Global Environmental Facility (GEF) launches 15 million USD project to boost support on the Mekong Delta’s groundwater system In early June the GEF International Waters Fund has confirmed 15 million USD of new funds to boost efforts in support of Mekong Delta Aquifer.

It aims at improving the Delta’s groundwater system that is severely overexploited due to high demand for water resources from the rapidly increasing population and rapid economic development. The lower section of the Mekong River Basin is underlain by a major transboundary aquifer system shared by Cambodia and Viet Nam.

This Transboundary Aquifer System (TBA) connects two ecosystems of global environmental significance and socio-economic importance: the i) Tonle Sap area and the ii) Mekong Delta, and includes some major urban areas, including Phnom Penh and Ho Chi Minh city. The whole area is approximately 200 000 km2 with about 63 per cent lying within Cambodian territory. Tonle Sap, the largest lake in the Peninsular Indochina, is hydraulically connected to the Mekong River and serves as a natural regulating reservoir ensuring adequate groundwater recharge to the aquifer.

Groundwater is critical for rice production and makes a substantial contribution to the national GDP of Viet Nam. For these reasons, the aquifer is heavily exploited for irrigation and water supply. The annual groundwater extraction rate throughout the TBA is estimated to be about 800–900 million m3/year.

Viet Nam’s Governments are well aware of the various facets of groundwater related problems and have invested in improving the hydrological aspects of the Mekong Delta aquifer. Currently, the main focus lies with adjusting development plans to mitigate emerging risks related to land subsidence and the design of more effective regulatory mechanisms to curb groundwater extraction. The cooperative management of this TBA system is of particular importance because the Mekong Delta and its upstream area are considered as a region with high economic dependence on water resources, and high exposure to climate-related risks (floods and droughts).

For Viet Nam, the security of water resources in the delta area cannot be achieved without a proper understanding of the regional groundwater flow regimes, especially with regard to the up-gradient recharge zones within the Cambodian territory. One of the project’s main objectives is to establish cooperative management frameworks for this major transboundary aquifer embracing the whole Mekong delta and extending upstream in Cambodia. This is of critical importance because of the region’s high dependence on water resources, and vulnerability to climate-related hazards (floods and droughts, sea level rise).

The project will also begin to address gaps in data and knowledge and promote a proper and shared understanding of the regional groundwater flow regimes, especially with regard to the up-gradient recharge zones within the Cambodian territory. 

The project will also support the spirit of the Cambodian and Vietnamese agreement on improving transboundary water management under the Mekong Agreement signed in 1995. The Mekong River Commission will be brought into this process to ensure a potential pathway for institutionalizing solutions for improving the joint management of the Mekong Delta aquifer. The work proposed in this project will be fully-aligned with the ongoing planning process in both countries, in particular the Mekong Delta Development plan and the Prime Minister Resolution 120, and the urban development plans for the wider Ho Chi Minh City area. This project will also contribute to both countries’ Green Growth Strategy, which connect to a wide range of line ministries and will support the achievement of several SDGs (directly and indirectly) and their associated targets.

In Viet Nam, this project will be implemented under the leadership of Ministry of Natural Resources and Environment with the cooperation with the Ministry of Agriculture and Rural Development, Institute of Meteorology, Hydrology, and Climate Change, Department of Southeast Asian - South Asian - South Pacific Affairs - Ministry of Foreign Affairs, as well as other development partners in the sector as relevant.