DAVAO CITY—The City Disaster Risk Reduction and Management Office (CDRRMO) of General Santos City said on Friday that the dark blue-colored elliptical portion of its sea as seen from aerial photographs was “a case of coastal subsidence and not the feared sinkhole.”
Bong Dacera, CDDRMO action officer, made the clarification before the residents of Purok Tinago of the coastal village of South, who have expressed anxiety over an alleged sinkhole beginning at the coastal portion and extending several nautical miles further south of this tuna capital of the country.
“It is not a sinkhole but rather an underwater soil erosion. What is taking place now in Purok Tinago is a case of coastal subsidence and not the feared sinkhole,” he told the public gathering at the Irineo Santiago National High School.
“Only the Mines and Geosciences Bureau [MGB] can declare if that is the sinkhole. But, as of now, based on our assessments, it is a coastal subsidence,” Dacera said.
“A few meters from the shores of Tinago, there is an underwater precipice around 25 meters deep. Throughout the years, the movement of the sea has eroded parts of this cliff, thus causing the erosion,” Dacera explained.
He said, “if you are to compare it with surface phenomenon, what happened there is definitely a landslide.”
The MGB has released a one-page report that supported the preliminary explanation of the CDRRMO.
A team of geologists from the national office of the MGB was scheduled to make an underwater study “any moment this week at Tinago to inspect and assess the erosion,” the General Santos City information office said.
The office said the results would be used by the city government and the CDRRMO “for disaster-proofing of Barangay South and nearby coastal communities.”
City Mayor Ronnel Rivera has ordered the mandatory evacuation of Tinago while waiting for a confirmatory finding from the MGB divers.
Thirty-seven families would be transferred to the relocation site Promise Land in Barangay Mabuhay. The rest of the residents of 9A Tinago and 9B Tinago would be relocated to a 3-hectare land in Purok Lanton, Barangay Apopong.
Rivera has promised the residents to relocate within three months, with each family being given lots of 75 square meters each.
“Actually, this is hard task but since this is very immediate, I have to make arrangements so that residents in Tinago can be relocated and be moved away from danger as soon as possible,” Rivera said.
The city government said the erosion, “if it gets wider, could affect 1,000 more families and even nearby villages such as Purok Islam.”
Rivera already declared Tinago a “no-build zone” to restrict anyone from erecting any form of house or establishment there.
The erosion has extended 100 meters to the sea. In an aerial view, the collapsed portion is visible and distinct compared to the surrounding shores, the city government said.
Locals have estimated that the entire scope of erosion is around 70 meters wide and around 640 meters deep.