Disaster officials and public were warned to brace for dangerous mudflows from Mayon volcano following heavy rainfall caused by the tail end of the cold spell, The Manila Times Online reported on Sunday.
Ed Laguerta, resident chief of the Philippine Institute of Volcanology and Seismology (Phivolcs), said that all river channels connected to Mayon gullies were more dangerous than ash fall and could become conduits for lahar flow in low-lying areas of Albay province.
Lahar from restive volcano is soft but dangerous and could tumble down big boulders ejected by Mayon.
In the past 15 days of occasional eruptions, at least 25 million cubic metres of volcanic debris, 10.5 million cms of which are lahar materials.
Local officials reported of a flow of grayish to black water cascading in Bulawan river in Malilipot some 23-25 kilometres away from Legazpi City.
Several river channels from the slopes of Mayon are now swollen following heavy rainfall, prompting disaster officials to enforce evacuation of residents living along the riverbanks.
Albay governor Al Francis Bichara on Saturday summoned municipal mayors from affected towns for an urgent meeting and told them to immediately carry out forced evacuation of residents.
Total volume of lahar deposited on the watershed was approsimately 9 million cubic metres, excluding unverified deposits on the northern flank. The ashfall on the western sector was roughly 1.5 million cubic metres.
About 80,000 people are already housed in evacuation centres.