Irrigation water suspended starting May 16 as Angat Dam reservoir continues to decline

The National Water Resources Board (NWRB) is suspending the allocation of water for the irrigation requirements of farmlands in Bulacan and Pampanga from Angat Dam starting May 16 to conserve water and reduce the consistent decline in the Angat reservoir.

The allocation for irrigation is currently at 10 cubic meters per second (cms) or 864 million liters per day (MLD) from 35 cms or 3,000 MLD last April.

NWRB Executive Director Sevillo David Jr.

assured that crops will not be affected significantly as cropping season is already near their harvesting period.

Sufficient water for Metro Manila

David allayed public fears that the continuous decline of Angat Dam’s water level could lead to significant water shortage in Metro Manila.

Water allocation for the domestic needs in Metro Manila is still the same at 48 cms or 4,000 MLD.

Citing the Philippine Atmospheric, Geophysical, and Astronomical Services Administration’s (PAGASA’s) near normal rainfall projection between May and July, David said “we think that there is sufficient water for Metro Manila until the onset of the rainy season.”

Based on latest inflow/outflow data using projected PAGASA rainfall in the Angat Watershed, elevation by May 15 may be at 174.48 m, and 172.80 m by end of May upon suspension of water releases for irrigation, David said.

As of 6 a.m. Saturday, water elevation at Angat Dam was 177.03 meters, around 3 meters below the minimum operating level of 180 meters.

“We are closely monitoring the situation for any significant developments,” he added.

Cloud seeding eyed

David said they are also considering cloud-seeding operations over the Angat Watershed by next week.

“Cloud-seeding operation is ready as soon as the conditions are favorable,” he pointed out.

A favorable condition includes the presence of seedable clouds.

Cloud seeding is a weather modification method where chemical “nuclei” such as silver iodide or calcium chloride are introduced in the atmosphere to induce condensation, and eventually, precipitation. Moisture collects around these “nuclei” and fall as rain upon reaching a certain saturation level.

“Other actions to be done to manage the level of Angat Dam include the temporary activation of deep wells and more aggressive water conservation information and education campaign,” he said.