Regardless of where we live, we all depend in some way on mountains and glaciers. But these essential natural water towers are facing imminent peril. This report demonstrates the urgent need for action and that the most effective solutions require a multilateral approach.
Audrey AzoulayUNESCO Director-General
Water flows downhill, but food insecurity rises uphill. The earth's mountains provide 60% of our freshwater, but the communities that safeguard these vital resources are among the most food insecure. We must invest in their resilience to protect glaciers, rivers - and a shared future for all of us.
Alvaro LarioPresident of the International Fund for Agricultural Development (IFAD) and Chair of UN-Water
Two billion people depend on mountain waters
According to the UN World Water Development Report 2025, mountains provide up to 60% of the world's annual freshwater flows. More than one billion people live in mountainous regions, and over two billion directly rely on water originating from mountains for their drinking water, sanitation, and livelihoods.
Mountain regions are vital to sectors such as pastoralism, forestry, tourism and energy production. In the Andean countries 85% of hydropower is generated from mountain areas. Mountains also provide high-value products such as medicinal plants, timber and other forest products, unique mountain livestock and speciality agriculture products - all of which are water-dependent.
However, the Report indicates that glaciers across the world are melting at unprecedented rates, and that mountain waters are often the first to be exposed - and the most vulnerable - to the severe consequences of climate and biodiversity disruptions.
Today the situation is critical: up to half of rural mountain dwellers in developing countries suffer from food insecurity, with women and children being most at risk. More broadly, the Report reveals that receding glaciers and dwindling snowfall in mountains will impact two-thirds of all irrigated agriculture in the world and will have wide-reaching implications for the vast majority of the population.
Glacier retreat is only the visible part of the threat
While images of receding glaciers capture the public's attention, they are just one example of the rapid changes happening in mountain areas. In many regions, freshwater flows depend more on seasonal snowpack melt than on glaciers.
Due to climate disruption, rapid changes in the amount, frequency and regularity of snowfall are severely disrupting the water supply, creating unstable environments for biodiversity, and unpredictable conditions for human livelihoods. In Japan, for example, the iconic snowcap on Mount Fuji, a UNESCO World Heritage site, has recently started appearing nearly one month later than usual.
These changes in precipitation are also increasing the risk of natural disasters such as droughts and glacial lake outburst floods. The Colorado River in North America, which serves about 40 million people, gets most of its water from snowfall in the Rocky Mountains. The river basin has been in drought since 2000. The situation may become exacerbated by warmer temperatures, which are causing more precipitation to fall as rain, which runs off more quickly than mountain snow.
Climate disruption is also being felt strongly in mountain regions with no recorded glaciers or snowmelt, where water flows originate instead from rainfall. In tropical regions, such as Madagascar, changes in mountain waters are impacting the irrigation of cacao, rice and fruit production - some of the island nation's most important agricultural exports.
Impactful solutions are multilateral
Despite their essential role, the Report highlights that mountain regions have been largely absent from global agendas. National policies for water, agriculture, industry and energy tend to favour more populous river basin areas, while mountains generally receive much less attention - or are often only considered as sources for downstream users.
This year marks the launch of the first-ever World Day for Glaciers on 21 March, emphasizing the need for immediate and coordinated international efforts, aligned with World Water Day on 22 March. UNESCO is co-leading the Day with WMO as well as the 2025 International Year of Glaciers' Preservation, a global initiative to mobilize resources and commitments for glacier conservation, and the Decade of Action for Cryospheric Sciences (2025-2034) to advance scientific understanding and policy solutions.
These major events must give rise to a new impetus for international cooperation for the protection of glaciers and mountain waters. Many mountain ranges and their ecosystem services are transboundary in nature: treaties or agreements can enhance cooperation through data and information sharing, help to fill gaps in human and institutional technical capacity, and promote and foster dialogue and diplomacy.
Drawing inspiration from existing cooperation projects
In response to the growing crisis outlined in the Report, there is an urgent need adapt to this new reality and strengthen water security worldwide through scientific research, policy coordination, and concrete action on the ground.
In Central Asia, UNESCO has recently mobilized USD 12 million to reduce disaster risks and enhance scientific cooperation, including a new regional glacier monitoring system deployed this year across the region's transboundary glacial massifs. UNESCO is also establishing an Early Flood Warning System in Kazakhstan, Kyrgyzstan, and Uzbekistan which will help protect over 100,000 people at risk from glacial lake outburst floods.
In Africa, UNESCO is leading the "Unlocking the Kilimanjaro Water Tower" project, funded with USD 8 million from the the Global Environment Facility. It will benefit more than 2 million people in Tanzania and Kenya who depend directly on the waters of Africa's highest peak. Experts from both countries will map the region's aquifer systems and give an additional 100,000 people direct access to drinking water. They will improve groundwater storage and supply during the dry season. This initiative will also restore 400 km² of degraded cloud forests and put more than 17,000 km² of protected areas under reinforced management.
