A Mines and Geosciences Bureau official on Wednesday encouraged local government units to have their own rain monitoring gauges for them to apply the necessary measures to protect their constituents from landslides and flooding.
Guillermo Molina Jr., chief science research specialist of MGB Region V, told GMA News the areas where landslides happened in the aftermath of Tropical Depression “Usman” have already been identified as landslide-prone, and most of them have ongoing road construction.
“LGUs should have separate rain monitoring per watershed. They should know how to use these rain gauges and create measures for appropriate evacuation procedures in case warnings like this are raised,” he added.
At present, the Bicol region only has five rainfall collecting stations, which may give different results compare to what is happening in other areas, Molina told GMA News TV program “Balitanghali.”
“It’s hard to predict rainfall with too few gauges. For example, here in Legazpi City, we recorded 462 millimeters [rainfall] for two days, but the record is different in Daet, in Sorsogon, in Pili, or at the Sangay area. Conditions are different there,” he said.
The MGB official said the rainfall monitoring system would complement the data given to LGUs.
Areas the bureau identified as technically hazardous saw their risks magnified with the changing weather conditions, “but these information were already given to the LGUs,” Molina said.
“[The roads] had ratings of moderately [prone to landslides] to high. If you will observe, most landslides happened near road openings, like in Sorsogon City where a road was being built near the sea,” Molina said.
“The same thing [happens here in] Tiwi, Albay. We cut a road through a mountain. Beneath that is the sea, and that road network leads to Sangay [town], to barangay Patutian in Sangay, where several landslides happened,” he added.
The soil condition in the region was worsened by the high amount of rainfall, Molina said.
“Legazpi City, in a matter of two days, had record rainfall for December ng Legazpi, and it rained on 88 percent of the city, a total of 462 millimeters rainfall in a matter of two days, December 28 and 29,” he said.
Local officials did not order forced evacuation because the state weather bureau had downgraded the typhoon warning signal, Molina noted, adding this should prompt LGUs to have their own rain monitoring system.
“People know what to do for typhoon signals 1 to 4, but [weather bureau] Pagasa only issued a yellow rainfall warning,” the MGB official said. “The typhoon warning dropped on Dec. 29, but the rains still fell hard, when most of the landslides happened.”
MGB teams are now going to areas affected by landslides such as in Sorsogon City; Bulan, Sorsogon; San Francisco, Legazpi; and Tiwi, Albay.
Latest data from the National Disaster Risk Reduction and Management Council showed 85 people have been reported dead due to the onslaught of “Usman.”