Portion of Pansipit River in Taal dries up; Phivolcs explains why

Published January 15, 2020, 12:00 AM

by manilabulletin_admin

By Aaron Recuenco

TAAL, Batangas—Fear gripped residents here after part of a major river system that runs in this town suddenly dried up early Wednesday morning, triggering speculations that Taal Volcano is gathering strength for a more destructive eruption.

lolo peping  shows the empty water of pansipit river in taal batangas  due to Taal Volcano's eruption(photo by ali vicoy)
Lolo Peping shows the empty water of Pansipit River in Taal Batangas due to Taal Volcano’s eruption (Photo by Ali Vicoy)

But why did a portion of the Pansipit River, which hosts a regular fluvial parade, suddenly dry up?

Dr. Winchell Sevilla, of the Volcano Monitoring Department of the Philippine Institute of Volcanology and Seisnology (PHIVOLCS), explained that what happened to the Pansipit River is indeed Taal Volcano eruption-related.

He said given magma activity inside the volcano, the tendency is for the ground to swell because of magma accumulation. The areas where ground swelling has been monitored are Lemery, Taal, and other areas close to Taal Volcano.

“And since the natural flow of water in the river is that it goes to the lower areas, a portion of the Pansipit River dried up possibly because of the swelling or bulging of the ground in the area,” Sevilla told the Manila Bulletin in an interview.

As a consequence, the natural flow of water at a portion of Pansipit River at Barangay Tatlong Maria in Taal was disturbed. Water could no longer flow because the ground suddenly lifted up.

Another explanation, which is unlikely, according to Sevilla, is that there is a blockage that blocks the flow of water from the source.

So where did the water go?

One explanation is that the water was stuck in the lower areas since its natural flow was disrupted by the sudden swelling of the ground.

Another logical explanation, Sevilla said, is that the water that was supposed to flow along the Pansipit was absorbed by the fissures that have appeared in the past days.

Based on the situation report from the Batangas Provincial Disaster Risk Reduction and Management Office (PDRRMO), fissures or large cracks were observed in Sinisian, Mahabang Dahilig, Dayapan, Palanas, Sangalang, and Poblacion in the town of Lemery; Pansipit in the town of Agoncillo; Poblacion 1, Poblacion 2, Poblacion 3, and Poblacion 5 in the town of Talisay; and in the Poblacion area of San Nicolas town. A fissure was also documented across the road connecting Agoncillo to Laurel.

“The drying up of the river is consistent with the fissures that were seen in the areas near the volcano,” Sevilla said.

Unsafe ground

And what does this indicate?

The message is simple, according to Sevilla: It is not yet safe to return to the areas which were earlier recommended to be evacuated.

“This is the reason why Taal is still under Alert Level 4. There is still a lot of activity, so it is not yet safe for them to go back to their homes,” Sevilla told the Manila Bulletin.

Alert Level 4, he said, means that hazardous eruption is still imminent anytime although Taal Volcano has started to show a lull in gas and ash emissions.