“But I cannot give you an exact figure right now,” said John Yanis, acting chief executive officer.
The water catchment in the Yonki reservoir is used to produce hydro-electricity supplying the Ramu grid.
Morobe, Madang and Eastern Highlands are some provinces that benefit from power generated from the Ramu grid.
Meanwhile, Sirinimu Dam in the Central Province is facing the same fate.
“The water level is at 114 million cubic metres, 34 percent of the full capacity remaining,” Yanis said.