The core of this instability lies in the ongoing construction of the Ream National Park hydropower project, a vast dam slated to be built adjacent to Cambodia’s coastline. This project, spearheaded by Thailand with significant Chinese investment, has triggered a fierce response from Vietnam, which contends that the dam will drastically reduce the flow of the Mekong, impacting its own agricultural sector and the livelihoods of millions. Vietnam’s concerns are deeply rooted in historical grievances regarding Mekong water sharing, dating back to the 1960s and 70s, when the river’s flow was diverted during the Vietnam War. This past has fostered a deep-seated distrust, amplified by a perceived lack of transparency from Cambodia regarding the project’s environmental impact and its potential influence on downstream water availability.
Adding further complexity is Laos’s own substantial hydropower development along the Mekong. With China’s encouragement, Laos has aggressively pursued dam projects, diverting massive amounts of water upstream. This action exacerbates the already constrained flows and fuels tensions with Vietnam and, to a lesser extent, Cambodia. “The situation is a classic example of upstream-downstream conflict,” explains Dr. Eleanor Evans, Senior Research Fellow at the Lowy Institute’s Indo-Pacific Programme. “Without robust regional governance mechanisms – something conspicuously absent – the Mekong’s flow becomes a weapon in the strategic calculations of powerful states.”
Cambodia’s position has been primarily one of neutrality, seeking to maintain positive relations with both China and Thailand, while also safeguarding its own economic interests. However, Prime Minister Hun Manet’s recent rhetoric, characterized by accusations against Vietnam of “political interference” and advocating for a “Cambodia-first” approach to water management, has dramatically escalated the situation. This stance is viewed by many analysts as a calculated move to bolster Cambodia’s independent foreign policy and attract continued Chinese support, particularly as China increasingly seeks to counter regional influence.
Data from the Mekong River Commission (MRC), an intergovernmental organization established to manage the Mekong’s resources, shows a consistent decline in the river’s flow over the past several decades, a trend significantly accelerated by the increased dam construction. The MRC’s attempts at collaborative water management have been consistently hampered by the lack of full participation from all member states and, more recently, by Cambodia’s reluctance to engage in meaningful dialogue. According to a report released by the Stockholm International Water Institute (SIWI), “The current trajectory of the Mekong Basin is unsustainable, driven by a combination of ecological pressures and geopolitical competition.”
The broader implications extend beyond Vietnam and Cambodia. China’s growing influence in the region, coupled with the strategic importance of the Mekong Delta to Vietnam’s economy, creates a complex web of interests. Thailand’s dam project is partially driven by China’s desire to strengthen its economic ties with Southeast Asia and its strategic positioning within the region. “The Mekong is becoming a critical flashpoint in the broader Sino-American competition for influence in Southeast Asia,” observes Professor David Shambaugh, a leading expert on Southeast Asian politics at Georgetown University. “Cambodia’s ability to navigate this situation will have profound consequences for the stability of the Indo-Pacific.”
Looking ahead, the next six months will likely see continued tensions, with potential for further diplomatic clashes and increased surveillance of dam construction activities. Negotiations through the MRC are unlikely to yield significant breakthroughs without a fundamental shift in Cambodian policy. Longer-term, the future stability of the Mekong Basin depends on the establishment of a truly independent and effective regional governance framework. This would require not only the participation of all Mekong riparian states but also the willingness of major external powers – particularly China and the United States – to respect the sovereignty of the region and prioritize collaborative water management. The risk of a regional conflict, triggered by escalating tensions over the Mekong’s flow, remains a genuine concern. The murky waters of the Mekong, it seems, are poised to test the resilience of regional alliances and the broader balance of power in the Indo-Pacific.