By Venus H. Sarmiento, PIA 1, Pangasinan
DAGUPAN CITY — The San Roque Dam in San Manuel town maintained its safe water level despite the entry of two recent storms that affected Pangasinan
Valeriano Baro, principal engineer of the National Power Corporation-flood forecasting and warning system for dam operations, said the dam maintained its water level of 234 meters above sea level as of early July.
He said the dam has not released water through the spillways because water inflow from the Agno River is still low for San Roque Dam to react.
“During a typhoon, we are torn between two big rocks … whether or not to release to keep waters for farmers which they can use in the event of an El Nino,” Baro said during the KBP Forum held at the Philippine Information Agency office on Thursday.
Baro enumerated four criteria that NPC follows for dam discharge operations.
First, when water level reaches 280 meters; second, the area is under typhoon marking area 1 (per NPC map); third, the Agno River basin rain gauge reaches at least 60 millimeter rainfall for a day and fourth, when water level in reservoir registers at least 500 cubic meter per second.
“All four must be present. (But) there are also other factors that need to be considered for dam release,” he said.
Baro said even at 275 meters, NPC can release water if there is a forecast that dam level could reach the 280 meter-mark. NPC also considers storing water for farmers’ use during drought.
NPC has just finished its maintenance period from March to May and is now ready for the rainy season, he added.
San Roque Dam, the biggest earth dam in Asia, was built for power generation, irrigation, water quality and flood control.#