MANILA - Water level at Angat Dam slid further on Tuesday after breaching the critical mark, state weather bureau PAGASA said.

Angat Dam supplies water to Metro Manila and Central Luzon. As of 6 a.m., its water level was at 178.95 meters, below the 180-meter minimum level required for normal operations, according to PAGASA data.

LOOK: Angat Dam water level further declined to 178.95 meters today, April 30, breaching the 180 meters minimum requirement or the first critical level. | via @jacquemanabat pic.twitter.com/qzHTcvmUci

— ABS-CBN News (@ABSCBNNews) April 30, 2019

The water level could drop to 175.5 meters by the end of May, said the agency.

Water supply for agriculture next month would be reduced to 10 cubic meters per second from April's 35 cubic meters per second, the National Water Resources Board said Monday.

Allocation for domestic use was unaffected, but would be slashed if Angat Dam's water level falls to 160 meters, said PAGASA.

The dam's declining level, lack of rains due to El Niño, and high demand have been blamed for a water supply outage that brought misery to more than a million households in Metro Manila in March.

Report from Jacque Manabat, ABS-CBN News