“From the Beginning to the End of the Year:
Sediment-starved Mekong and the Algae Bloom”
On 29 October 2019, the Xayaburi dam began its operation. It was also the beginning of unprecedented changes in the Mekong river ecosystems: the sediment-starved Mekong. Between November 2019 and April 2020, the section of the Mekong, downstream of the dam, that forms the 800-km Thai-Lao border between Chiang Khan district in Loei province and Khong Chiam district of Ubon Ratchathani province appeared clear and very low-sediment. At the end of 2020, in November, the sediment-starved Mekong re-emerged. Such a phenomenon has never occurred before the operation of the Xayaburi dam. Fisher folks in all Thai provinces along the Mekong synchronically explained that although the sediment-starved phenomenon happened in the past, it never lasted longer than 2-3 months and it usually only occurred between February and April.
The new phenomenon, the sediment-starved Mekong from the beginning to the end of the year, inserts another layer of impact among the complex impacts created by the operations of large hydropower dams in China, tributary dams and climate change.
The Mekong Butterfly has been monitoring the vagaries of the Mekong river and impacts on the riparian ecosystems and communities along the Mekong mainstream and her tributaries. We have also been monitoring the operations of hydropower projects on the Mekong and their influences on river flows and ecosystems. The report is outlined as follow:
- Mekong ecosystems and the communities that depend on the river
- Changes in the Mekong river flow in 2020
- Impacts of the fluctuating Mekong flow in 2020
- Xayaburi dam: The risks of failed prediction borne by the ecosystems and local communities
- Outlook of the Mekong ecosystems and riparian communities in 2021
Moreover, the Mekong river situation in 2020 has become a part of international conflicts at all scales. It is not only among the four lower Mekong countries but also, specifically, between China and the United States. The situations at the scale of the local community and the sub-ecosystems are already very sensitive and complex. When the Mekong river is pulled into conflicts at multiple scales, as she is now, it would be very challenging for any process to take place to offer tangible solutions to the local communities and the ecosystems.
full report click