VietNamNet Bridge – When hydropower power plant dams are built in masses on Mekong River, this would not only seriously damage the Vietnamese Mekong Delta, but would also threaten the world’s food security.
It is estimated that some 300 dams, both big and small, would be built on the upper reaches of Mekong River. Of these, 1/3 have been implemented. Scientists have warned that Vietnam’s Mekong Delta, located at the end of the river, would be seriously influenced when the hydropower plants become operational.
So many barriers to water flow
Mekong River runs across China, Myanmar, Thailand, Laos, Cambodia and Vietnam. According to Dr. Chu Thai Hoanh from IWMI, a water resource institute, the hydropower plant dams built in China and Laos would hold back 16 percent of the total water output, or 475 billion cubic meters of water. Therefore, it will be certain that the stream flow and alluvium in the lower section would change.
Besides, Thailand, Laos and Cambodia are also trying to take water from Mekong River to water their 1.8 million hectares of agricultural land.
Dr. Dao Trong Tu, an expert from the Vietnam River Network (VRN), said in 1993-2012, China implemented five big hydropower plant projects, while three other dams are under the construction which would be completed by 2020.
The world’s experts have given warnings about the possible impacts of the development of 12 hydropower plant projects on the main stream of Mekong. If the projects are implemented as planned, this would have very big negative impacts on Vietnam as a rice granary, thus threatening the world’s food security.
Laos, besides Xayaburi dam, is also preparing to build more hydropower plants on Mekong – PakBeng and Don Sahong.
How will the Mekong Delta be?
The Mekong Delta takes shape as a result of a thousand year of silt consolidating of the Mekong River. This is considered the most fertile land area of Vietnam which provides the majority of rice to the nation and for export.
However, the rice granary has been facing big risks from the dams in the upper stream, from sea water level rise and from climate change.
Ky Quang Vinh, Chief Secretariat of the Can Tho City Office for Climate Change Works, affirmed that no research work so far says the building of dams on a river would bring the sustainable development to the region.
A research work by the University of Umea (Sweden) and the World Resources Institute (US), the ecology of the Yangtze River (China) has seriously been affected after the Three Gorges dam was completed.
As noted by the U.S. Geological Survey (USGS), on the Columbia River, after 80 years since the first dam was built, the migratory fish production is almost zero, while the average output in the past was some 20,000 tons.
The research work on the possible environmental impacts of the 12 hydropower plant projects on Mekong released by MRC (Mekong River Commission) has affirmed that if the projects are implemented, Mekong Delta would be seriously hurt.
Especially, MA Nguyen Huu Thien, an independent researcher on the Mekong Delta ecosystem, said that Mekong Delta would face the biggest ever threat in the history, if all the hydropower plant projects are built.
It is estimated that 220,000-440,000 tons of white fish would be lost, worth $500 million - $1 billion. And if the development of the plants goes more rapidly than expected, Vietnam would be no more a food export country by mid of the 21st century.