Mountains and Glaciers: Water towers
Mountain waters are essential to humans and ecosystems
The 2025 edition of the United Nations World Water Development Report highlights the importance of mountain waters, including alpine glaciers, which are vital for meeting basic human needs such as water supply and sanitation. They are also essential to ensuring food and energy security to billions of people living in and around mountain regions and areas downstream. They also support economic growth through various water-reliant industries. As the ‘water towers’ of the world, mountains are an essential source of fresh water. They store water in the form of ice and snow during cold seasons, releasing it during warmer seasons as a major source of fresh water for users downstream. Mountains play a unique and critical role in the global water cycle, and they affect atmospheric circulation, which drives weather and precipitation patterns.
International Year of Glaciers' Preservation
Climate change is accelerating glacier melt, decreasing snow cover, increasing permafrost thaw, and causing more extreme rainfall events and natural hazards leading to more variable, erratic and uncertain water flows. This highlights the urgency of improving mountain water governance through integrated river basin management, finance, and knowledge- and capacity-building, to meet the world’s ever-growing demand for water.
In the context of the , the UN World Water Development Report 2025 draws attention to the importance of mountain waters to the downstream societies that depend upon them, with a focus on the impacts of the rapidly changing mountain cryosphere, the Earth’s surface covered by water in its solid forms (glaciers, ice caps, snow, permanently frozen ground).
Facts and figures
Key messages
Contributing partners
UN-Water members that contributed to the UN World Water Development Report 2025
