The Integrated River Basin Management [IRBM[ Project is one of the flagship regional initiatives under the Association of Southeast Asian Nations [ASEAN] Working Group on Water Resources Management (AWGWRM). It supports the implementation of the ASEAN Strategic Plan of Action on Water Resources Management. The report titled “Proceedings of the Fourth Regional Steering Committee Meeting”, provides an overview of the progress of the IRBM Project across six participating ASEAN member states, including country-level achievements, challenges and planned activities. The latest progress review covers activities undertaken during the reporting period July 2025 to June 2026, with several pilot interventions and technical outputs scheduled for completion or further development during 2026.
The project aims to strengthen integrated river basin management, improve water quality and reduce pollution across the ASEAN region. It also promotes environmental flows and regional co-operation. Additionally, it develops knowledge, technical guidance and practical tools to support river basin management beyond the pilot areas. Its work combines baseline assessments, pilot interventions, knowledge sharing, capacity building and stakeholder engagement. A few edited excerpts…
Cambodia
Cambodia has made progress in assessing pollution sources and developing practical interventions for the Kampong Bay river basin (KBRB). The source-to-sea river basin (SORB) report for the basin has been finalised. A total pollutant loading (TPL) assessment covering agriculture and livestock sources around the KBRB has also been completed. Under the pilot component of the IRBM, Cambodia is developing wastewater and waste management pilots in Kampot, including a centralised treatment plant and decentralised sewage and solid waste treatment. Feasibility studies for both interventions are expected to be completed in 2026. The next phase will prioritise feasibility studies, TPL assessment and stakeholder engagement.
Indonesia
Indonesia has advanced its work on the Ciliwung river basin through baseline assessments, pollution monitoring and pilot project preparation. The draft SORB baseline report for the basin has been completed and is undergoing technical review. A TPL report is also being prepared, with available data compiled and pollution hotspots identified. The assessment examines pollutant loading trends across the basin.
A key pilot intervention is being developed at a nutritional provision service unit in Depok City. Site assessments and technical coordination have identified the need for a wastewater treatment plant and a food waste digester. Planning and design preparations are currently under way. The pilot will demonstrate practical wastewater and food waste management within an operational facility. Indonesia has also strengthened Ciliwung river basin water quality management through the establishment of a basin-wide management plan and river segmentation. Indonesia has continued Ciliwung river restoration with public and private stakeholders. Data gaps persist, prompting a proposed extension to 2028 to complete the Depok pilot.
Lao PDR
Lao PDR has completed the SORB Baseline Report for the Nam Tha river basin following stakeholder consultations and technical review. A rapid TPL assessment has also been conducted to identify major land-based sources of pollution. The findings have been incorporated into the SORB report.
Governance assessments have been undertaken across Luang Namtha, Oudomxay and Bokeo provinces. These assessments support the development of pilot interventions and examine financing and institutional arrangements. Several priority areas include headwater protection and municipal water supply in Paktha district and others around the Nam Hin Reservoir. Lao PDR has also participated in regional IRBM workshops and training programmes. The next phase will include reviewing the 2021-2025 Nam Tha River Basin Management Plan and developing a pilot project concept for launch in 2026.
Malaysia
Malaysia has strengthened the institutional framework for the Kedah River Basin through agreements among Universiti Sains Malaysia (USM), the Department of Irrigation and Drainage, Malaysia, and the Kedah State Water Resources Board. A data workshop with 37 participants supported the compilation of hydrological, water quality, land use and watershed data. Field assessments covering the Pedu Dam, the Muda Agricultural Development Authority irrigation scheme and Kuala Kedah identified monsoon flooding, sedimentation and deteriorating water quality as key priorities for the pilot.
USM has also been identified as Malaysia’s proposed IRBM Learning Centre because of its expertise in river engineering and urban stormwater management. Government restructuring and changes in institutional responsibilities have affected coordination. Malaysia has proposed extending project implementation by one year, to June 2028, to complete the remaining works under the project.
Philippines
The Philippines has completed SORB reports for the Imus-Ylang Ylang-Rio Grande Rivers (IYRR) and the Pasac-Guagua Watershed (PGW). Both reports are undergoing technical review and are targeted for publication in 2026. In the IYRR basin, the Water Quality Management Area Governing Board endorsed the establishment of a septage treatment plant in Amadeo, Cavite, in March 2026. The proposal followed consultations with environmental authorities, public works agencies and other members of the governing board. The feasibility study is being updated to align with the national sewerage and septage management programme.
The Philippines is also updating the 10-year IYRR Water Quality Management Area Action Plan for 2026-2035. Delays in signing the project agreement had reduced the implementation period available for the pilot projects.
Vietnam
Vietnam has completed baseline surveys for the Vu Gia-Thu Bon river basin. Technical outputs under review include the draft SORB report, a rapid pollution load assessment, a biophysical profile, a socio-economic and demographic profile, and a governance and coordination assessment.
Two pilot demonstration sites have been selected in Da Nang. The first is the Duy Nghia Fishing Port, where the proposed activities include waste collection, source segregation and plastic waste reduction. The second is a plastic-free community model along the Truong Giang river. Preparations for a memorandum of understanding and a Korean-funded cooperation proposal are under way, with implementation planned from 2027. The project has also assessed technical assistance requirements for municipal solid waste management. Governance and policy recommendations have been completed, while a draft Pollution Source Control and Water Quality Monitoring Plan is being prepared for the basin.
Regional outlook
Across the six SEA countries, the project is moving from baseline assessments towards practical interventions in wastewater, solid waste, pollution control, water quality and climate resilience. Cambodia and Indonesia are advancing wastewater and waste management pilots, while the Philippines focuses on septage and food waste. Lao PDR is prioritising basin protection and climate-resilient livelihoods, Malaysia is strengthening Kedah river basin governance, and Vietnam is addressing plastic and waste management. Key challenges include data gaps, limited technical capacity and stakeholder participation. The next phase will focus on completing assessments, advancing pilots, strengthening governance and preparing the 2027 regional work plan.
