Mathematics can help plan increasingly sustainable dams, reducing their environmental impact without compromising energy generation and food production: evidenced by the winning research in the sixth edition of the Aspen Institute Italia Prize for Cooperation and Scientific Research between Italy and the United States. States.
Awarded during a digital ceremony, the award was given to researchers Raphael JP Schmidt, Simone Bizzi, Andrea Castelletti and J. Mathias Kondolph, who conducted the study between Politecnico di Milano, UC Berkeley, Stanford University and University of Padua.
“We are very proud to receive this recognition – says Andrea Castellitti, Full Professor in Natural Resource Management at Politecnico di Milano – first and foremost because it not only assesses the scientific merit of our research, but also recognizes its social impact, and then because of its international dimension and strengthens the relationship that Our research group has been connecting for years with colleagues abroad, especially in the United States.”
The spark that motivates this collaboration has always been the researchers’ curiosity: in the case of the study awarded by the Aspen Institute, a method was sought to combine knowledge of the physical processes of rivers with the experience accumulated at Politecnico di Milano in the field of mathematical modeling applied to water resource management. This has led to the development of a mathematical model that allows the large-scale impact of dam construction to be assessed.
The hydroelectric development of large river basins is a central component of economic and social development in many countries: the world’s largest dams generate about one sixth of the electricity consumed and irrigate one seventh of agricultural fields. However, at the same time they significantly alter the natural order of river processes as they modify hydrology, impede sediment transport and fragment the ecosystem, sometimes irreparably damaging the ecological balance.
“The sustainability of dams depends on many aspects: We focused on sediment, assessing how the location of the dams affects the tons of sediment that reaches the delta,” Castelletti explains. The study was conducted on the Mekong River, where strong hydroelectric development is expected in the coming years.
The current situation generates 54% of the planned hydroelectricity, reducing sand toward the delta by 91% compared to the situation without dams. By adopting a strategic planning approach to determine where and how much to build dams, it was possible to produce 68% of the planned energy while reducing sand transport by only 21%.
Castelletti notes that “the significance of these findings opens up important spaces for discussion for the planning of 3,700 large dams awaiting construction in the world, especially in Southeast Asia, along the Amazon and African rivers.” “In the meantime, our research continues to add new elements that allow the mathematical model to assess, for example, the impact of dams in terms of greenhouse gas emissions.”