Pilot projects to strengthen sustainable management of the Cambodia–Mekong Delta Aquifer

Over 50 participants gathered in Hanoi in July to take the first steps for pilot projects that seek to turn scientific evidence into practical solutions for the Cambodia Mekong Delta Aquifer. The meeting was part of the “Enhancing sustainability of the Transboundary Cambodia–Mekong River Delta aquifer” (CMDA) project, a transboundary aquifer initiative implemented by the Food and Agriculture Organization of the United Nations (FAO) and executed by IUCN, UNESCO, MERFI and the governments of Cambodia and Viet Nam.

26 Aug 2026

The Cambodia-Mekong Delta continues to face groundwater depletion, declining groundwater levels, salinity intrusion and land subsidence. The proposed pilots from the two countries are different in focus but share a common goal to turn scientific evidence and technical recommendations into practical solutions on the ground. Joint Technical Committee representatives from Cambodia and Viet Nam, along with representatives from the Department of Water Resources Management (DWRM) under Viet Nam's Ministry of Agriculture and Environment (MAE), the General Department of Environment Protection (GDEP) under Cambodia's Ministry of Environment (MOE), UNESCO, the Mekong Region Futures Institute (MERFI), and other partner organisations also contributed to the pilot planning.

The two countries are exploring different demonstration approaches to address shared groundwater challenges: Viet Nam is considering a transboundary information/data-sharing mechanism, while Cambodia is developing concepts around managed aquifer recharge/groundwater quality and groundwater-dependent ecosystems.

Viet Nam presented a proposed pilot on a transboundary groundwater information and data-sharing mechanism, responding to the lack of an integrated system for sharing groundwater information between the two countries. The proposed pilot aims to strengthen groundwater monitoring and early warning, support better-informed decision-making, and improve technical cooperation.

Cambodia presented two preliminary pilot concepts. The first focuses on managed aquifer recharge and groundwater quality protection in Prey Veng and Svay Rieng Provinces, where communities rely heavily on shallow groundwater. The areas face declining groundwater levels, alongside risks from arsenic and agrochemical contamination. The pilot would test practical, community-based solutions, including recharge ponds and infiltration basins, groundwater monitoring, groundwater quality protection zones, and training on MAR, arsenic filtration and community groundwater management.

The second concept focuses on groundwater-dependent wetlands in Takeo, Kampot and the Tonle Sap region that support biodiversity, fisheries, agriculture and local livelihoods. It would aim to strengthen wetland protection and community resilience through measures such as groundwater protection zones, improved groundwater monitoring and regulation, climate-resilient livelihoods, and community-based fisheries management.

The proposed pilots and concepts remain under development and will undergo further technical review, consultation and refinement before final selection and approval. The initiatives will provide opportunities to test practical approaches, generate evidence and strengthen cooperation in managing the shared aquifer. As the pilot concepts move through technical review and selection, they serve as an important step in addressing CMDA challenges to ensure the aquifer provides vital and sustainable water resources for the region’s communities today and in the future.

The CMDA project is the largest transboundary aquifer initiative in Southeast Asia under the Global Environment Facility International Waters (GEF IW) Focal Area. Implemented over five years (2023–2028), the project is implemented by the Food and Agriculture Organization of the United Nations (FAO) and executed by IUCN, UNESCO, MERFI and the Governments of Cambodia and Viet Nam, through their respective national focal agencies: DWRM under Viet Nam's MAE and the GDEP under Cambodia's MOE.

The project aims to enhance environmental sustainability and water security in the Lower Mekong region by improving the governance and promoting the sustainable management and use of the Cambodia–Mekong Delta transboundary aquifer with five components (1) Conduct a Transboundary Diagnostic Analysis (TDA); (2) Pilot demonstration; (3) Transboundary cooperation mechanism; (4) Develop a Strategic Action Plan (SAP); and (5) Establish mechanisms for monitoring, gender mainstreaming, and transboundary coordination to ensure the project's long-term sustainability.