September 2021

13 Sep 2021 - 10:02am

CONTINGENCY PLAN FOR THE MAGAT DAM IN PLACE

September 13, 2021, 10:02 AM
 

NIA Central Office – The National Irrigation Administration (NIA) ensures that it has an existing contingency plan for the Magat Dam located in Municipality of Ramon, Isabela.

On September 01, 2021, a Regional Committee on Dam Safety (RCODS) meeting was held virtually attended by the Cagayan Valley Disaster Risk Reduction and Management Council, Department of Agriculture (DA) Region II, NIA-Region II, NIA-Magat River Integrated Irrigation System (NIA-MARIIS) Philippine Atmospheric Geophysical and Astronomical Administration (PAGASA), Department of Science and Technology (DOST) Region II, Department of Environment and Natural Resources (DENR) Region II, National Housing Authority (NHA) Region II, Isabela State University, and concerned Local Government Units (LGUs). Revised Protocol on Dam Discharge and Flood Warning Operation for Magat Dam was discussed by Acting Head Edwin J. Viernes of the Flood and Forecasting and Instrumentation Section of NIA-MARIIS and a Technical Working Group under the RCODS was directed to be created to review and finalize the project proposal on the Ensemble Technique for Rainfall Runoff Forecasting.

Contrary to the reported that the Office of the Civil Defense (OCD) Region II and the Regional Committee on Dam Safety (RCODS) approved the crafting of the contingency plan proposed by the Provincial Disaster Risk Reduction Management Office (PDRRMO) in case of a possible Magat Dam break during the said virtual conference, NIA-MARIIS assures that it has existing emergency measures for weather phenomena or disturbances, natural disasters, and even manmade disasters that may result to dam breakage.

In fact, the Operation, Maintenance and Safety Manual for the Magat Dam is in place updated since 2007. The first Manual on Magat Operation and Dam Safety was published in 1982 a year before the 1983 official completion of the Magat River Multipurpose Project. To further improve the operation procedures for the Magat Dam especially during occurrences of floods, the PAGASA in cooperation with the NIA and the National Power Corporation (NPC) came out with a Flood Operation Rule for the Magat Dam in April 1992. Ever since, the Magat Dam was operated based on these two Operation Manuals. In 2007, the NIA-MARIIS formed a Committee to review and update the present Dam Operation Manuals. With the support of PAGASA and the assistance and corroboration provided by the SN Aboitiz Power Inc. (SNAP), the Committee came out with the second revision of the Dam Operation, Maintenance and Safety Manual.

Furthermore, instruments and equipment are embedded since the making of the Magat Dam such as Piezometers monitoring pressure beneath or within the embankment pore water pressure, Strong Motion/Accelerograph tracking structure behavior if earthquake occurs and internal stresses, Surface Measuring Points (SMP) surveyed for possible settlement and deformation, and Weirs for checking seepages in the dam embankment. Aside from these, with modernization and technological advancements, new instruments are in place such as Dam Deformation Monitoring System serving as an online monitoring producing data points every 30 minutes for the covered structure. Thus, any abnormalities on the structure will be tracked right away and be acted upon even before a dam break.

According to Acting Manager Carlo C. Ablan of the MARIIS Dam and Reservoir Division, with the Magat Dam’s 39 years in operation, there is still no major deformity or damage on the Magat Dam. 

Recently, during the onslaught of Typhoon Ulysses (Vamco) in Luzon, Cagayan Valley Region was not spared with its widespread flooding. The Magat Dam Protocol on Dam Discharge and Flood Warning Operation was revised after the creation of the Dam Crisis Management Task Force dedicated to review the existing protocols and address concerns on dam management crisis following the flooding incident. This move to revise the Magat Dam Protocol on Dam Discharge and Flood Warning Operation is a way to enhance the Manual in accordance with the changing times with the weather changes affecting dam operation procedures, other partner Agencies’ plans, and the increased awareness and participation of the Local Government Units (LGUs), private organizations and other stakeholders on the impact of the Magat Dam.

The MARIIS Dam and Reservoir Division is strengthening the construction of sediment catchment structures upstream of Magat Reservoir to inject short term solutions for the sedimentation deposition in the reservoir. 27 sediment catchment structures are already in place for sediments not to go down in the reservoir. Aside from that, reforestation in the Magat Watershed is being done since 2014. These are alternative interventions for mitigation prior to a conduct of a feasibility study of the proposed dredging activities at the Magat Dam Reservoir to ensure the structural stability of the Magat Dam and increase the reservoir capacity for irrigation, power generation and flood control.

NIA Administrator Ricardo R. Visaya assures that as the Agency commits to its mandate to manage and maintain irrigation systems, is always ready to support and cooperate with other government agencies in disaster risk mitigation and crisis management.

The 39-year old Magat Dam located in Municipality of Ramon, Isabela

Completed sediment catchment structure at Diadi, Nueva Vizcaya

Completed sediment catchment structure at Diadi, Nueva Vizcaya

Hole digging and staking for reforestation efforts at Magat Watershed

Out-planting and fertilization for reforestation efforts at Magat Watershed

 

**For questions and/or clarifications, you may contact:

EDEN VICTORIA C. SELVA
Acting Department Manager
NIA Public Affairs and Information Staff
E-mail: evcselva2000@yahoo.com
Landline: (02) 8921-3741