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Manila Bulletin devider Philippines devider Metro Manila devider Muntinlupa LGU places permanent fault markers for the 'Big One'

Muntinlupa LGU places permanent fault markers for the 'Big One'

Published Apr 9, 2026 09:36 am
A permanent West Valley Fault marker in Barangay Sucat, Muntinlupa (Photo from Muntinlupa PIO)
A permanent West Valley Fault marker in Barangay Sucat, Muntinlupa (Photo from Muntinlupa PIO)

The Muntinlupa City government has begun installing permanent West Valley Fault markers as part of its awareness and preparation campaign for the so-called “Big One” earthquake.  

Mayor Ruffy Biazon led the launch in Barangay Sucat, joined by Director Teresito Bacolcol of the Department of Science and Technology-Philippine Institute of Volcanology and Seismology (DOST-Phivolcs), City Director Mary Anne Planas of the Department of the Interior and Local Government (DILG), Sucat Barangay Captain Raffy Sevilla, and the Muntinlupa City Department of Disaster Resilience and Management. 

The West Valley Fault system is an imaginary line that marks areas where the fault systems are located underground and traverses Bulacan, Rizal, Metro Manila, Cavite, and Laguna.

Phivolcs said in 2016 said the “Big One” refers to an earthquake with a magnitude of no less than 7.2 in the Richter scale, which may be experienced in the country. 

“Also, there are specific locations that are considered most vulnerable to said earthquake because of their proximity [to] the so-called West Valley Fault,” according to the statement.

Biazon said the fault markers will be placed in eight of the nine barangays in Muntinlupa that are traversed by the fault line. 

“Dati na tayong may nilagay na temporary markers pero ngayon, mas pangmatagalang gabay na ito para matukoy kung saan eksaktong dumadaan ang active fault line sa lungsod (We have previously placed temporary markers, but now, this is a more permanent guide to determine exactly where the active fault line passes through the city),” said Biazon. 

Each marker has the warning "Ang lugar na ito ay dinadaanan ng West Valley Fault (This area is traversed by the West Valley Fault).”

He added, “Knowing where the fault is is already a big step para makaiwas sa mas malaking pinsala (Knowing where the fault is is already a big step to avoid greater damage).” 

The marker, he said, is also a visual warning for residents and developers to avoid building structures in high-risk areas. 

Biazon said they have done the “Walk the Fault” numerous times or visited barangays traversed by the fault. 

“Kaya tuloy-tuloy ang awareness at preparedness efforts natin (That is why our awareness and preparedness efforts are ongoing),” he said. 

Fault system (Screenshot from PHIVOLCS' Fault Finder app)
Fault system (Screenshot from PHIVOLCS' Fault Finder app)
Muntinlupa Mayor Ruffy Biazon greeting Director Teresito Bacolcol of the Department of Science and Technology-Philippine Institute of Volcanology and Seismology (Photo from Muntinlupa PIO)
Muntinlupa Mayor Ruffy Biazon greeting Director Teresito Bacolcol of the Department of Science and Technology-Philippine Institute of Volcanology and Seismology (Photo from Muntinlupa PIO)
A permanent West Valley Fault marker in Barangay Sucat, Muntinlupa (Photo from the Muntinlupa City Department of Disaster Resilience and Management)
A permanent West Valley Fault marker in Barangay Sucat, Muntinlupa (Photo from the Muntinlupa City Department of Disaster Resilience and Management)
Muntinlupa Mayor Ruffy Biazon, DOST-PHIVOLCS Director Teresito Bacolcol and Sucat Barangay Captain Raffy Sevilla putting up the marker in an area in Sucat, Muntinlupa (Photo from Muntinlupa PIO)
Muntinlupa Mayor Ruffy Biazon, DOST-PHIVOLCS Director Teresito Bacolcol and Sucat Barangay Captain Raffy Sevilla putting up the marker in an area in Sucat, Muntinlupa (Photo from Muntinlupa PIO)
A permanent West Valley Fault marker in Barangay Sucat, Muntinlupa (Photo from the Muntinlupa City Department of Disaster Resilience and Management)
A permanent West Valley Fault marker in Barangay Sucat, Muntinlupa (Photo from the Muntinlupa City Department of Disaster Resilience and Management)

Related Tags

Muntinlupa West Valley Fault Big One earthquake PHIVOLCS Barangay Sucat Muntinlupa
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