Expert urges LGUs to strictly enforce construction laws

By Ernesto Delgado

MASBATE CITY --- Earthquakes do not kill, but the buildings and structures that collapse and the objects that fall during a tremor can lead to fatalities.

Geologist Deo Carlo Llamas, a science research specialist at the Philippine Institute of Volcanology and Seismology (Phivolcs), clarified this in a recent online forum with members of the Masbate Provincial Disaster Risk Reduction Council.

Llamas warned that certain areas within the Masbate segment of the Philippine Fault Zone are prone to repeated ruptures.

In a study of the Masbate Fault and the significant earthquakes that affected the region in less than two decades, Llamas noted that some residents in the municipalities of Dimasalang, Palanas, and Cataingan on Masbate Island reside near the fault line.

On August 18, 2020, amid the COVID-19 pandemic, Masbate was hit by a magnitude 6.6 earthquake centered in the coastal town of Cataingan, resulting in surface rupture, landslides, local tsunamis, at least one fatality and significant damage to a nearby building.

Previously, on February 15, 2003, the island was struck by a magnitude 6.3 earthquake with its epicenter located less than 40 kilometers northwest, in the town of Uson.

Geologist Deo Carlo Llamas examines a coconut tree split in half by a fault rupture during the 2003 earthquake in Masbate. The 2020 earthquake occurred at the same location where the coconut tree stood, further splitting what remained of the tree. (Photo from Deo Carlo Llamas)

Llamas said both seismic events were caused by the Masbate segment of the Philippine Fault, which has a history of deadly quakes.

This left-lateral strike-slip fault runs parallel to the arc and is highly active in Masbate province, where two other potentially active faults, the Uson Fault and the Southern Masbate Fault, are located.

Llamas noted that Masbate is among the most seismically active regions in the country, with large-magnitude earthquakes occurring as frequently as every 16 years based on historical data.

“Since earthquakes frequently occur in Masbate, it is important for us to be aware of the associated hazards,” he explained, mentioning ground shaking, ground ruptures, and tsunamis that can result from fault movement.

Llamas strongly recommended that local governments tighten the granting of building permits and closely monitor house construction to ensure that builders are adhering to construction laws.

Llamas said laws governing structures required designs and materials that could withstand a 7-magnitude or stronger quake.

Said he: “If you follow the National Building Code and the National Structural Code, your structure, or your house or commercial building will withstand an intensity 8 ground-shaking.”

“As you can see the maximum ground-shaking that can affect near the fault would be intensity 8,” he said.

He added that enforcing the building code at the grassroots level and ensuring community cooperation will reduce injuries, damages, and fatalities during earthquakes in the province.

Llamas said residents should understand hazards and warning systems, plan for risks to protect themselves and their families and build a basic disaster supply kit.

Phivolcs has installed markers along the fault lines to prevent construction on an active fault traces and within the 5-meter buffer zone.

The building code requires individuals to obtain a government permit before constructing any structure, including a fence. This process allows engineers to verify that the appropriate materials and designs are being used.

However, due to financial constraints, many people resort to saving money by building their homes in stages. They often complete the entire house before visiting the town hall to submit their “as-built plan” for approval. At this point, engineers can no longer assess the materials that were actually used in the construction.

This non-compliance by homeowners can lead to significant risks, including loss of lives and property during an earthquake. (PIA5/Masbate)