In the Valle dei Laghi region of northern Italy, a delicate balance that has long sustained local agriculture and powered the entire Trentino province is faltering. Water flowing from the mountains feeds the Santa Massenza hydroelectric plant and irrigates valuable vineyards, but accelerating climate change is disrupting this equilibrium. Consecutive dry years and extreme weather events are shrinking the water resources that are vital to both energy production and one of the nation’s most important agricultural sectors.
The core of the problem lies in fundamental shifts to the hydrological cycle in the Alps. Warmer temperatures mean less winter precipitation falls as snow, reducing the mountain snowpack that traditionally acts as a natural reservoir, releasing water slowly during spring and summer melt. This has led to critically low snow accumulation in recent winters, contributing to low-flow conditions in major rivers like the Po and Adige. As a result, mountain regions are seeing increased water runoff in the fall and winter, when demand is lower, and significantly decreased discharges during the critical spring and summer growing seasons. Projections indicate that summer water flows in some southern European regions could eventually be reduced by as much as 80%.
Hydropower Production in Decline
Italy relies on its nearly 5,000 hydroelectric plants for about 15% of its energy, making the changes in mountain water flow a national concern. In Trentino, the Santa Massenza plant’s operation is directly threatened by the reduced availability of water from the surrounding mountains. The impact is not theoretical; between 2019 and 2023, a series of dry years caused a 30% reduction in the country’s hydropower output. This sharp decline significantly decreased the share of renewable energy in Italy’s total production, highlighting the vulnerability of the nation’s power grid to climate-driven hydrological changes. Research from as early as 2009 projected that shifting runoff regimes would lead to a decrease in energy generation from Alpine hydropower plants.
A Stressed Agricultural Sector
After hydropower, agriculture is Trentino’s largest consumer of fresh water, with wine grapes being the region’s most significant agricultural product by both volume and value. The recent dry years have placed immense stress on vineyards, threatening the industry. In 2023, a combination of a hot summer, hailstorms, and fungal diseases fueled by extreme weather led to a 13% drop in Italy’s grape production compared to the previous year. This crisis caused Italy to lose its position as the world’s largest wine producer that year.
A Grower’s Perspective
Local winegrowers are witnessing the changes firsthand. Stefano Pisoni, whose family has grown wine in Valle dei Laghi since 1852, notes the erratic nature of the weather. “The feeling is as if the weather no longer has an identity, because now you are experiencing the weather with extremes too hot, too cold, periods too dry, periods too wet, as if the weather itself doesn’t know what it’s supposed to do,” Pisoni said. He explained that these weather extremes create stress in the plants, making them more susceptible to diseases that have become much stronger in recent years.
Intensifying Drought Conditions
The challenges seen in the Italian mountains are symptomatic of a broader trend across southern Europe. Climate change is expected to bring further reductions in water quantity, quality, and availability, with droughts increasing in both frequency and intensity, particularly in the summer. Scientists have concluded that global warming will have a much more significant impact on droughts than on floods in the Alps. While the magnitude of flood events is not expected to change significantly, droughts are projected to become more intense and last longer. This trend extends below the surface, as changing precipitation patterns and higher temperatures are also expected to reduce groundwater recharge, causing fresh groundwater resources to shrink, especially in coastal areas.
Searching for Resilient Solutions
In response to the crisis, water managers and farmers in Trentino are pursuing innovative solutions. The region has a history of advanced water management, and for more than two decades, farmers have used drip irrigation to conserve water drawn from the hydroelectric system. However, Bruno Lutterotti, head of the Alto Garda Irrigation Consortium, stated that the more drastic effects of climate change mean this system is now reaching a critical moment.
New Strategies for Water Management
The recent crisis prompted Lutterotti’s consortium to initiate a project to create a better model for water management. The EU research project IMPETUS is supporting this initiative with a tool designed to strengthen the region’s resilience. Potential measures being explored include using new technology to find and repair leaks in water pipes, protecting and utilizing natural areas like wetlands for water storage, and engaging the community to ensure the problems are understood. With climate change intensifying, new solutions are essential for the Valle del Laghi to adapt to a future where water is an increasingly precious resource.
