Source: Ellalyn B. De Vera & Raymund F. Antonio | mb.com.ph
November 9, 2010, 6:21pm
MANILA, Philippines — The Philippine Institute of Volcanology and Seismology (Phivolcs) warned residents near Mt. Bulusan in Sorsogon on the impending threat of rain-triggered avalanche of steaming lahar that may cascade down surrounding communities as mudflows has already shut down Daang Maharlika Highway in Bicol.
“People residing near valleys and streams are advised to be vigilant against sediment-laden stream flows in the event of heavy and continuous rainfall,” it said.
With Daang Maharlika Highway now rendered impassable, the Department of Public Works and Highways (DPWH) advised motorists to take alternate routes.
In a traffic advisory, travelers going to and from Manila to Matnog are told to take the East Coast Road from Abuyog to Gubat Barcelona Road, Bulusan to Irosin, and Irosin to Matnog Roads.
Those plying the route from Bulan, Sorsogon have to take the West Coast Road from Bulusan to Magallanes Road, Magallanes to Juban, and Juban Sorsogon Roads.
In case of massive ash fall, DPWH said the Buklusan to Barcelona Gubat and Gubat to Abuyog Roads will be opened to traffic in the event that the Irosin Section becomes impassable.
Bernie de Leon of the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said isolated rain showers and thunderstorms are expected in Bicol Region, causing rains that may last from 30 minutes to about an hour and may trigger lahar avalanche.
The warning was issued as Bulusan showed a brief respite from ash explosions on Tuesday. However, state volcanologists also warned surrounding communities against minor eruptions that could still occur in the approaching days.
Phivolcs detected a total of eight volcanic earthquakes on Tuesday, down from 28 tremors last Tuesday.
Although the summit of the volcano was most of the time obscured by thick clouds, during times of good visibility, weak to moderate emission of white steam was observed.
Volcanologist July Sabit said “more minor ash explosions may still take place, similar to the November 6 and 8 explosions,” where ash cloud and steam spews were detected.
Sabit said ash explosions are typical of Bulusan Volcano’s activity during its restive period.
Due to the prevailing wind, residents located in the northwest and southwest sectors of the volcano are advised to take precautions against ash falls.
Likewise, Phivolcs advised civil aviation authorities to avoid flying close to the volcano’s summit as ejected ash and volcanic fragments from sudden explosions may pose hazards to aircrafts.
Phivolcs said Alert Level 1 is still observed to reflect the present activity at Bulusan.
The alert warns the public against entering the four-kilometer Permanent Danger Zone (PDZ) from the volcano’s summit.
“The public is strongly advised not to venture inside this area because it may be affected by sudden steam explosions,” it said.
Meanwhile, the National Disaster Risk Reduction and Management Council (NDRRMC) said the government is doing all necessary preparations for possible evacuation of residents near Mt. Bulusan “as more explosions are expected to occur in view of the volcano’s recent reactivation.”
NDRRMC Executive Director and Office of Civil Defense (OCD) Administrator Benito Ramos said residents in the area have already prepared for possible evacuation after the volcano spewed ash and steam on Saturday.
OCD Region 5 Director Rafael Alejandro said no evacuation is being undertaken so far, saying: “We are still on Alert Level 1.” Alejandro said evacuation is usually done when the alert level is raised to No. 3.