Post-Disaster Assessment of Landslides in Batangas after STS Kristine

 

Severe Tropical Storm Kristine brought heavy rainfall to Batangas, resulting in widespread flooding, numerous landslides, and lahar flows, particularly in the western part of the province near Taal Lake, on October 24, 2024. In response, the UP Resilience Institute (UP RI) conducted post-disaster hazard assessments from November 6 to 15, aimed at evaluating the impacts and extent of these hazards.

Led by UP RI Executive Director Dr. Alfredo Mahar Francisco Lagmay, the research team carried out geologic fieldwork across affected municipalities, including Agoncillo, Talisay, and Laurel, in the Taal Caldera area.

The UP RI field team meets with Talisay Municipal Mayor Hon. Nestor D. Natanauan and Talisay Municipal Administrator Alfred S. Anciado.

Before the fieldwork, the team utilized satellite imagery from Planet to identify landslides and flood-affected areas. During the field assessment, they conducted drone surveys, mapped landslide scars and deposits, and studied displaced materials. The team also collected rock and soil samples to analyze the composition and causes of the disasters.

The UP RI field team conducting drone surveys and hazard impact assessment in Talisay (left) and Laurel (right).

The fieldworks included validating existing NOAH hazard maps and gathering disaster details through interviews in affected municipalities. Data from these activities are being analyzed to pinpoint the primary causes of landslides and lahar flows.

Flood (blue and purple) and landslide (green) hazard maps of Laurel, Batangas in the UP NOAH website.

Preliminary findings, including drone survey results and field validations, were presented at the Agoncillo Municipal Hall. Recommendations for policymaking and rehabilitation efforts were also shared to guide recovery initiatives in disaster-affected areas.

UP RI field team assessing different coastal municipalities around Taal Lake.

UP RI aims to identify the contributing factors behind the landslides and lahar events in the Taal area, predict future hazards, and develop effective mitigation strategies to reduce risks for local communities.