MANILA, Philippines – The Office of Civil Defense (OCD), led by Directors Cesar Idio and Agnes Palacio, convened an urgent meeting with various government agencies to address preparedness and response measures following a series of offshore earthquakes near Santa Catalina, Ilocos Sur.
Since December 17, 2024, at 3:00 PM, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) has recorded 49 earthquakes, ranging from magnitude 1.8 to 5.0. The seismic activity is centered approximately 100 km west-northwest of Santa Catalina. Experts warn of two potential scenarios: the gradual decline of seismic activity or the possibility of a stronger earthquake that could trigger a tsunami. The latter scenario has become the focus of contingency planning discussions by the National Disaster Risk Reduction and Management Council (NDRRMC).
Monitoring and Data Collection
PHIVOLCS has reported 55 located events since the activity began, including a notable magnitude 5.0 quake. A robust network of 121 seismic monitoring stations, complemented by seven volcanic observation stations, continues to provide real-time data. The earthquakes are attributed to movements near the Manila Trench. Residents in Santa Catalina and nearby areas have reported experiencing tremors, heightening concerns in local communities.
Tsunami Risk Assessment and Forecast
PHIVOLCS has identified key tsunami forecast points, projecting significant risks for coastal areas:
Calayan, Cagayan: 2.5 meters in 10 minutes
Pagudpud, Ilocos Norte: 7.6 meters in 3 minutes
Laoag City, Ilocos Norte: 10 meters in 5 minutes
Vigan City, Ilocos Sur: 14.7 meters in 4 minutes
San Fernando City, La Union: 11 meters in 6 minutes
Bolinao, Pangasinan: 11.6 meters in 15 minutes
Palauig, Zambales: 4.8 meters in 2 minutes
Worst-case scenarios outlined in the Region 1 Contingency Plan suggest inundation levels exceeding 6 meters in parts of Pangasinan and La Union, with wave heights ranging from 7 to nearly 12 meters in affected provinces.
Local Government and Agency Response
OCD Region I has activated its contingency plan, identifying over 700 barangays across Pangasinan, La Union, and Ilocos Sur that may be impacted. The Department of Health (DOH) has advised local government units (LGUs) to establish dedicated evacuation centers for tsunami threats, separate from those designated for tropical cyclones.
The Philippine Coast Guard (PCG), Bureau of Fire Protection (BFP), and Philippine National Police (PNP) are tasked with assisting LGUs in disseminating safety information and mapping safe high-ground areas. The Department of the Interior and Local Government (DILG) is expected to issue advisories on the potential tsunami threat and ongoing seismic activity.
Worst-Case Scenario Planning
Regions I, II, and III are revisiting their contingency plans to prepare for a potential Magnitude 8.2 earthquake originating from the Manila Trench, which could generate a devastating tsunami. Authorities are urging all agencies and communities to remain vigilant and proactive.
Community Preparedness
Officials stress the importance of public awareness and preparedness. Residents are urged to stay informed through official updates and adhere to evacuation protocols. “Preparedness and vigilance are critical in mitigating risks and ensuring the safety of our communities,” the OCD stated in its advisory.
As the situation develops, the government remains committed to safeguarding lives and property, prioritizing proactive measures to address potential seismic and tsunami threats.