The Water–Security Nexus

Water underpins virtually every dimension of modern economic activity and human survival. Agriculture, which accounts for approximately 70 per cent of global freshwater withdrawals, depends on it for crop production at a scale that makes large-population food systems structurally impossible without reliable access. Energy production, whether thermal, nuclear or hydroelectric, requires water for cooling, steam generation or direct power conversion. Industrial manufacturing, from semiconductor fabrication to steel production, consumes water in quantities that define the geographic viability of entire industrial sectors. Urban populations depend on complex water supply systems whose failure, even for short periods, produces immediate public health crises and cascading economic effects. And yet, in the strategic literature on conflict and national security, water has historically occupied a peripheral position, treated as a background condition rather than a decisive variable. That is changing, rapidly and structurally, driven by the intersection of climate stress, population growth and the demonstrated willingness of belligerents to target water infrastructure as a deliberate instrument of military and political coercion.

The numbers defining the current state of global water stress are significant enough to reframe how the resource is understood in strategic terms. Approximately 4 billion people, more than half the world's population, experience severe water scarcity for at least one month per year. Around 2 billion people live in countries experiencing high water stress. The World Resources Institute classifies 25 countries, home to a quarter of the global population, as facing extremely high baseline water stress, withdrawing more than 80 per cent of their available renewable freshwater supply annually. These countries include major geopolitical actors across the Middle East, North Africa, Central Asia and South Asia whose political stability, agricultural capacity and economic development trajectories are all directly conditioned by their water situation.

The demand side of this equation is not improving. Global water demand is projected by the OECD to increase by approximately 55 per cent between 2000 and 2050, driven primarily by manufacturing growth (400 per cent increase projected), electricity generation (140 per cent) and domestic use (130 per cent). Meanwhile, supply is becoming less predictable as climate change alters precipitation patterns, accelerates glacial retreat, reduces snowpack accumulation in mountain systems and increases evaporation rates across already-stressed basins. The Himalayan glaciers that feed the major river systems of South and Central Asia, supplying freshwater to approximately 2 billion people across ten countries, are retreating at accelerating rates. The Nile, the Jordan, the Tigris-Euphrates, the Indus and the Yellow River systems are all under simultaneous stress from increasing demand, decreasing supply and upstream infrastructure development that reconfigures how available water is distributed between the states that share these basins.

The world's major river systems do not follow political borders. Of the world's 263 international river basins, spanning 145 countries and covering approximately 45 per cent of the earth's land surface, many lack functional multilateral governance frameworks capable of managing the tensions created by upstream development and downstream dependency. The political economy of transboundary water management is structurally asymmetric: upstream states possess the ability to reduce downstream flows through dam construction, diversion and consumptive use, while downstream states typically have limited legal and practical mechanisms to prevent or compensate for that reduction. This asymmetry creates a persistent structural incentive for upstream states to develop water infrastructure unilaterally, and for downstream states to treat that infrastructure as a strategic threat.

The cases where this structural tension has produced, or is actively producing, serious geopolitical friction are numerous and escalating. Egypt has explicitly and repeatedly stated that the filling and operation of Ethiopia's Grand Ethiopian Renaissance Dam represents a threat to its national security, and senior Egyptian officials have not ruled out military options in response. President El-Sisi has stated publicly that water is an existential matter for Egypt and that no one should test Cairo's will when its vital interests are threatened. The legal framework for resolving the dispute, including the 1959 Nile Waters Agreement that allocated river flows between Egypt and Sudan without Ethiopia's participation, provides no adequate basis for multilateral resolution. The GERD standoff is, in structural terms, the most consequential transboundary water dispute currently active, involving a country of 105 million people entirely dependent on a single river for its freshwater and agricultural capacity.

The deliberate targeting of water infrastructure in armed conflict has a long history, but its frequency and strategic intentionality have increased markedly in contemporary conflicts. The destruction of water infrastructure in warfare constitutes a breach of international humanitarian law under the 1977 Additional Protocols to the Geneva Conventions, which prohibit attacks on objects indispensable to civilian survival, including drinking water installations and irrigation works. In practice, this prohibition has proved ineffective in constraining attacks on water systems across multiple recent conflicts, because the dual-use character of water infrastructure, serving both military and civilian populations simultaneously, provides legal ambiguity that belligerents exploit.

Syria's civil war produced some of the most extensively documented attacks on water infrastructure in modern conflict history. The water supply systems of Damascus, Aleppo, Deir ez-Zor and multiple other urban centres were repeatedly targeted by various parties to the conflict, using both direct military strikes and deliberate contamination of water sources. UNICEF documented 67 attacks on water infrastructure in Syria between 2013 and 2017 alone. The Islamic State group demonstrated particular strategic sophistication in its use of water as a military tool, seizing control of the Mosul Dam in Iraq in August 2014 and using the threat of dam destruction as leverage in negotiations. The group also cut water supplies to government-controlled areas as a siege tactic and diverted irrigation water to flood military positions. These were not incidental effects of combat. They were deliberate tactical decisions reflecting an understanding that control over water infrastructure confers direct military and political leverage.

Water and energy systems are deeply and structurally interdependent in ways that amplify the consequences of disruption to either. Energy production requires water at multiple points in the production chain: thermal power stations use water for cooling at rates that make them highly water-intensive per unit of electricity generated; hydroelectric systems depend entirely on water availability; nuclear power stations require reliable cooling water supply; and the extraction and processing of fossil fuels consumes water at significant rates. At the same time, water systems require energy to function. Pumping water from source to consumer, treating it to potable standard and distributing it through pressurised networks all require continuous electricity input. In situations where energy supply is disrupted, water supply degrades in parallel. In situations where water supply is disrupted, energy production capacity may be constrained simultaneously.

Ukraine's conflict illustrates this interdependence acutely. Russia's attacks on Ukrainian electricity generation infrastructure directly degraded the country's ability to pump and treat water for civilian and agricultural use. Power outages of four to eight hours per day during peak winter demand periods reduced water pressure in urban distribution systems, limited the capacity of water treatment plants to maintain safe treatment levels and compromised irrigation pump operations in agricultural areas. The Kakhovka dam destruction eliminated both the hydroelectric generation capacity of the dam and the irrigation water supply for approximately 500,000 hectares of agricultural land simultaneously, demonstrating that single acts of infrastructure destruction can cascade across multiple interdependent systems in ways whose full consequences take years to fully measure.

Cities are the most exposed human systems to water stress and water infrastructure disruption, because their dependence on complex, centralised supply infrastructure creates a single-point vulnerability that cannot easily be mitigated by individual adaptation. A rural household facing water scarcity can draw from a well, collect rainfall or walk to an alternative source, at significant cost to time and productivity but without immediately catastrophic consequences. An urban population of several million people dependent on a centralised treatment and distribution system has no comparable alternative. When that system fails, the consequences are immediate, universal and cascade rapidly from public health into economic activity and social order.

The economic consequences of urban water stress extend well beyond the direct costs of disrupted supply. Industries dependent on reliable water supply, including food processing, textiles, pharmaceuticals and electronics manufacturing, face production constraints that reduce output and increase costs. Commercial real estate in water-stressed cities faces declining values as the investment risk premium associated with water vulnerability is progressively priced into the market. Skilled workers increasingly factor water security into location decisions, creating a talent drain from highly water-stressed cities toward more water-secure alternatives. Governments facing fiscal stress must simultaneously maintain subsidies on water prices to prevent social unrest and fund the capital investment required to upgrade ageing infrastructure, creating a fiscal trap that perpetuates the underlying vulnerability. Nairobi, Cairo, Karachi, Lahore and multiple Chinese cities are all navigating versions of this trap simultaneously, with varying degrees of institutional capacity and political will to address it.

The trajectory of global water stress points toward a future in which water scarcity, infrastructure vulnerability and transboundary competition will be significantly more acute than they are today, across a wider range of geographies and involving a larger number of states with fewer institutional mechanisms for peaceful resolution. The combination of climate change, population growth and upstream dam development is not a set of independent variables that will reach equilibrium through market mechanisms or diplomatic goodwill. It is a set of compounding pressures whose combined effect over the next two to three decades will impose genuine existential constraints on the strategic choices available to several states currently operating at the margins of sustainable water access.

For states in the Global South, this trajectory creates a compound challenge. Many of the countries most exposed to water stress are simultaneously dealing with the other pressures documented throughout this edition: rising military expenditure consuming fiscal space that might otherwise fund water infrastructure investment, food insecurity driven partly by water-constrained agricultural production, energy systems dependent on hydroelectric generation threatened by reduced river flows, and governance structures under political stress that reduces the institutional capacity to manage long-term infrastructure challenges. Water does not appear on most conflict risk assessments as a primary driver. It appears as a background condition or a contributing factor. That framing is increasingly inadequate for the scale of the challenge that is approaching.