BOGO CITY, CEBU — A newly discovered sinkhole in northern Cebu is continuing to expand, prompting the Mines and Geosciences Bureau (MGB) Region VII to classify the area as a “high-risk ground collapse area” and recommend strict restrictions around the site.
The sinkhole is located in Sitio Indilicio, Purok Libog 1, Barangay Guadalupe, Bogo City. MGB-7 issued its geohazard threat advisory after technical personnel inspected the site on August 22 and 23, following the initial report of the ground collapse early on August 20.
The hole is still getting bigger
During the MGB assessment, the sinkhole measured approximately 15 meters by 25 meters and had already widened by about two meters.
More concerning, portions of the rim were continuing to collapse into the cavity below. Geologists also reported hearing rumbling sounds, which MGB said could indicate continuing subsurface collapse.
Field observations and drone imagery indicated a cavity beneath the surface, with an estimated depth of around 15 meters. The nearest house was reported to be only about 18 meters from the sinkhole’s rim.
MGB-7 also detected groundwater flow and geological conditions suggesting that the underground cavity may extend beyond what can currently be seen from the surface.
Experts still don’t know how far the cavity extends
The formation has been classified as a cover-collapse sinkhole—a type of ground failure that can occur when material above an underground cavity loses support and collapses.
Ground-penetrating radar (GPR) was used to investigate the area. However, the presence of clayey material weakened the radar signal beyond roughly five to six meters, preventing authorities from determining the cavity’s complete depth and lateral extent.
That means the visible opening may not reveal the full size of the underground void.
MGB-7 said two other cover-collapse sinkholes are located relatively close to the new site—one approximately 100 meters southwest and another about 65 meters northeast. Both reportedly formed following the magnitude 6.9 earthquake that struck Cebu on September 30, 2025.
The proximity of the three sinkholes raises the possibility that they could be associated with a larger underground cavity or conduit system, although this has not yet been confirmed.
Part of a larger sinkhole problem in northern Cebu
The development comes less than a year after the devastating magnitude 6.9 Cebu earthquake, which triggered reports of sinkholes, ground cracks and land subsidence across several northern Cebu communities.
In October 2025, MGB-7 confirmed sinkholes in areas including Bogo City, San Remigio, Medellin, Daanbantayan and other northern municipalities. At the time, affected areas with reported sinkholes were classified under high subsidence hazard warnings.
SunStar previously reported that MGB-7 had validated at least 70 sinkholes in northern Cebu following the 2025 earthquake, with San Remigio recording the largest number during that assessment period.
However, authorities have not established that the newly discovered August 2026 sinkhole was directly caused by the 2025 earthquake. MGB’s current findings point to an active underground collapse, while the relationship between the new formation and the earlier earthquake remains unconfirmed.
Authorities impose wider safety restrictions
Because the sinkhole remains active, MGB-7 has recommended that the Bogo City Government establish a no-entry zone of at least 20 meters from the rim.
A wider 50-meter controlled-access zone has also been recommended to limit unnecessary movement around the hazardous area.
Residents have been urged to remain alert for new cracks, unusual ground movement or sounds and immediately report changes to the Bogo City Disaster Risk Reduction and Management Office.
MGB-7 also advised residents in potentially affected areas to consider preemptive evacuation during periods of heavy rainfall, when ground conditions could become more unstable.
The warning authorities don’t want people to ignore
The danger is not limited to the visible hole.
The continuing collapse of the rim, the reported underground rumbling and groundwater movement indicate that the ground beneath the area may still be changing.
MGB-7 has therefore warned residents and the public not to approach the sinkhole simply to take photographs, videos or produce online content. Officials are also urging the public to rely on verified government advisories rather than unconfirmed social media reports.
For Bogo, the latest development is another reminder that the geological effects of the 2025 earthquake have not necessarily ended.
And with the underground cavity beneath the Guadalupe site still not fully mapped, the biggest question may no longer be how large the hole is—but how far the unstable ground could extend.
Leave a Reply