In a telephone interview, Mariton Bornas, chief of the Phivolcs volcano monitoring division, expressed concern for hundreds of folk who have built homes within the anti-lahar megadike at the Pasig-Potero River in Pampanga, as well as for folk mostly in San Marcelino and Castillejos in Zambales which are in dangerfrom lahar debris at the Sto. Tomas-Marella River.
“We did some inspection at the Sto. Tomas-Marella River and found out that a long stretch of its four-kilometer wide diking system midstream is full of volcanic debris about seven meters thick. Strong rains could remobilize these debris as lahar flows and hit populated areas, largely San Marcelino and Castillejos,” she said.
Bornas said that while almost all of the lahar materials spewed by Mt. Pinatubo during its 1991 eruption have already been washed down from the volcanic slopes, much of the materials have remained along the channels around the volcano and still could be pushed by heavy rains to lowland populations.
“In the case of the Pasig-Potrero River where the U-shaped anti- lahar megadike was built to catch lahar flows, immediate danger face families which have built homes within the megadike. All areas within the megadike are supposed to be dangerous off -limits zone,” she stressed.
Hundreds of folk have rebuilt their homes within the megadike which had served as catch basin for lahar debris that had fl owed through the Pasig- Potero river.
“It would seem that unless serious danger befall these areas, the residents in these areas would not abandon their homes, so the option in the meantime is to keep them aware of the risk they are facing and alert them in case of immediate danger,” Bornas said.
She noted that a portion of the megadike along the Pasig-Potrero has also accumulated lahar debris higher than the ground level outside the diking system in the area of Barangay Dolores near Bacolor town in Pampanga. This area, she noted, could pose risk to folk in nearby communities.
Earlier, Phivolcs director Rene Solidum said that while the Pasig-Potrero megadike had effectively shielded the capital city of San Fernando and other Pampanga towns from being buried by lahar, the dike has yet to experience the so-called “siyam-siyam” flooding event similar to that which inundated the entire Central Luzon in 1972.
