Concerns raised on Laos’ Don Sahong hydroelectric plant

VietNamNet Bridge – Agricultural officials from 13 provinces in the Mekong Delta expressed their deep concern about Laos’ proposed hydroelectric dam on the Mekong River, saying it would have adverse impacts on the lower section of the river.

Mekong Delta, ecological system, freshwater fish

The Mekong River is a trans-boundary river running through China, Myanmar, Laos, Thailand, Cambodia, and Vietnam (Photo: mothegioi)

They gathered at a conference held in Can Tho City by the Vietnam National Mekong Committee and the Ministry of Agriculture and Rural Development to learn information from a national consultation meeting that examined the possible impacts of the Don Sahong hydropower plant on the Mekong River.

Don Sahong, with a capacity of 260MW, is one of nine hydroelectric plants Laos is planning to build on the Mekong River, which is a trans-boundary river running through China, Myanmar, Laos, Thailand, Cambodia, and Vietnam.

Nguyen Duc Anh, director of the Centre for Supporting the Development in the Mekong river basin, said that with current hydrology conditions, around 4 percent of the total volume of annual water of the Mekong River flows into the Hou Sahong channel, where the dam will be set up.

The construction of the dam is projected to divert up to around 50 percent of the volume into the channel, increasing the sand and mud volume four times which could fill the reservoir up with mud only after six years, Anh added.

Phan Thanh Long, from the Aquaculture Research Institute II, straightforwardly pointed out that the dam would deal a blow to the lower areas of the river like the Mekong Delta, which would face the reduction of the alluvium and fishes, leading to poor quality of agro-products, causing great damages for farmers.

The planned dam for the hydroelectric plant Don Sahong locates in Siphandone area of Champassak province, southern Laos.

At the national consultation meeting held in Hanoi on December 22, experts said

the Don Sahong dam would block the flow on Hou Sahong, thus disrupting the passage of migratory fish, damaging the local biological environment, and affecting the livelihood of locals who depend on Hou Sahong.

They agreed that the dam’s impacts must be considered in all aspects, from fishery and the passage of fish, the community of Irrawaddy dolphins in the Mekong River, water quality, ecological system and mud.

The Mekong River stretches more than 4,800km. It has the second biggest fish output in the world, after the Amazon River.

About 20 percent of the global freshwater fish output, or 2.1 million tonnes, hail from the Lower Mekong Basin (LMB), according to a 2010 report on the Mekong River Commission Strategic Environmental Assessment of Hydropower on the Mekong Mainstream.

Other estimates said the river is home to 1,200 fish species. Notably, Vietnam’s Mekong Delta, where the river flows into the sea, harbours a particular diversity of species, 486, with various sizes from several metres to a few centimetres long.

Fishery resources play a crucial role in ensuring food security in the LMB, including Cambodia, Thailand, Laos, and Vietnam, which have the highest level of per capita freshwater fish consumption.

Around 2 million tonnes of fish and 0.5 million tonnes of other aquatic species are caught in the LMB every year in addition to 2 million tonnes of farmed products.

The Mekong River Commission reported that by 2013, there were at least 77 hydropower projects planned on Mekong River's tributaries and 11 mainstream hydropower projects/dams planned in the LMB, which is home to more than 60 million people.


Mekong Delta, ecological system, freshwater fish