MANILA - Super Typhoon Rolly left some P5.8 billion in infrastructure damage in Bicol region after pummeling Luzon on Sunday, the Department of Public Works and Highways said Thursday.

The strong winds and torrential rains of Rolly, the world's strongest storm so far this year, destroyed majority of the region's flood control structures, according to DPWH Secretary Mark Villar who inspected the area Wednesday.

"First thing we wanna secure is the residents there. The damage in the dikes - we want to plug it as soon as possible. We still want to be ready in case there might be another low pressure area or typhoon. We wanna make sure the safety infra are repaired," he told ANC's Headstart.

The national roads in island province Catanduanes remain impassable but it will be cleared in the next few days, Villar added.

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Meantime, the agency also needs to desilt rivers in Guinobatan town, where Rolly brought down debris and boulders from Mayon Volcano to communities, leaving at least 3 dead.

• Bicol death toll from super typhoon Rolly drops to 19 after report confirmation

"The volume of debris coming from Mount Mayon is very massive. After every eruption those debris actually accumulate. If there’s heavy rain and it comes down, it overwhelms the safety measures we put up," Villar said.

"We have to see what areas are prone to that kind of landslide. We have to further improve our safety infrastructure."

As for quarrying, Villar said the process of operators must be monitored to "prevent a similar incident in the future."

• Albay gov says to suspend quarrying operations after Rolly devastation

The environment department had suspended quarrying operations around the volcano after its initial investigation showed some of the quarry operators left their stockpiles in the middle of the rivers, which were then washed away when floodwaters flowed down from Mayon Volcano.

Albay Governor Al Bichara said the debris and boulders that Rolly swept into a community in Guinobatan town were from the top of Mayon Volcano and not from quarry stockpiles.

• Lahar slide in Guinobatan due to volcanic debris, not quarrying: governor
• Cimatu suspends quarrying operations around Mayon Volcano

"Regardless of quarrying the debris is still there. It has to be removed," Villar said.

The agency has about P1 billion in quick response fund for disasters that can be replenished, the secretary said.

"We’re expecting a new replenishment. Next batch we’ll be focusing on structures affected by Typhoon Rolly," he said.

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