Lahar around Kanlaon Volcano possible amid Ada —PHIVOLCS

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) on Friday warned communities around Kanlaon Volcano in Negros Island to brace for possible lahars amid rainfall from Tropical Storm Ada.

In an advisory, PHIVOLCS said rains from Ada could trigger volcanic sediment flows, muddy runoff, and siltation in rivers and drainage areas around the volcano.

“Prolonged heavy rainfall could generate life-threatening lahars and sediment-laden streamflows on major channels draining the southern, western and eastern slopes of Kanlaon Volcano,” PHIVOLCS said.

“Post-eruption lahars can be generated by heavy rainfall eroding loose material from remnant pyroclastic density current deposits of recent explosive eruptions and loose ashfall mostly from recent ash emission events,” it added.

Non-eruption lahars may occur if upper slopes recently exposed by landslides or weakened by Tropical Cyclone Tino in November 2025 collapse, sending debris into rivers that have already caused destructive flooding in downstream communities.

Communities of Bago City, La Carlota City, La Castellana, Moises Padilla and San Carlos City, Negros Occidental and Canlaon City, Negros Oriental along the following channels may be affected by lahars:

• Ibid River
• Cotcot River
• Talaptapan River
• Malaiba River
• Panubigan Creek
• Buhangin – Indurayan River
• Najalin River
• Inyawan River
• Maragandang River o Panun-an Creek
• Intiguiwan River
• Camansi River 
• Maao River 
• Tokon-tokon River
• Masulog River
• Binalbagan River
• Taco Creek
• Linothangan River

PHIVOLCS advised concerned communities as well as those further downstream to be prepared in case evacuation becomes necessary and to avoid traversing affected streams even those farther downslope.

“Kanlaon lahars, which were shown by Supertyphoon Tino to be strong enough to transport enormous volumes of gravel and boulders, could threaten communities by their force of impact, inundation, burial and wash out,” it said. —VAL, GMA Integrated News