water rationing.

Meanwhile, the distribution of available water was reduced to four hours per day.

It said that about 30 percent of the population of Metro Manila who have no access to water coming from the Metropolitan Waterworks and Sewerage System (MWSS) relied on private operators, which offered water at a higher cost.

The NWRB is currently conducting weekly monitoring of Angat Dam to determine if further water allocation adjustment is needed.