THE Department of Public Works and Highways (DPWH) has raised the alarm over growing road cracks in Sogod, Southern Leyte province.
The growing cracks, visible within the 200-meter road section in Pancho Villa village in Sogod town, have forced the DPWH to close the road to all types of vehicles since March 15.
The road section forms part of the highway that links Visayas to Mindanao.
“Last week, the crack was only 3 meters. Yesterday, the crack has extended to 8 meters. This is alarming,” Ma. Margarita Junia, chief of DPWH-Southern Leyte district engineering office, said in a mobile phone interview on Friday.
Ground cracks or earth fissures are formed as a result of soil surface tension due to the lowering of the ground surface elevation.
The DPWH is still unsure when to reopen the road as potential major landslides continue to threaten the area after last week’s heavy rains.
Junia said measures are being done to prevent landslides, like putting up barriers, constructing drainage channels to divert the flow of surface water, and installation of weep holes.
These activities are based on the recommendations of the Mines and Geosciences Bureau (MGB).
Preliminary findings of the MGB confirm the presence of active ground movements in tension cracks, ruptured surface, and vertical displacements in the road section in Pancho village.
“There is an ongoing soil exploration to find out the soil strata in the area. We also asked for confirmation from the Philippine Institute of Volcanology and Seismology (Phivolcs) if there is a fault line in the area connected to the Central Leyte Fault,” Junia added.
The assessment within the 200-meter stretch of national road also showed an increase in water discharge and water saturation from springs nearby, which caused changes in groundwater level and an increase in water pressure.
Increase in water seepage from gabions has been observed, especially during continuous rain. Gabions are cages filled with rocks installed in roadsides to prevent soil erosions.
“Every data regarding the status of the area will be essential to properly address the threat of landslide and it will also be important in our restoration of the highway there,” Junia said.
With the road closure, motorists bound for Benit port in Southern Leyte are advised to take the longer Tacloban–Mahaplag–Baybay–Bato–Bontoc–Sogod–Daang Maharlika–Liloan–San Ricardo road route.
Another alternative is the Abuyog-Silago Road. Benit port is the region’s gateway to Mindanao.
“No vehicle is allowed to pass the area as we continue to work on preventing a major landslide and monitor the situation. We are still looking for a solution and the road will remain closed until further notice,” Junia added.
The road section is just six kilometers away from the Agas-Agas Bridge, the country’s tallest bridge. The road stretch has been tagged as highly susceptible to landslides.
The MGB has recently ranked Southern Leyte as the seventh most vulnerable to heavy landslides in the Philippines.
Based on MGB’s geo-hazard mapping and assessment, the province recorded a 78 percent landslide probability. (PNA)