Sinkhole stirs folk in Barili

CEBU, Philippines - A sinkhole was discovered in the middle of the Mantayupan River in Barili town Tuesday afternoon causing fear among residents living in the area.

The sinkhole, which is located two kilometers upstream of the Mantayupan Falls, measured two-feet in diameter and about 12-feet deep.

Barili Mayor Teresito Mariñas said the sinkhole was first discovered by the caretaker of the private lot owned by the Tanchans. The caretaker was gathering stones for the landscape as the area is being developed into an eco-tourism park when he heard a loud explosion from the river.

Mariñas said the caretaker allegedly noticed a whirlpool-like movement of the water in the river. In about four hours the water level in the river started to subside.

“Kalit lang kuno kaayo nihubas na ang sapa nga taga-tuhod lang, tanan didto gyud padung sa bangag (the knee-deep water level in the river allegedly subside because it was funneled into the hole),” Mariñas said in a phone interview.

Mariñas believes that there could be an underground river in the place. Local officials have already cordoned off the area and started filling the sinkhole with earth materials. The Mayor said they are afraid that the sinkhole would dry up their waterfalls, which is the town’s water source.

The Mantayupan Falls, aside from being the water source for the irrigation, it has also powered the mini-hydroelectric turbine that supplies one megawatt of electricity to Cebu Electric Cooperative.

“Guidili ang manglaba, maligo ug magpaduol sa lugar (washing clothes, bathing and going near the area is prohibited)” Mariñas said.

Municipal Environment and Natural Resources officer Edwin Quiros said they have already sent a letter to the Mines and Geosciences Bureau (MGB) to inspect the place.

In an interview over TV Patrol Central Visayas, the MGB explained the possibility of an underground river beneath.

Sinkhole is part of the slow, natural process of erosion of limestone terrain that occurs over thousands of years. These common geologic phenomena generally occur where the limestone is within a few hundred feet of the land’s surface.

It is formed when rainfall percolating, or seeping, through the soil absorbs carbon dioxide and reacts with decaying vegetation, creating a slightly acidic water. That water moves through spaces and cracks underground, slowly dissolving limestone and creating a network of cavities and voids. As the limestone dissolves, pores and cracks are enlarged and carry even more acidic water. Sinkholes are formed when the land surface above collapses or sinks into the cavities or when surface material is carried downward into the voids. — (FREEMAN)