DPWH explores modern mountain technology to curb landslides

The Department of Public Works and Highways (DPWH) said it is eyeing modern mountain technologies to solve the persistent erosion problems besetting the Cordillera region.

"Hindi na pwede iyong mga ginagawa natin noon, hindi na pwedeng ganun pa din tayo hanggang ngayon. Gagamit na tayo ng bagong technology and new methods para mas matibay na at mas tatagal (Our practice before is no longer applicable at this time; we cannot be like that anymore. We will be using new technologies, new methods that are sturdier and will last longer)," Public Works Secretary Vince Dizon told reporters after inspecting several rain-induced landslides and rockslides that damaged public infrastructures in Baguio City and Benguet province on Friday.

He noted that while new technologies will be more expensive, they will be cheaper in the long run.

“Paulit-ulit na lang na nagre-repair tayo ng mga nasira pagkatapos ng pag-uulan, hindi pwedeng ganun (We repeatedly repair damaged infrastructure after the rains; that can no longer be the case),” he said.

Dizon said the department has included funds for modern technologies in its 2027 budget.

For quick response funds (QRF) to address the damage that has reached about PHP3 billion in the Cordillera region, he said they will use new technologies in mountainous areas to ensure that repaired infrastructure lasts for years.

During his inspection at the Benguet-Vizcaya Road along Beckel in La Trinidad, Benguet, where a road slip occurred, Dizon said the slope protection will be installed with a 75-meter-long double-crib wall with a mechanical stability system, estimated to take about 11 months.

The project is allotted PHP75 million in QRF in next year’s budget.

During his visit to the damaged “curtain wall” in Daclan, Tublay, Dizon said the DPWH has already consulted with the Japanese partners that installed the metal curtain wall technology.

“We asked for their help to reinstall the same, replacing only the damaged portion,” he said, noting that the curtain wall did its function of catching debris, leaving the road safe.

He said the Japanese experts have committed to making corrections to strengthen the curtain wall further.

He said that shotcrete slope protection will be done at the upper portion of the mountain to hold the soil and rocks.

Shotcrete slope protection is a construction method in which a concrete mixture is sprayed at high velocity through a hose onto rock or soil surfaces. It seals unstable earth or fractured rock, prevents rain and wind erosion, and stops landslides or rockfalls along roads, hillsides, and excavations.

“The order time will take two months, and it will only be then that we can start the repair using (a) PHP30 million budget. It might take about four months,” he said when interviewed at the site.

At the strawberry farm, which has suffered persistent flooding for more than 20 years, Dizon said that short- and long-term plans will commence immediately.

He said dredging will be done along Bolo Creek and the Balili River where water from the farm’s canals drains. They will also install a floodgate at Bolo Creek to prevent backflow when the creek swells.

As a long-term solution, a huge drainage canal and various water catchment areas will be constructed at the strawberry farm road leading to the Balili River.

During the meeting with the Cordillera Regional Development Council, attended by Baguio and Benguet officials on Friday morning, the DPWH also presented several technologies based on the Japan International Cooperation Agency’s (JICA) recommendation, which had been proven effective in Japan’s mountain slopes.

Presidential Adviser for Cordillera, Assistant Secretary Antonio Tabora Jr. also suggested looking into tunneling as an alternative to the continuous repairs of mountain roads, particularly Kennon Road.

"It is being done in Korea, Japan. Look into it, and if the cost will give us many years without problems and with lesser maintenance cost, then maybe we can consider it not just for Cordillera but in other mountainous areas,” he said.