Visayas warned of mudslides, floods as 'Agaton' approaches.
Mandaue City, Cebu -- The Department of Environment and Natural Resources (DENR), through the Mines and Geosciences Bureau (MGB) 7, on January 17 warned residents of Eastern and Central Visayas that landslides and flooding could strike their communities as a result of heavy rains that newly formed tropical depression "Agaton" is expected to unleash in the days ahead.
"Agaton" was spotted 140 kilometers northeast of Hinatuan, Surigao del Sur as of 11 a.m. yesterday, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said.
"Agaton," according to PAGASA, will bring moderate to occasionally heavy rains and thunderstorms over Eastern and Central Visayas.
With this development, residents living near rivers and at the foot slopes of mountain were advised to be extra vigilant.
DENR 7 Regional Executive Director Dr. Isabelo R. Montejo issued the warning following heavy rains that resulted in landslides and flooding in some parts of Mindanao affecting thousands of residents.
"Flooding occurs when the level of a body of water rises until it overflows its natural or artificial confines and submerges land in the surrounding area due to intense and prolonged precipitation and other geologic factors," MGB 7 Regional Director Loreto B. Alburo explained.
"Flooding which could rise to few meters could be attributed to the proximity of perennial river creek system, poor drainage facility, inherently low lying area, proximity to coastal area, heavily silted river or creek, and encroachment along natural drainage channels," he said.
Communities should refrain from dumping their garbage in rivers and esteros as this will consequently clog waterways and cause flooding, Montejo said.
Landslides on the other hand, occur when the stability of the slope changes from a stable to an unstable condition. A change in the stability of a slope can be caused by a number of factors, acting together or alone. Among the causes include groundwater pressure, soil erosion, earthquake, volcanic eruptions, deforestation, and blasting among others.
The top DENR 7 official urged local chief executives to prohibit habitation in areas declared as "highly susceptible" to flooding and landslides by the MGB 7 to protect people's lives and to implement forced evacuation if the situation worsens.
Meanwhile, Alburo called on local government officials to seriously monitor areas that have been declared as "highly susceptible" to flooding and landslides.
The MGB has completed the geohazard assessment and mapping of the entire country. It has distributed geohazard maps with a scale of 1:50,000 to all local government units. A more comprehensive map using the scale 1:10:000 has also been distributed.
Alburo issued features that might be noticed prior to major land sliding and these include springs, seeps, or saturated ground in areas that have not typically been wet before; new cracks or unusual bulges in the ground, street pavements or sidewalks.