The official, who requested anonymity, said the Angat water reservoir continues to decline steeply despite massive diversion of water from as far as the Umiray River in Quezon last month.
As of last Thursday, the Angat Dams water level had fallen to its "180-meter lower rule curve" or at 179.09 meters according to the top MWSS official.
Based on projections of the National Water Resource Management Board, the dams water level should be 182.7 meters in anticipation of the El Niño phenomenon.
Although the board anticipates the Angat water level to rise only in August, it did not expect the sudden drop, the official said.
Based on MWSS records, the water level dropped at an average of .15 meters in June. Between June 26 and 27, however, the decline was .47 meters and "this appears to be the new trend," the official said.