Nam Ngum 3 and 4 hydropower projects (Laos)

A very significant contribution to boosting renewable energy production in Laos

As part of the country’s ambitious program to increase hydropower production, the Nam Ngum 3 (480 MW capacity) and Nam Ngum 4 (240 MW capacity) projects exploit the potential of a affluent of the Mekong River.

It’s a large-scale project (30 km of hydraulic tunnels, 130 km of high-voltage lines, etc.), and technically very demanding. At 210 m high, the Nam Ngum 3 dam is one of the highest in the world.


With an estimated hydroelectric production potential of 26.5 GW, the Democratic Republic of Laos is considered by the IHA (International Hydropower Association) to be one of the countries with the largest resources in South-East Asia, due in particular to the presence within its territory of a large part of the Mekong basin. In 2022, installed capacity reached 8,108 MW and annual national production 21 TWh.

Since 1993, several hydroelectric development programmes have been initiated, stimulated by the possibility of exporting the electricity produced to neighbouring countries (Thailand, Vietnam, Cambodia). Artelia played a part in this boom, notably with the construction of Nam Leuk, one of the country’s first major hydroelectric schemes (60 MW, commissioned in 2000). The Nam Ngum 3 and 4 projects are part of this development and represent a new stage in it.

Our teams are proud to be contributing to this achievement. It is an exciting technical challenge, given the extraordinary dimensions of the Nam Ngum 3 facilities and the complex geological environment in which they are located. It is also a major human adventure for the thirty specialists in civil engineering, electromechanical engineering, geotechnical engineering and environmental engineering who are working for Artelia in France and Laos to ensure the success of these two projects.