By Dominique Gabriel G. Bañaga

Fishermen from Purok Malipayon in Barangay Sibucao, San Enrique, Negros Occidental expressed their fears in a radio interview over the weekend after a portion of the riverbed in the Candaguit River rose out of the water.

Rex Nebril and Ernesto Suanico said they were fishing when the earthquake occurred. The two reported hearing a “growling noise” around 50 meters away and assumed there may have been a large animal wading in the water.

Upon closer inspection, they found three feet of the riverbed had risen out of the water.

The two also claimed to have seen smoke.

Following the incident, Bacolod City Disaster Risk Reduction and Management Office (CDRRMO) head Joemarie Vargas said the rise of the riverbed may have been caused by a build-up of either nitrous oxide or methane gas.

Vargas said nitrous oxide has a similar odor to rotten eggs and it is possible a large tree may have been swept into the area and got buried beneath the river.

The gas eventually builds up, following years of decomposition, until the pressure triggers the riverbed to rise up.

“It’s just like what you see with buried garbage,” he explained. “If you bury it for too long, it [will] eventually create methane gas.”

“However, since this was located in the marshland then it is most likely nitrous oxide,” he explained.

Vargas also stated such incidents are normal and people should not to be alarmed; although he advised San Enrique officials to prevent anyone from swimming in the said area as it is possible there is still a pocket of gas, which could cause it to collapse and create a large hole.

He added, town officials should have geologists survey the area.

The CDRRMO head also assured the incident was not connected in any way to the volatility at Mt. Kanlaon, which is presently under an ‘Alert Level 2’ status./DGB, WDJ