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The weighty benefits of dams
Chair in International Law, School of Law, University of Aberdeen
The more than 260 international river basins are very important source of freshwater to billions of people in our planet and they provide a wide-range of benefits to society, countries and to the natural environment.
One of the usual ways of making use of river freshwater is constructing dams and creating reservoirs for various purposes. Small scale dams are, in fact, largely seen positively for socio-economic development and conservation of natural resources.
They are constructed with proper study, environmental impact assessment
Mega dams, by contrast, are proved to be very controversial among scholars and activists of environmental protection. The International Commission of Dams considers mega dams as economically, environmentally highly beneficial to society provided that they are constructed with proper study, environmental impact assessment, and carefully filled, operated and managed.
This is why international and/or national water law and other widely accepted standards, such as the principle of equitable utilisation, the duty to prevent significant harm to riparians and the obligation to protect ecosystems, ought to be followed, to ensure that the construction, filling and operation of mega dams promote inclusive and environmentally sustainable development.
Mega dams certainly come with their financial and safety risks and changes to hydrological flow of water. They could also affect the livelihood of humans, plants and wild animals. However, subject to the safety and legal requirements, the benefit of mega dams outweigh their disadvantages:
Comparatively less, preventable and manageable risks
First, mega dams bring tremendous socio-economic growth for countries and their populations. They enable them to secure: a) food through large-scale irrigated farming or expansion and modernisation of fisheries, b) renewable energy through hydropower generation, c) significant income from tourism and recreation, d) access to clean water to cities and e) river navigation. The mega dams in the Americas, Asia, Europe and Africa are clear evidences of such benefits, although most of these dams might, or might not, satisfy the internationally recognised standards of construction, operation and environmental protection.
Secondly, any mega project comes with its own risks. When compared with the other alternatives of energy projects, in particular nuclear power projects, however, mega dams not only provide renewable energy but also come with comparatively less, preventable and manageable risks for generations to come.
Thirdly, dams could positively contribute to a better natural and man-made environment through regulating flooding, water flow and slit, thereby help encounter the potential effects of climate change.
This assessment proves two important findings: that the benefits of dams, compared to their negative impacts, are weighty, as confirmed in the role of mega dams in the economic advancement of developed countries, and that each mega dam must be judged on its merits, either to acclaim or denounce it as environmentally decent or not so decent.
Large dams do not benefit the environment
Director of programs, International Rivers
Large dams are catapulting a range of species toward extinction. They are flooding critical carbon sinks and depriving still others of their sustenance. And dams are the greatest single source of manmade emissions of methane: the most potent of greenhouse gases. Needless to say, it’s hard to argue dams benefit the environment. That is, unless, you stand to profit from the greenwash.
Dams are the greatest single source of manmade emissions of methane: the most potent of greenhouse gases
On May 14-16, the World Hydropower Congress will convene in Paris with the supposed commitment to deliver on the Paris Climate Agreement and Sustainable Development Goals. It’s a convenient posture given the money now available to mitigate climate change through mechanisms like the Green Climate Fund (GCF). In addition to drawing money (some $130 million in the case of but one project in Tajikistan alone) from newer, greener technologies, large hydro is, as close to 300 NGOs have noted in a letter to the GCF: inefficient, ineffective, and disrupts the function of rivers as regulators of the carbon cycle.
So why, despite the preponderance of evidence that large hydro is bad for the environment is it maintaining its green luster? For this, you need look no further than the co-host of the upcoming World Hydropower Congress: the United Nations Educational, Scientific and Cultural Organization (UNESCO). UNESCO is at once the international body responsible for selecting World Heritage Sites for legal protection, while at the same time legitimizing an industry that threatens close to 20 of these sites.
A further aspect of the greenwash is the argument that hydropower is the lesser of two evils. It is less caustic to the environment than conventional power sources so it is thus beneficial to the environment. Needless to say, there are fallacies in this premise. First, studies are finding that in tropical environments and high-sediment areas, dams can release more greenhouse gases than coal-fired power plants. Second, even if large dams were less caustic, their carbon footprint is by no means beneficial nor comparable to alternatives like wind and solar.
Even if large dams were less caustic, their carbon footprint is by no means beneficial nor comparable to alternatives
It’s time for those institutions giving credence to the myth of “dams as eco-savior” to shift course, before this supposed “solution” to climate change accelerates us even faster to toward the Intergovernmental Panel on Climate Change’s point of no return.