The Department of Public Works and Highways (DPWH), in partnership with the Japan International Cooperation Agency (JICA), is intensifying its collaborative efforts to finalize the updated flood control master plans for the Pasig-Marikina and Cagayan River Basins—two (2) major waterways in Luzon that play a crucial role in supporting the economic growth and development of Metro Manila and the Cagayan Valley Region.
DPWH Senior Undersecretary Emil K. Sadain and JICA Senior Representative Takanori Morishima led the presentation and discussion on August 5, 2025 of the draft updated Flood Control Master Plan Reports of Pasig-Marikina River and Cagayan River Basins. These plans aim to mitigate the recurring and long-standing problem of widespread flooding while enhancing disaster resilience through both structural and non-structural measures in the affected areas.
Also in attendance during the Second Steering Committee Meeting for the ongoing Project on the Enhancement of Flood Control Strategy in Prioritized River Basins are DPWH Project Director Ramon A. Arriola III of the Unified Project Management Office - Flood Control Management Cluster (UPMO - FCMC) together with Project Managers Jerry A. Fano, Rhodora Dayco, Grecile Christopher Damo; JICA Study Teams; and representatives from various agencies, including Department of Economy, Planning, and Development (DEPDev), Department of Environment and Natural Resources (DENR), Department of Energy (DOE), Department of Finance (DOF), Department of Interior and the Local Government (DILG); Department of Science and Technology (DOST), Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA), National Irrigation Administration (NIA), and Climate Change Commission (CCC).
During the meeting, Senior Undersecretary Sadain emphasized the urgency of completing the master plan reports, citing the devastating impact of past typhoons such as Ondoy in 2009, Super Typhoon Lawin in 2016, Ulysses in 2020, and Carina in 2024, which severely affected vulnerable areas and displaced many families in the National Capital Region, Region 2, and other parts of the country.
“In response to President Ferdinand R. Marcos Jr.’s directive to revise the flood control master plans and expand infrastructures capacity to address increasing flood risks and climate change threats, the DPWH, under the leadership of Secretary Manuel M. Bonoan, sought the assistance of the JICA Study Team to fast-track the completion of the pre-feasibility study of each river basin. These will then be developed into full-blown comprehensive analyses, to emable the timely implementation of the Detailed Engineering Designs (DED)”, said Senior Undersecretary Sadain.
“Once finalized, the updated master plan reports will be submitted to DEPDev for review and approval, with pre-feasibility studies expected to begin in early 2026. These studies and proposed measures in a wholistic approach are anticipated to support integrated water resources management, improve interagency coordination, and enhance the overall risk and reduction efforts in Luzon”, added Senior Undersecretary Sadain.
JICA Senior Representative Morishima reaffirmed JICA’s commitment to the Government of the Philippines (GOP), emphasizing its long-standing friendship and partnership, and reiterated its unwavering support for building resilient and climate-adaptive flood control infrastructure that can withstand the worsening impacts of changing weather patterns.
One of the key topics discussed was the phased implementation of proposed structural countermeasures for the Pasig-Marikina River. Proposed engineering interventions include the construction of two (2) flow-through dams, four (4) retarding basins in San Mateo, Rodriguez, and Quezon City, and river improvement works including dredging under Phases 2 and 3 of the Pasig-Marikina River Channel Improvement Project, a multi-phase project by DPWH, through the technical assistance of JICA.
After experiencing the recent effect of typhoons and other phenomena in terms of flood damages,
it is imperative to consider the importance and necessity of the flood control dams as countermeasure to reduce flooding damage in Metro Manila.
A separate master plan for the San Juan River was also presented, addressing its low river flow capacity due to shallowness that causes serious flooding in parts of Metro Manila. Proposed solutions include dredging and embankment improvements in Manila, San Juan, and Quezon City, an underground retention channel in Quezon City leading to the Pasig River, and an underground spillway from Quezon City to Manila.
These interventions aim to achieve the flood safety level equivalent to a 100-year return period in the Pasig-Marikina river basin, helping address the long-standing effects of severe flooding and strengthen disaster resilience-aligned with the “Bagong Pilipinas” vision of the government.
Subsequently, the draft masterplan report for the Cagayan River Basin was presented by JICA Study Team Leader Takahiro Mishina, proposing to construct four (4) flood control dams, namely: Siffu, Malig, Ilagan, and Cagayan - all traversing the northeastern part of Luzon. It also includes river improvement works and dredging in the Magapit section of the lower Cagayan River.
The Japan-funded technical cooperation program launched in May 2024, is led by DPWH UPMO FCMC and JICA in partnership with CTI Engineering International Co., Ltd., for the Pasig-Marikina River Basin, and consultants Nippon Koei Co., Ltd., Yachiyo Engineering Co., Ltd., and CTI Engineering International Co., Ltd. for the Cagayan River.