Lahar from Mayon slopes threatens Albay villages

Mayon Volcano displays a crater glow in this photo taken on June 9, 2023. Photo from Phivolcs.

LEGAZPI CITY—Residents in Albay are bracing for the possibility of rain-triggered lahar flow from the slopes of Mt. Mayon as the volcano continues to show signs of heightened activity this week.

Levy Lourdes Nuñez, village chief of Mabinit here, said the newly emitted volcanic materials and the old deposits from Mayon might be carried down by rainwater along the Bogña gully in their adjacent barangay now that the rainy season has started.

“Another hazard that makes us fearful is the flooding with lahar flow. We are afraid that the quarry operations on the slopes of the volcano could open the channels leading to our village,” Nuñez said in a phone interview on Wednesday.

Ruthie Pacala, forecaster at the Philippine Atmospheric, Geophysical and Astronomical Services Administration Legazpi, said Tropical Storm “Chedeng” (international name: Guchol) would not directly affect or bring heavy rainfall to the province. Albay, she said, is expected to experience only light to moderate rains and thunderstorms in the next few days.

Nuñez said all 390 households, or more than 1,700 residents, within the 8.5- to 9-kilometer radius of Mayon were always evacuated during every volcanic eruption.

Miladee Azur, head of the disaster risk reduction and management office, said the evacuation orders would be based on the assessment of risks in the affected areas.

“There is a threshold of rainfall volume that could generate lahar, and we have an alert level system based on rainfall volume, which informs the actions to be taken by the communities,” Azur added.

Paul Karson Alanis, resident volcanologist at the Philippine Institute of Volcanology and Seismology (Phivolcs) Legazpi, said the volume of new deposits was still small but this might add to the old deposits during lahar flow.

In its Wednesday bulletin, Phivolcs said it recorded 46 rockfall events over a 24-hour monitoring period.

Phivolcs raised Mayon’s warning status to alert level 2 on Monday due to “shallow magmatic processes” that could lead to phreatic (steam-driven) eruptions or hazardous magmatic eruptions.

In Batangas province, Talisay Mayor Nestor Natanauan suspended classes in public and private schools on Wednesday due to the continued volcanic sulfur dioxide emission from Taal Volcano which remains under alert level 1.

Natanauan, in a Facebook post Wednesday, said he suspended classes after vog (volcanic smog) reached the town. Vog consists of fine droplets containing acidic volcanic gas. It causes irritation to the eyes and throat and it can be harmful to persons with respiratory illness.

In its 11 a.m. advisory on Wednesday, Phivolcs reported “ongoing degassing activity” at Taal Volcano over the past 24 hours.

READ:

Gov’t ready for disaster in case Mayon will erupt – Marcos

Mayon: Alert Level 3 up as rockfalls increase; ‘explosive activity’ seen in weeks- Phivolcs

—WITH A REPORT FROM DELFIN T. MALLARI JR.