Typhoon 'Juan' seen to fill up Magat Dam


Posted at Oct 16 2010 06:32 PM | Updated as of Oct 17 2010 08:41 PM

Typhoon 'Juan' seen to fill up Magat Dam 1MANILA, Philippines - One out of 4 big dams in Luzon may get filled up by the big amount of rain that super typhoon "Juan" (international name, Megi) is expected to dump, a scientist of weather bureau PAGASA said.

Dr. Susan Espinueva, chief of Philippine Atmospheric, Geophysical & Astronomical Services Administration (PAGASA) hydrometeorological division, said the direction of typhoon Juan indicates that it will affect the Magat Dam watershed in Isabela province.

In a 5 p.m. briefing on Saturday, PAGASA weather forecaster Mario Palafox said the projected track of typhoon Juan shows it will cross the provinces of Cagayan, Apayao, and Ilocos Norte.
The super typhoon, with maximum winds of 140 kilometers per hour (kph) and gustiness of 170 kph, is expected to hit landfall over Cagayan province on Monday morning. It is expected to exit Ilocos Norte Monday afternoon, Palafox said.

It was moving west northwest at 24 kph and was 820 kms. east of northeastern Luzon.

Espinueva said the water level in Magat Dam in Isabela province, as of 4 p.m. of Oct. 16, was 183.41 mm, which means it had a deficit of 3.73 mm.

She added that 120 mm of rain is needed to fill up Magat Dam.  

Given the projected 200 mm of rain that typhoon Juan is expected to bring, Espinueva said this amount will "surely normalize" Magat Dam's water level.

She said PAGASA will announce if it will be releasing water from Magat Dam in case this becomes necessary.

Espinueva indicated that 3 other big dams in Luzon--Angat Dam, Pantabangan Dam, San Roque Dam--are not expected to catch the big amount of rain from typhoon Juan.

As of 4 p.m. of Oct. 16, Angat Dam had a deficit of 11.65 mm; Pantabangan had a deficit of 14.33 mm, San Roque had a deficit of 24.38 mm.

For their respective water levels to normalize, Espinueva said Angat will need 488 mm of rain; Pantabangan will need 270 mm; San Roque will need 1,160 mm of rain.

Palafox said Metro Manila will experience cloudy weather and rains, but the rains will not be due to typhoon Juan.

For more 'Juan' updates, go to the Weather section