The Department of Environment and Natural Resources’ Mines and Geosciences Bureau (DENR-MGB) has observed and documented sinkholes in three villages of the world famous Boracay Island since 2018.
Mae Magarzo, MGB chief geologist in Western Visayas, cited the latest geological survey showing that the number of sinkholes in the island has increased.
She fears that the island might collapse as 815 sinkholes have been discovered.
Data showed that the number of sinkholes on the island went up from 798 in 2018 to 801 in 2019, 814 in 2020, and 815 between 2021 and 2022, in barangays Balabag, Manoc-manoc and Yapak.
Magarzo stressed that the island’s current physical carrying capacity must be strictly implemented amid increasing number of infrastructures being built on the island.
She raised concern that sinkholes could cause the ground to collapse, and that such occurrence is difficult to determine, unlike the occurrence of landslides through the observation of cracks or lowering elevation.
“We can see that there are more holes. The danger is, if the island is over-capacitated in structures, there would come a time when many (of these) structures might collapse,” she said.
Based on the DENR “subsidence susceptibility map,” the island in Malay town is highly susceptible to subsidence or ground sinking as it also sits on a fault line.
Magarzo said the island is made of limestone that is vulnerable to sinkholes.
Boracay’s carrying capacity assessment in 2018 showed structures built on the island had exceeded the ideal number.
There are at least 10,250 houses on the island or 4,712 units more than the 5,538 real carrying capacity for residential structures.
The island has 2,779 business establishments, 878 units more than the 1,901 RCC for business.
Boracay has a tourist carrying capacity of 19,215 or a daily capacity of 6,405.
Malay, Aklan Mayor Floribar Bautista said Boracay receives about 4,000 tourists daily, which is still within the island’s carrying capacity as allowed by the government.
Bautista issued the statement on the heels of the MGB’s disclosure that more than 800 sinkholes have appeared on the island.
“Basta hindi tayo bababa sa 4,000 a day…ang mga residents na lang sa Boracay nasa 38,000 yan eh,” Bautista told TeleRadyo.
“Ang anong capacity kasi dyan ng Manila 6,400 or 6,500 tourists a day,” he added.
The mayor said they are strictly implementing the rules when it comes to the number of visitors allowed on the island.
“Kung pag-usapan naman natin sa carrying capacity eh ino-observe naman natin yan eh.”
“At regarding naman sa mga structure, meron kaming mga regulations sa Boracay na wala naman tayong masyadong high-rise. Ang maximum natin height sa Boracay 6 floors eh.”
He added, however, that he wants the MGB to show him a map of where sinkholes were found in Boracay.
“At dapat din ma-identify kung saan banda yang mga sinkhole na yan. Manghingi ako ng mga mapa dyan sa MGB para malaman natin kung ganoon kalaki at hindi paglagyan ng structure dyan kasi merong sinkhole.”
All structures in Boracay are built properly, he said.
“Lahat naman ng mga structures, lalo na malalaki yung mga matataas na mga structures …hindi naman basta-basta yung mga structure engineer na tinitingnan talaga sa may ilalim kung may hollow ba siya or may sinkhole ba,” he noted.