Colloquium: Prof. Andrea Castelletti

Ongoing changes in global climate are altering the hydrologic regime, expanding historically observed variability as well as increasing the frequency and intensity of extreme events. Evidence of this emerging behavior has been observed worldwide, including traditionally flood sensitive regions, such as the Italian Alps, where intensive droughts have repeatedly challenged agricultural and hydropower production in the last decade. “Hard-path" solutions, such as investing in new infrastructure to expand water supply capacity, require large investments, and are becoming economically, socially and environmentally unsustainable. “Soft-path” measures, based on decentralized facilities, smart technologies, coordination mechanisms, more informed and effective decision-making, represent an interesting alternative to the hard-path approach.

In the last two decades, we have been exploring the concept of soft-path solutions from multiple angles, and developing tools based on high performance computing and machine learning to facilitate its implementation in real world contexts. We have been focusing on the role of more- and better-informed decisions as well as coordination mechanism design, including financial risk hedging tools, to improve existing water management practices. In the Northern Italy lake district, extensive model-based analyses show that a soft-path approach can substantially mitigate the impact of changing climate, and help contrasting increasingly frequent and impacting droughts with little financial investment but a substantial shift in the existing water governance system.