MANILA - Five dams in northern and central Luzon were continuing to spill water as of Friday noon due to heavy rains dumped by “Pepeng.”

However, authorities have started to gradually decrease the spilling volumes, according to an official of the state weather agency,

Susan Espinueva, officer-in-charge of the Hydrometeorological Division of Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), told ABS-CBN News Channel on Friday that the dams – Ambuklao, Binga, San Roque, Magat and Pantabangan – were continuing to spill water as of noon Friday.

However, with less rain pouring on the mountainous areas of northern Luzon on Friday and less volume of water flowing to the dam reservoirs from upstream sources, the dams have started to gradually decrease the spilling discharges.

San Roque dam, which started releasing its excess water from its reservoir on Thursday, greatly affected the rise of floodwaters in areas of Pangasinan.

PAGASA Administrator Prisco Nilo told ABS-CBN's Umagang Kay Ganda that as of 3 a.m. the dam was releasing water at a rate of 5,361 cubic meters per seconds (cms). By 8 a.m., it was reported to be releasing water at the rate of 3, 800 cms.

As of noon Friday, San Roque dam was only discharging water at 2,000 cms. By 2 p.m., the dam further reduced its rate of discharge to 1,671 cms.

Espinueva said the same was also being done in Ambuklao and Binga dams after the weather improved Friday morning as “Pepeng” moved westward. The outflows of the two dams also go to San Roque dam, she said.

PAGASA, according to data posted in its Web site 2 p.m. Friday, showed that Ambuklao was spilling water at the rate of 686 cms; Binga at 1,277 cms; Pantabangan at 600 cms; and, Magat at 1,687 cms.

Only San Roque dam and Magat were above the normal elevation of their respective water reservoir levels with the others just slightly below.

Still critical

Espinueva, however, admitted that the reservoir water level of San Roque dam was still critical, and that it will take several days to lower water elevation of the dam.

She said they will still gradually decrease the outflow of San Roque dam since less water is going to the reservoir compared to the previous days. This will also reduce the flow of water to already inundated areas of Pangasinan.

“We don't want to add to the height of the water level downstream,” said Espinueva.

After the floods subside, she said only then will they consider intensifying the release of water from the dam's reservoir.

90% flooded

Pangasinan Governor Amado Espino Jr. said that as of 2 a.m. Friday, there were already 30,000 people in evacuation centers in higher areas of the province. He said thousands more, particularly those living in the eastern part of the province, are trapped on the roof of their houses.

Provincial officials said almost 90 percent of the province or 30 towns and cities were already submerged in critical levels of floodwaters.

Baraan said municipalities in more critical situations were Umingan, Tayug, San Nicolas, Natividad, Sta. Maria, San Manuel, Balungao, Rosales, Bautista, and Bayambang in eastern Pangasinan.

He said people in the central towns of the province -- San Fabian, Mangaldan, San Jacinto, Calasiao, Sta. Barbara, Manaoag -- are also in danger of being overwhelmed by floodwaters.

PAGASA earlier said it expects Pepeng's rains to ease as it moves away from the country.