Water stress: the new politics of water

Water scarcity is already a global problem. Around four billion people experience severe water scarcity for at least one month a year. Twenty-five countries, home to a quarter of the world’s population, face extreme water stress on a permanent basis (1). Yet the problem cannot be captured by annual water availability alone. Even regions with sufficient water resources on an annual average can experience severe seasonal water stress when supply and demand fall out of sync.

This shift is particularly visible in Switzerland. Snow and glaciers act as natural reservoirs, storing precipitation in winter and releasing it as meltwater in summer. But this storage function is weakening. Since 2015, Swiss glaciers have lost around a quarter of their volume (2). According to the Swiss Glacier Monitoring Network (GLAMOS), so-called “peak water” has already been reached. As glaciers continue to shrink, meltwater runoff is therefore expected to decline over the long term (3).

A further factor is the growing seasonal shift in water availability. Longer dry spells are increasingly accompanied by short, intense rainfall events, which contribute less to the steady replenishment of soils, groundwater and rivers. This is particularly relevant in summer. Irrigation demand in agriculture rises precisely when river flows are falling. This intensifies competition among agriculture, drinking-water supply, hydropower and ecosystems for the same resource at the same time. The Swiss Federal Office for the Environment (BAFU) sums up the development accordingly: Switzerland remains a water tower in terms of overall volume, but climate change is altering “when and where water is available” (4).

Water is becoming a strategic resource

Water scarcity has ecological consequences and direct effects on agriculture, but its implications go further. As scarcity increases, so too does the question of who has access to available water resources, when, and under what conditions. This gives water an increasingly political and strategic dimension. Conflicts over use among agriculture, energy production, households and industry are likely to become more frequent. Nor do they stop at national borders.

Such conflicts are already becoming visible even in water-rich Switzerland. In July 2026, authorities in the Italian region of Piedmont asked the Swiss canton of Ticino to release additional water from its reservoirs to support agriculture suffering from drought. Ticino refused, citing its own limited reserves and their importance for electricity production in winter. A similar situation had already occurred during the hot summer of 2022 (5).

Such allocation questions become particularly sensitive when several states share the same reservoirs or river systems. This is already evident at Lake Maggiore. The lake’s water is important for agriculture in Italy’s Po Valley, while reserves are also becoming scarcer in Ticino. There is still no comprehensive framework governing such scarcity situations. The Swiss federal government, the Canton of Ticino and the Italian authorities are currently laying the groundwork for such an agreement.

At Lake Geneva, cross-border cooperation is already more firmly institutionalised. After more than a decade of negotiations, Switzerland and France signed an agreement in September 2025 regulating the waters of Lake Geneva. On the French side, the issue was promoted at the highest political level by François Hollande and Emmanuel Macron (5). The fact that the management of a water reservoir long regarded as abundant has become the subject of interstate negotiations shows that water management is no longer merely a technical issue. It has become a political question of who gets a say, how shared resources are managed and how competing national interests are reconciled as supplies become less reliable.

These examples offer a glimpse of the new politics of water. In the future, competing claims on the same resource are likely to become more common, especially as water becomes scarcer and its availability more seasonal and less predictable. The political importance of storage and control mechanisms will grow accordingly, increasing water’s economic and strategic value. In regions facing structural water scarcity, access to water may increasingly be understood not only as an environmental or economic issue, but also as a matter of critical infrastructure and, ultimately, national security.

Water conflicts are rising sharply

What in Switzerland still largely appears as a regulatory and economic conflict of interest is already far more acute in other parts of the world. The spectrum extends to interstate tensions and violent conflict. In recent years, the number of documented water-related conflicts has risen sharply. For 2024, the Pacific Institute records 420 water conflict events worldwide. That is 18 per cent more than the previous year and almost twenty times as many as in 2010. Water is not necessarily the sole cause of these conflicts. It can act as a trigger or a means of pressure, become a strategic target, or itself be affected by existing conflicts.

While most water conflicts take place locally within states, for example in the context of civil wars or between different social groups competing over access to water, interstate conflicts are also increasing. Since 2021 in particular, the rise in both types of conflict has accelerated markedly (6).

How water can be drawn into geopolitically charged conflicts and used as leverage is illustrated by the recent escalation between India and Pakistan. Following the Pahalgam terrorist attack in April 2025, India suspended the 1960 Indus Waters Treaty. In parallel, the broader crisis escalated into direct military clashes. Pakistan declared that any attempt to stop or divert water to which it is entitled would be considered an “Act of War” (7, 8). India continues to keep the treaty suspended. The case shows how even arrangements that have endured for decades can come under growing geopolitical pressure.

The dispute over the Grand Ethiopian Renaissance Dam (GERD) on the Blue Nile is also highly politicised. Ethiopia regards the dam as a key project for electricity supply and economic development, while Egypt and Sudan see it as a threat to their water supply (9).

Both cases show how control over dams, river flows and hydrological information can become politically charged and part of strategic confrontation. Similar configurations can be found on the Euphrates, Tigris and Mekong. A particularly clear example is China’s cascade of large dams on the upper Mekong, which gives Beijing significant influence over seasonal flows. The downstream states of Laos, Thailand, Cambodia and Vietnam depend heavily on reliable river flows (10, 11).

The geoeconomic dimension of water stress

The strategic importance of water is not limited to allocation disputes and conflicts. Rising water stress is also disrupting critical infrastructure and trade routes.

At the Panama Canal, drought in 2023 and 2024 temporarily halved the number of possible daily ship transits from around 36 to 18. The result was delays, capacity constraints and higher transport costs. The canal is under renewed pressure in 2026. With El Niño developing and water levels expected to fall, the canal authority has again introduced draft restrictions (12, 13).

Low water levels on the Rhine, Mississippi and Danube similarly reduce cargo capacity, raise freight costs and disrupt industrial supply chains. ING warns that the current restrictions on Rhine shipping could reduce Germany’s gross domestic product (GDP) growth by up to 0.3 percentage points in 2026 (14, 15).

At the same time, the long-term decline in the level of the Caspian Sea is putting the increasingly strategic Middle Corridor between China and Europe under pressure (16).

Water scarcity is also becoming a risk to energy security. Low water levels or high water temperatures can force nuclear and coal-fired power plants to reduce output or shut down because of insufficient cooling water. Low reservoir levels also constrain hydropower generation. The International Energy Agency (IEA) warns that water scarcity is already affecting energy production and security of supply and, as water stress intensifies, could also constrain the technical and economic viability of future energy projects (17, 18).

Beyond its impact on energy security, water availability is increasingly shaping where agriculture, industry, power generation and digital infrastructure can operate economically. Regions with reliable water resources may gain in attractiveness, while rising water stress increases costs, supply risks and economic vulnerability elsewhere.

These shifts also give water a growing geoeconomic dimension. Where states control rivers, reservoirs or other water infrastructure on which others rely, access to water can become a source of leverage, much like control over energy resources or critical transport routes. Over time, water could therefore reshape the geography of economic activity and alter the balance of power between regions and states.