Jica, DPWH revisit flood-control efforts in M. Manila, Cagayan Valley

THE Philippines and Japan are reviewing their f lood-control projects in Metro Manila and Cagayan Valley to boost their adaptability against the long-term effects of climate variabilities and instabilities.

Master plans and pre-feasibility studies for flood control in two priority river basins—the Pasig-marikina and Cagayan River—will be updated under the new technical-cooperation project between the two countries.

“[Floods are becoming] more frequent and severe due to climate change,” the Japan International Cooperation Agency (Jica) said in a statement. “The updated master-plans…will be a guidepost toward [the achievement of a] 100-year f lood safety even with climate change impact.”

Chief Representative Sakamoto Takema of Japan’s aid agency as well as Department of Public Works and Highways (DPWH) chief Manuel M. Bonoan signed the minutes of their meeting on January 17. Both agencies plan to hold consultations among stakeholders in the two river basins to gather feedback and lessons learned in the past flood-control projects.

Since the 1970s, JICA has been helping the Philippine government control f looding in the metropolis by building revetments and flood walls along riverbanks to prevent erosions, as well as placing movable weirs to control the flow of water during high tides or storms.

The aid agency cited a simulation study when Category-4 Typhoon “Ulysses” (international name Vamco) hit Metro Manila in 2020. It caused the worst flooding in the capital city since Typhoon “Ondoy” (international name Ketsana).

Without the flood-control project, economic losses from flooding in Metro Manila would have been at $1.3 billion, as Jica claimed. The number of affected residents has also been reduced to 30,000, compared to the previously estimated 1 million people.

“Ulysses” pummeled Cagayan Valley hardest, as 24 people lost their lives, and affected 5 million residents. Economic losses were at P5.8 billion in agriculture, infrastructure, and f lood-control projects, according to the National Disaster Coordinating Council.

Earlier estimates by the National Economic and Development Authority have assessed the flood suppression of the 500-kilometer Cagayan River at P130 billion for 30 years.

Jica did not mention the improvements needed to make Pasig-marikina and Cagayan River basins adaptable to withstand more destructive typhoons expected with the progression of climate change.

“This cooperation is vital, especially in times of large-scale flood disasters and emergencies,” Sakamoto said. “It also proves coordination and planning are needed.”