Ambuklao Dam water level may further rise despite ‘Pepito’ exit

FILE: Ambuklao Dam (upper left), Binga Dam (lower left) and San Roque Dam (right). (Photos courtesy: Napocor and San Roque Dam website via PNA)

MANILA – Water in Ambuklao Dam may rise further, with some possibility of reaching the spilling or normal high level, even if severe tropical storm ‘Pepito’ (international name ‘Saudel’) exited Luzon.

Runoff from previous days’ rainfall that may still occur over the Ambuklao area in Benguet province can help fuel such water rise, noted Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) hydrologist Sheila Schneider.

“We’re not discounting that possibility,” she said.

PAGASA reported Ambuklao Dam’s 6 a.m. water level on Thursday at 746.78 meters, just 5.22 meters below the 752 meter-high spilling level.

According to PAGASA, Pepito was 380 km west of Pangasinan province’s Dagupan City at 3 a.m. Thursday.

Pepito is moving west-northwestwards at 10 kph with maximum sustained winds of 100 kph near its center and gustiness of up to 125 kph.

PAGASA weather forecaster Shiela Reyes said although Pepito will no longer affect Benguet, the northeast wind flow may still bring rain to the area.

“Light to moderate rain is possible in Benguet during the next five days,” she said.

Aside from being below the spilling level, PAGASA data showed Ambuklao Dam’s 6 a.m. water level on Thursday is also 1.72 meters higher than what it was 24 hours earlier.

Rain from Pepito helped raise Ambuklao Dam’s water, Schneider noted. Rise in Ambuklao’s water was 0.95 meter and 0.20 meter only on Oct. 21 and Oct. 20, respectively, PAGASA data showed.

Ambuklao, Binga and San Roque dams comprise the series of dams which support irrigation and power generation in Luzon.

Rains brought about by Pepito facilitated rise of Binga’s water level, which prompted authorities to release water in the afternoon of Oct. 20.

The opening of Binga’s Gate 3 then was 0.50 meter high to accommodate spilling operation with an estimated water discharge of 65 cubic meters per second, noted National Power Corporation (NPC).

Round-the-clock spilling operation continued there on Oct. 21, NPC said. By 8 a.m. Thursday, Binga already lowered its Gate 3 opening to just 0.30 meters.

However, San Roque Dam continued struggling for water despite the onslaught of Pepito.

PAGASA said San Roque’s 6 a.m. water level on Thursday was at 244.96 meters only — 35.04 meters below the normal high level of 280 meters.