MANILA, Philippines — The Philippine Institute of Volcanology and Seismology (Phivolcs) yesterday warned of muddy streamflows and lahar in Albay amid the rains brought by the shear line.
Phivolcs cited a Philippine Atmospheric, Geophysical and Astronomical Services Administration report that the shear line is affecting Southern Luzon and predicted to cause a continued severe intensity and potentially high-volume rainfall over the province.
“This can generate volcanic sediment flows or lahars, muddy streamflows or muddy run-off in rivers and drainage areas on the monitored active volcano Mayon,” Phivolcs said.
State volcanologists cited the need for increased vigilance and readiness of communities in pre-determined zones, adding that the bulk of erodible pyroclastic density deposits occupy the watershed areas of the Miisi, Mabinit, Buyuan and Basud Channels.
They warned that lahars can threaten the communities downstream.
Phivolcs also warned that potential lahars and sediment-laden streamflows may occur along the Miisi, Binaan, Anoling, Quirangay, Maninila, Masarawag, Muladbucad, Nasisi, Mabinit, Matanag, Basud and Bulawan Channels in Albay.
“Phivolcs strongly advises the communities and local government units of (these) areas to continually monitor the weather conditions and take preemptive response measures for their safety from the ongoing shear line weather system,” the state agency said.
A prolonged and heavy rainfall, it added, could generate post-eruption lahars on the major channels that drain Mayon Volcano by incorporating loose materials from the January to March 2018 eruption.