Irrigation water cut as Angat reservoir dips

CITY OF MALOLOS, BULACAN, Philippines — Water elevation at the Angat Dam reservoir was recorded at 174.10 meters above sea level on Wednesday, low enough to show sections of the dam’s surrounding wall of rock and earth.

But the water volume was still sufficient to meet Metro Manila’s daily potable water supply, according to the Bulacan provincial disaster risk reduction management office. The dam supplies 97 percent of Metro Manila’s drinking water needs.

The dam’s lowest level was recorded at 157.57 masl on July 13, 2010.

On Wednesday, the allocation of irrigation water was completely cut to more than 25,000 hectares of rice farms in 17 towns in Bulacan province and four towns in Pampanga province.

Rice crops in most farms in these areas were due for harvesting or had already been harvested by this time.

Harvest

More than 200,000 farmers rely on irrigation water from the dam.

Ildefonso Canquin, president of the Provincial Agriculture and Fishery Council, said the National Irrigation Administration had yet to inspect the farm areas that might still need water for irrigation.

The reservoir level plummets during the dry months, or from March to July, and rises in August and September when replenished by rain. The dam level is at its peak in December.

The 51-year-old Angat Dam can take in as much as 210 to 214 masl during the rainy months. It has been retrofitted and strengthened to withstand the impact of a 7.2-magnitude earthquake.

Critical level

It hits the low level when its reservoir elevation is measured at 180 masl, and the low critical level when it reaches 160 masl.

In 2016, the dam recorded its lowest level at 184.93 masl. In 2017, it was 185.71 masl, and last year, 187.91 masl.

Faustino Reyes, forest guard at the Angat Dam watershed, said he saw portions of the reservoir bed when the water level dropped to 170 masl in 2014.

Angat Dam lies atop the mountains overlooking the towns of Doña Remedios Trinidad and Norzagaray in the Sierra Madre mountains. It helps control floods and generates electricity for Angat Hydro Co., which is owned by beverage giant San Miguel Corp. and Korean Water Co. Inc. —Carmel Reyes-Estrope