By CESAR JOLITO III
Negros Occidental Governor Eugenio Jose Lacson called on all local government units (LGUs) in the province to prepare for the possibility of the “Big One” — a massive magnitude 8.2 earthquake — which could strike the province due to the Negros Trench.
“While we always hope it will not happen, we should be prepared,” Lacson said, referring to the possibility of a major seismic event.
Lacson said the provincial government will conduct a province-wide structural assessment of all its buildings, which aims to ensure the structural integrity of government facilities and public infrastructure following warnings from the Philippine Institute of Volcanology and Seismology (Phivolcs).
He also urged LGUs across the province to carry out similar evaluations within their jurisdictions.
“That is exactly what Department of Science and Technology [DOST] Secretary Renato Solidum was telling us. We should really reinforce our buildings, just to make sure they can withstand a six or seven intensity,” Lacson pointed out.
The 400-kilometer-long Negros Trench, located west of the Negros Island Region, is one of the country’s most active undersea fault systems.
Recent seismic activity has heightened public concern, including a magnitude 6.9 earthquake in northern Cebu in September and a magnitude 7.4 quake in Davao Oriental — both felt across parts of the Visayas and Mindanao.
Lacson noted that the sinkholes and ground cracks recently discovered in Sipalay City, which lies near the Negros Trench, could be linked to the series of quakes recorded in the region.
“Sipalay has experienced more earthquakes compared to other LGUs in Negros Occidental,” he added.
During the Handa Pilipinas sa Bagong Pilipinas Expo 2025 (Visayas Leg) held at the SMX Convention Center in Bacolod City on Monday, October 27, Phivolcs Director Teresito Bacolcol said a shallow and powerful tremor from the Negros Trench could also trigger tsunami waves, affecting the western coastlines of Negros, Panay, Zamboanga, and Palawan.
“A magnitude 8.2 earthquake from the Negros Trench could rock the entire Negros Island,” Bacolcol said.
While the West Valley Fault in Metro Manila continues to pose the risk of a magnitude 7.2 earthquake — dubbed the “Big One” — Bacolcol stressed that similar large-scale quakes could also occur elsewhere in the country, including the Visayas.
Bacolcol cautioned coastal residents to recognize the natural signs of a tsunami, emphasizing that waves could arrive within five minutes of a major tremor.
“If you feel strong shaking that makes it hard to stand, notice the sea suddenly receding, or hear a roaring sound from the ocean — even just one of these signs means you must immediately run for higher ground,” he added.
The Phivolcs chief underscored that public awareness and quick response remain the most effective defense against such natural hazards.
According to Phivolcs, the Philippines experiences around 30 earthquakes daily, most of which are too weak to be felt but are recorded by instruments./CJ, WDJ