EXPLAINER: What happens when Angat Dam hits 'critical' level?

The water level at Angat Dam continues to drop as sparse rainfall fails to replenish its reserves, according to Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA).

The dam supplies more than 90% of Metro Manila’s water needs, serving at least 14 million people in the National Capital Region.

Beyond domestic use, Angat Dam also provides irrigation for about 28,000 hectares of farmland in Bulacan and Pampanga.

It also generates 200 megawatts of electricity for the Luzon grid.

What do the dam’s water levels indicate?

The normal high water level of Angat Dam is 210 meters above sea level, while its minimum operating level is 180 meters.

Once the dam falls below its minimum operating level, water releases for irrigation are reduced or temporarily suspended, potentially causing service interruptions in some areas. Power generation is also halted, reducing reserve capacity in the Luzon grid.

The critical water level, meanwhile, is set at 160 meters above sea level.

If the dam drops below this threshold, irrigation supply may be fully suspended, while water allocations to Manila Water and Maynilad Water Services may be cut, leading to rotational interruptions and water rationing in affected areas.

As of 8 a.m. on June 25, 2026, the water level at Angat Dam was recorded at 162.94 meters—just under three meters above the critical level—and still declining, according to PAGASA.

What happens if it falls below critical?

This would not be the first time the dam has breached critical levels, and past incidents have shown how severe the impact can be.

At the height of a strong El Niño–Southern Oscillation on July 18, 2010, Angat Dam hit its lowest recorded level at 157.56 meters above sea level.

Nearly 3 million customers of Maynilad Water Services were affected, with supply completely cut in 32 barangays. Residents endured long lines at fire trucks and water tankers for nearly a month until the rains replenished the dam in September.

The dam again breached its critical level on June 23, 2019, dropping to 159.43 meters amid another El Niño–Southern Oscillation.

That came just months after one of Metro Manila’s worst water crises, triggered by record-low levels at La Mesa Dam.

The 2019 crisis forced reduced water allocations for both Maynilad Water Services and Manila Water.

Today, the dam is once again nearing critical levels.

With forecasts of a possible strong El Niño–Southern Oscillation that could persist until 2027, concerns are growing over another potential water crisis.

What has been done?

Since May 2026, the National Water Resources Board has suspended irrigation releases to prioritize water supply for Metro Manila.

The agency has also been exploring alternative water sources since March.

Meanwhile, the Climate Change Commission has urged local governments to strengthen climate adaptation measures, including sustainable water management, watershed protection, rainwater harvesting, and early warning systems.

For their part, Maynilad Water Services and Manila Water said they are continuously upgrading and maintaining their facilities to better meet customer demand.

What can the public do?

With water levels still falling, government agencies are urging the public to conserve water while rainfall remains insufficient to replenish major dams.

Officials warn that the public should not wait for another full-blown water crisis before acting, stressing that every drop counts.— Lyjah Tiffany Bonzo with research from GMA DigiLab/MCG, GMA News