By HENRY EMPEÑO | August 11, 2026

BOTOLAN, Zambales — Zambales officials are closely monitoring major river systems containing massive lahar deposits following week-long heavy rains that swelled waterways and inundated floodplains in several municipalities in the province.

Governor Hermogenes Ebdane Jr. on Monday, August 10, ordered the preemptive evacuation of residents in Barangay San Juan, Botolan, Zambales after inspecting a collapsed portion of a dike that shields at least six barangays from the lahar-filled Bucao River here.

“As of now, we are dropping armor rocks into the scoured portion and doing sandbagging to strengthen the dike foundation and prevent a total breach,” Ebdane said on Monday.

“We’re doing all we can to prevent a dire situation like that in 2009 when the earth dike along Bucao gave way and caused a major disaster in Botolan. We don’t want that to happen again,” Ebdane said.

According to Engr. Domingo Mariano, the provincial consultant on infrastructure development, the barangays of San Juan, Paudpod, Carael, Bangan, Capayawan, and Batonlapoc could be flooded should the Bucao River Dike burst due to prolonged pressure from the swollen river.

These villages are directly on the path of the Bucao River and bore the brunt of the massive flooding in 2009, Mariano pointed out.

Aside from Bucao River, Mariano said all eyes are now onto the Sto. Tomas River bordering San Marcelino, San Felipe and San Narciso towns in southern Zambales, after strong current washed out a bridge in Barangay Sta. Fe, San Marcelino on Sunday, August 9, and isolated the upland barangay.

At least 15 barangays in the three adjoining municipalities are located along the Sto. Tomas River, which drains directly from the foothills of Mount Pinatubo.

Ebdane said the lahar from the 1991 volcanic eruption continues to be a major threat to Zambales communities during the rainy season when heavy downpour dislodges massive deposits upstream and send them cascading downriver.

The Mines and Geosciences Bureau (MGB) in Central Luzon estimated that 6.7 billion cubic meters of volcanic debris remain on the Zambales side of Pinatubo, with 3 billion cubic meters, or 63.8 percent of river-bound lahar, in the Bucao River basin, and 1.6 billion cubic meters in the Sto- Tomas River basis.

Mariano said the provincial government has been actively undertaking dredging of the Bucao and Sto. Tomas rivers under the Zambales River Restoration Program since 2023, but had so far only cleared the river deltas due to the huge volume of lahar sand in the waterways.

Heavy rains from habagat or the southwest monsoon and the recent typhoons that entered the country also brought more lahar downriver and temporarily stopped dredging operations, Mariano added.

Meanwhile, the Zambales Provincial Disaster Risk Reduction and Management Office (PDRRMO) said in an initial report that six infrastructure facilities in the province were damaged during heavy habagat rains induced by the Typhoons “Luis” and “Maymay” starting last week.

The Sta. Fe Bridge in San Marcelino town, which was swept away by strong river current, and a Small Water Impounding Project in Barangay Amungan, Iba worth P700,000, were totally destroyed, it said.

The PDRRMO also listed four partially damaged structures: a multi-purpose hall in San Miguel, San Antonio; the Tanguay Slope Protection in Sto. Niño, Cabangan; another slope protection project in Bayto, Sta. Cruz; and the San Juan Dike in Botolan town.

PDRRMO head Rolex Estella also said that as of 5:00 p.m. on Monday, August 10, a total of 7,044 individuals, or 2,441 families, have evacuated their homes due to rising floodwaters across the province.

Of these, a total of 4,706 persons, or 1,621 families, remained in evacuation centers while 102 families composed of 285 individuals sought shelter with relatives, Estella said. ▲

COVER PHOTO: Gov. Hermogenes Ebdane Jr. (left) and Engr. Domingo Mariano inspect the eroded portion of the Bucao River Dike in Botolan, Zambales on Monday, August 10. (ZFTP photo)