What role should large hydropower dams play in future electricity systems? At the UNFCCC COP 26 in November 2021, the International Hydropower Association (IHA) sought to further the industry's role – and access to climate financing – by advocating 'sustainable hydropower' as vital to achieving net zero emissions targets (IHA, 2021). Civil society groups, meanwhile, countered that hydropower should be excluded from UN climate finance mechanisms, citing the industry's human rights and environmental impacts (Declaration, 2021). Four UN Special Rapporteurs issued a joint statement flagging similar concerns (Agudo et al., 2021).

In this dissensus article, I argue that the claimed benefits of 'sustainable hydropower' are rarely seen in practice, especially in the global south where most new large dams have been built (Moran et al., 2018), and that this low-carbon argument glosses over the industry's associated ecological and social costs. I draw on my recently published AWARE article on the political ecology of large dams in the Mekong Region, where the 'sustainable hydropower' discourse has increasingly enveloped project planning, construction and operation since the intense debate over construction of the Nam Theun 2 (NT2) project in Laos.

In response to the multistakeholder World Commission on Dams report (WCD, 2000), projects like NT2 were instrumental in offering a promise of 'better dams'. New tools such as the IHA's Hydropower Sustainability Assessment Protocol, the "San José Declaration on Sustainable Hydropower" (2021), and other efforts have sought to re-legitimize the industry, including as a climate change solution. In the Mekong Region, 'sustainable hydropower' has been institutionalized in the intergovernmental Mekong River Commission. However, few if any large dams have come close to attaining what has been promised (Williams, 2020). Flagship projects such as NT2 continue to remain contested for their social and environmental outcomes, while tragic disasters such as the Xe Pian Xe Namnoi dam collapse in 2018, and controversial mainstream dam projects such as the Xayaburi dam completed in 2019, all demonstrate that the idealised discourse of an era of 'sustainable hydropower' presented at COP26 is far from a reality.

Much of the emphasis of sustainable hydropower has been on technological fixes, such as fish passages, friendly turbines, and sediment flushing. Even when these technologies have been highlighted as examples of 'sustainable hydropower', as has been the case for the Xayaburi Dam, a lack of performance data in the public domain raises distrust on their effectiveness. In the Mekong Region, the World Bank-sponsored fish pass structure at the Pak Mun dam in Thailand is a long-standing reminder of technical fixes gone wrong. Sustainable hydropower tools have also emphasised public participation and impact assessment that, while an improvement on past practices, have been instrumentalised to attain project approval, and often take place in a context of limited civil, political and media freedoms, and project developer and state accountability.

The assertion that 'sustainable hydropower' is significantly more climate friendly than fossil fuel fired electricity generation has been questioned in recent research in the Mekong Region (Räsänen et al, 2018), and for other tropical rivers, which suggests these claims cannot be assumed without project-specific studies. If greenhouse gas emissions are a serious concern for electricity planners, then the preference for large hydropower seems to reflect a policy and planning bias, given that other non-hydro renewable technologies such as solar are now economically viable at scale, and there is also significant further potential for energy efficiency and demand side management.

Behind the sustainable hydropower discourse is the shifting political economy of large dams, that are now more likely to be built, financed and operated for profit by the private sector or as a public-private-partnership with the state, rather than by the state alone. A consequence is that the notion of large dams as a public good becomes conflated with, or supplanted by, the profit imperative. In the Mekong region, the commitment to 'sustainable hydropower' of regional construction companies, project developers, and financiers, who are not IHA members, is limited. Project operation is shaped primarily by electricity sales to distant locations, while impacts on river hydrology, ecosystems and common pool resources increase community vulnerability, further exacerbated by the impacts of climate change (Baird and Green, 2020; Käkönen and Thuon, 2019).

The 2000s came with some hope that more balanced decision-making could become a reality, including in the Mekong region and the wider global south. However, the practices of 'sustainable hydropower' that subsequently emerged at best have only nudged projects to be better than they otherwise would have been. Almost by definition, sustainable hydropower's purpose is to further the development of large dams, which in the process simplifies rivers to this end rather than taking a more holistic view of their multiple values (and ontologies). The discourse appears to serve the private interests that dominate the hydropower industry, and state concerns for prioritizing economic growth.

Sustainable hydropower is an idea whose time has come and gone, given the failure of the industry and state to substantially demonstrate sustainability in any shape or form. In the context of climate change, healthy rivers are a foundation of resilience, as well as social and ecological justice. At a minimum, more holistic approaches to water-food-energy-climate are needed, but presently these approaches are generally buried under a 'nexused' jargon that entrenches managerialism and a technical approach to energy production (Allouche et al, 2019). In some countries, mainly in the North, dam decommissioning programs are underway, or even rewilding rivers, acknowledging how rationalities justifying past dams have shifted and river ecosystems revalued. It is also important to continue to emphasize the importance of local commons, commoning and resource governance, nested in higher scales of commons (Hirsch, 2020).

More profoundly, in a growing number of countries globally, there is also a movement for the 'Rights of Rivers' as a means to re-think and re-legislate human-river relations. These approaches hold greater promise, and public resources for climate change solutions should be redirected towards then. Yet, while they offer a vision for the long term, can they work quick enough to address the impacts of the rapid impounding of the Mekong River basin now underway?

References

Agudo, P. A., Boyd, D., Fakhri, M., and Jimenez-Damary, C. 2021. Joint statement on the human rights of people affected by dams and other water infrastructure. Retrieved from https://www.ohchr.org/en/statements/2021/11/joint-statement-human-rights-people-affected-dams-and-other-water-infrastructure

Allouche, J., Middleton, C. and Gyawali, D. 2019. The Water-Food-Energy Nexus: Power, Politics and Justice London and New York, Routledge-Earthscan.

Baird, I. G. and Green, W. N. 2020. The Clean Development Mechanism and large dam development: contradictions associated with climate financing in Cambodia. Climatic Change. 161(2): 365-383.

Declaration. 2021. Climate mitigation efforts must reject so-called "sustainable hydropower" as a solution to combat climate change. Retrieved from https://www.internationalrivers.org/wp-content/uploads/sites/86/2021/11/Rivers-For-Climate-Declaration.pdf

Hirsch, P. 2020. Scaling the environmental commons: Broadening our frame of reference for transboundary governance in Southeast Asia. Asia Pacific Viewpoint 61(2): 190-202.

International Hydropower Association (IHA). 2021. IHA to COP26: Sustainable hydropower is essential for net zero emissions. Retrieved from https://www.hydropower.org/news/press-release-iha-to-cop26-sustainable-hydropower-is-essential-for-net-zero-emissions

Käkönen, M. and Thuon, T. 2019. Overlapping zones of exclusion: Carbon markets, corporate hydropower enclaves and timber extraction in Cambodia. The Journal of Peasant Studies 46(6): 1192-1218.

Moran, E. F., Lopez, M.C., Moore, N., Müller, N. and Hyndman, D.W. 2018. Sustainable hydropower in the 21st century. Proceedings of the National Academy of Sciences 115(47): 11891-11898.

Räsänen, T. A., Varis, O., Scherer, L., and Kummu, M. 2018. Greenhouse gas emissions of hydropower in the Mekong River Basin Environmental Research Letters. 13(3), 034030. doi:10.1088/1748-9326/aaa817

Williams, J. M. 2020. The hydropower myth. Environmental Science and Pollution Research 27(12): 12882-12888.

Photo: Xayaburi dam on the Mekong River; credit: Carl Middleton