Landslide-hit Agusan-Bukidnon trade route unlocked after redesign

SAN FRANCISCO, Agusan del Sur — Government engineers are carrying out major repairs to stabilize a landslide-hit mountain highway linking Butuan City in Agusan del Norte and Bukidnon province, a key route expected to boost agricultural trade between Caraga and Northern Mindanao.

The road project runs along the Butuan City–Malaybalay road corridor in Tungao, Butuan City, connecting Sitio Danapa to the Lingayao–Lawan-lawan road in Barangay Durian, Las Nieves.

The corridor serves as a crucial transport lifeline for the LASBUENASCAR alliance, an economic partnership named after four neighboring towns in western Agusan del Norte: Las Nieves, Buenavista, Nasipit, and Carmen.

READ: House passes infrastructure strategy bill on final readingThe road project aims to link inland farming communities directly to coastal trading centers. Landlocked Las Nieves serves as the agricultural hub, growing rubber, oil palm, timber, bananas, and root crops. Meanwhile, the coastal towns of Buenavista, Nasipit, and Carmen host processing plants, markets, and sea transport through the Port of Nasipit.

Once the highway is stabilized, it will give local farmers and Bukidnon growers a faster, direct route to regional markets in Butuan City and nearby ports.

Contractor ML Builders began work on the original road on August 22, 2022, and completed its construction on December 2, 2024. But relentless rains soon caused the roadside slopes to cave in, cracking the newly poured concrete and tearing away road shoulders.

The original design used stone-and-mortar retaining walls (riprap), which, however, could not hold back soaked earth. Although the contractor repaired the section twice, the hillside kept collapsing after heavy rains.

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“It rained continuously at the time, causing structural damage,” Engr. Edwin Salome, DPWH project inspector, said in Bisaya during a briefing.

“They repaired it twice, but the slope kept collapsing. So we asked our planning engineers to inspect the area and study what was causing it,” he added.

Soil and geological tests conducted by the DPWH regional office found the underlying problem: a loose, muddy top layer resting directly on slick, hard rock beneath. Whenever heavy rains soaked the ground, rainwater seeped between the two layers, making the surface slippery and causing the entire hillside to slide off the rock base like a ramp.

READ: DPWH eyes tech options to control landslides

To stop the recurring collapses, engineers replaced the simple stone walls with heavy interlocking steel sheet piles driven deep into the ground, reinforced by solid concrete anchor blocks called “deadman” piles.

Pile driving began on February 11, and DWPW officials expect to complete work in December.

DPWH officials noted that because the road is still within the warranty period, ML Builders is footing the entire bill for the repairs and redesign./coa