Vietnam’s Mekong Delta, which has already endured years of water shortages due to upstream dams in China and Laos, now faces yet another threat as Thailand is planning major irrigation projects to retain more water for itself.
In a recent move, Thailand’s National Water Resources Committee has approved in principle two projects to divert water from the Mekong River for agricultural purposes to overcome a water shortfall, Thai media reported.
Suphot Tovichakchaikul, chief of the Department of Water Resources, said that water from the Moei, a Salween tributary bordering Myanmar, could possibly be diverted into the Bhumibol dam in the western province of Tak while water from the Mekong River could be piped to other major dams in the northeastern region.
The government would spend 64 billion baht (US$1.8 billion) on the two projects, Bangkok Post quoted the official as saying. The projects are aimed at supplying water to 480,000 hectares of farm area, mainly in the northeast.
Many Vietnamese and international experts have called for Thailand to reconsider the plan as it would exacerbate dire consequences that the Mekong Delta already suffered from hydropower dams built by China and Laos.
Le Anh Tuan, deputy director of Can Tho-based Institute of Climate Change Research warned that the lowlands in Cambodia and Vietnam will be hit the hardest by Thailand's projects.
There will be serious impacts on biodiversity, sediment levels and underground water, he said.
Pham Hong Giang, chairman of the Vietnam National Commission on Large Dams and Water Resources Development, said Thailand’s plan will likely attract opposition from neighboring countries.
"In 2015, water levels were low and there was no flood. Fish harvests were reduced and million households were effected.
“There is already a shortage of freshwater,” he said.
A commentary published by The Nation last week said that water diversion has always been one of the solutions engineered to tackle drought issues in Thailand.
It said pumping water from the Mekong is complicated because there are six countries that have to share this river.
“Pumping water out of rivers, apart from having an adverse environmental impact, can also trigger conflicts between countries. Also, since river-bank erosion is one of the most serious and immediate threats, few countries go for this option,” the commentary said.
Experts have called for measures from Vietnam to prevent harmful actions on the Mekong upstream part.
Pianporn Deetes, Thailand and Myanmar campaign director at International Rivers, said that Thailand’s plan to divert water from the Mekong basin into its northeast region would create environmental impacts to downstream countries including Vietnam.
“While impacts of the diversion project is still unknown, it is predictable that it will exacerbate problems caused by the existing dams on the Upper Reaches in China, and projects under construction in Laos (Xayaburi and Don Sahong).”
It might be crucial for Vietnam to set up an urgent meeting with Thailand and other Mekong countries to discuss this issue and ensure the sustainability of the Mekong's resources, she said.
Deetes urges Thailand to recognize the importance of the 1995 Mekong Agreement and minimize and mitigate harmful effects that might occur to the environment.
An undated file photo shows work on the Xayaburi dam in Laos. Photo credit: International Rivers
Dao Trong Tu, a consultant of the Vietnam Rivers Network, said that Vietnam is closely monitoring the plan and will discuss it at the Mekong River Committee in March.
Robert Mather, head of Southeast Asia group at the International Union for Conservation of Nature, said that any large scale water diversion should be subject to proper assessment and should be discussed in advance with neighboring countries who might be impacted.
He urged other Mekong countries to ratify the UN Convention on the Non-Navigational Uses of International Watercourses (UNWC) that Vietnam signed in 2014.
“The UNWC would provide a mechanism and clear guidelines for dispute resolution. It would also clarify existing rules and procedures whose vague wording encourages conflicting interpretations that strain relations among the MRC (Mekong River Commission) states, especially over consultations about water infrastructure projects and their downstream impacts,” he said.
“Ratification of the UNWC by Laos, Cambodia and Thailand would not solve all the water-related problems in the basins but it might help reduce tensions by obliging all MRC states to more carefully examine the trade-offs involved and give greater consideration to other alternative solutions to address based on the best criteria available.”