I recently had the chance to visit the site of the Lower Sesan 2 Dam (LS2), which is in an early stage of construction on the Sesan River in Stung Treng province’s Sesan district. LS2 would be the first large hydropower dam built in the Mekong River Basin in Cambodia. The project is being developed by Chinese state-owned enterprise Hydrolancang, along with the Royal Group of Cambodia.
While the cost, capacity and design of the dam remain unclear, the project is highly controversial. It would block two of the Mekong River’s largest tributaries – the Sesan and Srepok rivers – creating a large reservoir that would force a number of villages to relocate. The vast majority of villagers in northeastern Cambodia oppose the dam.
Much of the attention of the media and nongovernment organisations in Cambodia has been on the villages that will be flooded by LS2’s reservoir, as well as on the logging activities associated with the project’s reservoir area, but not always within it. The people of these villages have been vocal in their opposition to the project, criticising the meagre compensation offered to them and the poor quality of the relocation sites. But it is important to also focus on the areas beyond the dam’s reservoir and to consider the many tens of thousands of people who will be affected by LS2, upstream and downstream.
When the original LS2 environmental and social impact assessment was prepared in 2008, the authors acknowledged that the dam would have a devastating effect on fish and fisheries in areas far beyond the planned reservoir.
They pointed out that impacts on migratory fish would extend to the Mekong River and Tonle Sap lake in Cambodia, as well as to the parts of the Mekong River Basin in neighbouring Vietnam, Laos and Thailand.
That same year, I conducted a study on LS2 for the Rivers Coalition of Cambodia (RCC). Released in 2009, the study, titled Best Practices in Compensation and Resettlement for Large Dams: The Case of the Planned Lower Sesan 2 Hydropower Project in Northeastern Cambodia, estimated that almost 80,000 people living in 175 villages in Cambodia’s Sesan and Srepok river basins would lose a large portion of their fish catches due to the dam blocking important fish migrations between the Mekong River and Tonle Sap lake and the Sesan and Srepok rivers.
Dramatic changes in water quality and river hydrology, and the associated impacts on aquatic ecosystems and biodiversity, would devastate over 20,000 people living in 19 villages situated along the Sesan and Sekong rivers directly below the dam in Stung Treng province, according to the study. And, ultimately, the loss in fisheries would impact hundreds of thousands of people living along the Mekong River and other Mekong tributaries.
The nutritional impact on the people living in the Mekong River Basin would be significant.
In 2012, an article was published in the Proceedings of the National Academy of Sciences by Guy Ziv and colleagues that examined 78 planned tributary dams in the Mekong River Basin. It estimated that, of all these projects, LS2 would have the most serious impacts on fish and fisheries, possibly leading to a whopping 9.3 per cent decline in fish biomass throughout the Mekong River Basin. The authors concluded that “the construction of the LS2 dam is highly detrimental according to this analysis”.
Given these predicted impacts, it is shocking how little attention the media and NGOs in Cambodia have paid to the potential effects of the project outside of the dam’s reservoir area.
Unfortunately, this situation has played right into the hands of the developers. Though they acknowledge that they will have to compensate those forced to relocate, they are not offering any compensation to people located upstream or downstream of the reservoir area. Those living outside of the reservoir have never been visited by the developers or government officials, and NGOs have also paid insufficient attention to their plight.
This was clear in July when I visited two communes, Phluk and Khamphun, located just downstream from where LS2 is being constructed. Leaders in both communes told me that they still have heard nothing about compensation in relation to the heavy impacts that they will certainly face if the dam is built across the Sesan River. They also reported that neither the Cambodian government nor the media nor NGOs have paid much attention to them in relation to downstream impacts.
There is an urgent need to address the wider effects of LS2’s construction. While those located within the project’s reservoir area are facing some of the gravest impacts, it is time to seriously look beyond the project’s reservoir area. Under the present circumstances, LS2 is a disaster in the making.
Dr Ian G Baird is a faculty member of the University of Wisconsin-Madison’s Department of Geography.