RAMON, ISABELA, Philippines — Local officials in Cagayan and Isabela provinces went on high alert anew and suspended classes on Tuesday in anticipation of the heavy rainfall that would be brought by Typhoon Marce (international name: Yinxing) as it traverses through extreme Northern Luzon.
To ensure the safety of students, classes in private and public schools from kindergarten to Grade 12 were suspended in Tuguegarao City and the Cagayan towns of Lasam, Claveria, Sanchez Mira, Abulug, Baggao, Peñablanca, Solana, Piat, Lal-lo, Ballesteros, Tuao, Aparri, Alcala, Camalaniugan, Amulung, Santa Praxedes, Enrile, Allacapan and Sto. Niño.
Authorities in Cagayan also prepared 21 rubber boats and other floating assets, including ambulances, rescue vehicles, yachts and jet skis, to respond to emergencies, according to Cagayan Provincial Disaster Risk Reduction and Management Office (PDRRMO) chief Ruelie Rapsing.
READ: Typhoon Marce expected to intensify before landfall Thursday
Storm’s path
In Isabela, classes were also suspended in several towns while the City of Ilagan, the provincial capital, enforced a liquor ban to avoid accidents during the typhoon’s onslaught.
A “no swimming, no fishing” order has also been issued by the Isabela PDRRMO.
Marce was last spotted 480 kilometers east of Echague, Isabela moving northwestward at 25 km per hour, packing maximum sustained winds of 130 km/h near the center and gustiness of up to 160 km/h, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) said in a bulletin at 5 p.m. on Tuesday.
It was projected to make landfall or pass close to Babuyan Islands or the northern portion of mainland Cagayan on Thursday afternoon or evening of Friday.
Pagasa on Tuesday placed under Storm Signal Number 1 the provinces of Batanes, Cagayan including Babuyan Islands, Ilocos Norte, Ilocos Sur, Apayao, Abra, Kalinga, Mountain Province, Ifugao, the northern portion of Benguet (Mankayan, Buguias, Kabayan, Bakun, Kibungan, Atok, Bokod), Isabela, Nueva Vizcaya, Quirino and the northern portion of Aurora (Dilasag, Casiguran, Dinalungan, Dipaculao, Baler and Maria Aurora).
Dams’ levels
Marce came at a time when most areas in Luzon, were still reeling from the effects of two successive storms, Severe Tropical Storm Kristine (Trami) that devastated the Bicol region on Oct. 22 and Supertyphoon Leon (Kong-rey) that lashed through Batanes on Oct. 31.
Magat Dam in Isabela was preparing to release water in anticipation of the new typhoon’s heavy rainfall, Angat Dam in Bulacan was hoping to raise the water level of its reservoir that was not filled despite the torrential rains brought by the southwest monsoon and the weather disturbances this year.
The National Irrigation Administration (NIA)-Magat River Integrated Irrigation System, which operates Magat Dam, announced a scheduled floodwater release on Wednesday to maintain a safe water level in anticipation of the impact of Marce.
According to the NIA, it would discharge 133 cubic meters per second due to the expected rise of 1 meter in water height.
Magat Dam’s elevation was recorded at 183.90 meters above sea level as of Tuesday, still below its normal level of 193 masl, with both inflow and outflow measured at 269.94 cubic meters per second.
In Bulacan, the recent typhoons, along with the seasonal rains, have raised water levels at Angat Dam to 202.46 masl but it was still nearly 10 meters below the dam’s normal high water level of 212 masl, which is essential to ensure adequate water supply for irrigation in Central Luzon and the tap water needs of Metro Manila.
Bulacan PDRRMO chief Manuel Lukban Jr. said the heavy rains brought by Typhoon Carina (Gaemi) in July and Kristine last week helped replenish the reservoir, but current levels are still insufficient.
“This elevation remains low, and we need more rains to secure a stable water supply,” Lukban told the Inquirer.
Lydia Cordero, head of the NIA–Irrigation Management Office in Bulacan, echoed these concerns, noting that the current level does not guarantee the capacity to support the irrigation needs of 25,229 hectares of rice farms in the upcoming cropping season.
Prep for dry season
According to Cordero, the elevation of Angat Dam must reach 212 masl to provide a reliable water supply through the dry season starting in December.
To prioritize Metro Manila’s water supply, the NIA, which manages Bustos Dam that relies on Angat, has reduced water allocations for irrigation.
Currently, the NIA releases 25 cubic meters per second of water to serve over 22,000 farmers across 17 towns in Bulacan and four in Pampanga.
After hitting a low of 176 masl on July 21 due to the effects of El Niño, the Angat reservoir experienced a steady rise, reaching 186 masl on July 28 after Carina and climbing further to 202.51 masl following Kristine.
But forecasts by Pagasa suggested that the four to seven typhoons by year-end could potentially bring the dam closer to its ideal level.
Angat Dam, located in Bulacan’s Norzagaray town within the Sierra Madre’s Angat Watershed, serves multiple roles, including providing 97 percent of Metro Manila’s potable water, generating hydroelectric power, supporting flood control and supplying irrigation water to farmlands.
It has yet to release floodwaters this season as its current levels remain below the 212-masl spill threshold.
Ipo Dam, which feeds water from Angat to Metro Manila, reached its 101-masl spill level during recent storms and subsequently ceased releases when Kristine exited the Philippine area of responsibility.
Bustos Dam also briefly released water, reaching 52 cubic meters per second on Nov. 2 before halting discharges early of Nov. 3 as its level stabilized.
The PDRRMO remained hopeful that incoming storms will further increase Angat Dam’s water level, supporting both irrigation and urban water needs.