MGB inspects Naga road cracks, cave-in

CEBU, Philippines - The City Government of Naga requested the Mines and Geosciences Bureau (MGB) 7 to conduct an immediate inspection of the cracks and partial cave-in of a road in the hilly village in Barangay Alpaco.

MGB-7 Regional Director Loreto B. Alburo said it will send anew a team of geologists to check the area after they received the letter, dated February 20, from the City Government of Naga.

Alburo said that based on the initial assessment, the cracks and cave-in of the road may have been due to the heavy rainfall, the type of soil being mostly limestone, the presence of ground cracks which became bigger after the 6.9 magnitude earthquake and aftershocks last February 6.

MGB-7 has classified Barangay Alpaco as highly susceptible to landslide in its August 2011-geohazard assessment. The area is characterized by “steep to very steep slopes, underlain by weak materials and with numerous old or inactive landslides.”

A team of geologists led by Maria Elena S. Lupo and Josephine T. Aleta conducted a landslide assessment and mapping in 2011 consistent with the government’s efforts to reduce the destructive effects and impacts of natural hazards.

Results of the 2011 assessment indicated that Barangay Alpaco has mostly limestone materials characterized as typically porous and poorly bedded which has high absorptive capacity.

 Mapped and assessed in 2011, the team recommended the monitoring of progress of mass movement and report to the MGB or municipal and barangay officials, observe for saturated ground or seeps and sunken or displaced road surfaces, the development of an early warning system and installation of slope protection measure along creeks .

Aside from Barangay Alpaco, five other barangays in Naga City which have been rated as highly vulnerable to landslides are Tagjaguimit, Balirong, Mayana, Naalad, and Cogon.

 Meanwhile, eight barangays with moderate to high landslide susceptibility include Cantao-an, Lutac, Lanas, Bairan, Patag, Jaguimit, Uling, and Tina-an.

 Twenty barangays have moderate to high vulnerability to flooding: Lutac, Lanas, Bairan, Patag, Balirong, Uling, Tina-an, Inayagan, Poblacion North, Pangdan, Tangke, Colon, Mainit, Jaguimit, Tuyan, Naalad, East Poblacion, Central Poblacion, West Poblacion, and Langtad.

 Alburo advised communities who are living near or at the foot of the mountain or riverbanks to be on guard and be cautious at all times. – (FREEMAN)