Brahma Chellaney, Special to The Globe and Mail

The U.S.-Israeli war on Iran crossed a dangerous threshold that few have yet fully grasped. It was not just one more Middle Eastern conflict defined by missiles, drones, bunker-busting bombs and cyberwarfare. It marked the normalization of something far more insidious: the deliberate targeting of water facilities.

Water itself became a weapon of war in a region already defined by extreme scarcity of the world’s most vital resource. 

This weaponization was not incidental: it was deliberate, reciprocal and escalating, with implications far beyond the Persian Gulf.

The Middle East is the most water-stressed region in the world, with over 80 per cent of its population living under conditions of extreme scarcity.

Within this region, the Persian Gulf stands out for its acute water scarcity, with per capita renewable freshwater availability falling well below the “absolute” scarcity threshold of 500 cubic meters per year in most countries. Contrast that with between 80,000 and 100,000 cubic meters per capita availability in Canada, which, along with Brazil and Russia, ranks among the richest in freshwater resources. 

The Gulf Arab countries and Iran’s coastal areas and islands rely heavily on desalination rather than renewable internal water resources, which are less than 100 cubic meters per capita in all the Gulf sheikhdoms other than Oman. 

In such an environment, water infrastructure is not just civilian; it is existential.

What the war revealed was a profound transformation in how such infrastructure is perceived. Desalination plants, water treatment systems and electrical grids that sustain them were no longer treated as protected civilian assets; they became targets.

Early in the conflict, damage to desalination facilities in Kuwait and the UAE was dismissed as collateral — an unfortunate byproduct of strikes on nearby military installations. That illusion did not last. Within days, the logic of retaliation took hold.

On March 7, a desalination plant on Iran’s Qeshm Island was struck, cutting off water to dozens of villages. The very next day, an Iranian drone targeted a desalination facility in Bahrain, disrupting supply to civilian areas.

A taboo had been broken. Water-for-water retaliation had entered the battlefield.

The anatomy of vulnerability

Nowhere is such escalation more dangerous than in the energy-rich Gulf Arab nations. These petro-states are, more precisely, “saltwater kingdoms,” surviving by converting seawater into potable water through desalination.

Yet this highly energy-intensive technological solution, long seen as a triumph of engineering over geography, revealed itself as a strategic weakness in wartime because of the plants’ vulnerability to attack.

In some Gulf states, up to 90 per cent of drinking water comes from desalination. These supplies are produced by a small number of massive, highly visible coastal facilities that are nearly impossible to fully defend. 

Most states maintain only three to seven days of potable water reserves, although some are now working to expand them. A successful strike on a major plant could leave millions without water in less than a week.

In other words, modern Gulf cities — from Dubaito Doha toRiyadh — are never more than a few days away from a total water blackout.

Iran, for its part, faces a different but equally severe water crisis. It is not dependent on desalination to the same degree, but population and economic growth and resource mismanagement have pushed it into virtual “water bankruptcy,” with consumption exceeding natural replenishment. Aquifers have been depleted, rivers diminished and ecosystems like Lake Urmia nearly disappeared.

Even before recent U.S. and Israeli airstrikes on critical infrastructure compounded these pressures, Iran’s president Masoud Pezeshkian had proposed relocating the capital to a wetter area, warning that Tehran’s deepening water crisis could render the city “uninhabitable.”

The infrastructure asymmetry between the Gulf states and Iran creates a volatile dynamic. The Gulf states are technologically resilient but physically exposed. Iran is structurally fragile but less vulnerable to single-point infrastructural collapse.

War turned these vulnerabilities into targets.

What distinguished this conflict was not simply that water infrastructure was hit, but that it was targeted as part of a deliberate strategy.

The logic is straightforward: modern societies depend on tightly integrated systems — electricity powers water infrastructure, and water sustains public health, industry, agriculture and social stability. Disrupt one node, and the entire system begins to unravel.

The U.S. understands this well. During the 1991 Gulf War, it systematically destroyed Iraq’s electrical grid, disabling water purification systems. The consequences were catastrophic: contaminated water supplies, collapsing hospitals, surging waterborne diseases and rising child mortality.

A subsequent study analyzing declassified U.S. Defense Intelligence Agency (DIA) documents concluded that the destruction of electricity and water-treatment infrastructure effectively functioned as a “biological weapon in slow motion.” One cited DIA document, “Iraq’s Water Treatment Vulnerabilities,” detailed how sanctions combined with electrical-grid destruction would produce “incidences, if not epidemics, of disease.”

In the Iran war, that logic — using electricity and water systems as instruments against civilian populations — was being reapplied.

Threats by U.S. President Donald Trump to destroy Iran’s electricity and desalination plants and broader energy infrastructure underscored how deeply that approach was embedded in thinking. Iran’s response was to mirror that logic in its own retaliatory approach.

Civilian lifelines were recast as instruments of coercion. The result was an emerging doctrine of “hydro-warfare,” one that threatened to intensify an already acute regional water crisis.

There was also an “invisible front” in this hydro-warfare: cyberattacks.

The war began with one of the largest cyberattacks in history, disrupting Iran’s digital infrastructure and crippling the automated systems that manage water distribution. A prolonged near-total internet blackout followed. In response, Iranian-linked cyber groups targeted industrial control systems associated with water and wastewater facilities across the region.

Such attacks aimed not to destroy infrastructure physically, but to manipulate its “digital brain” — to disrupt flow, degrade supply or trigger system-wide failures.

Unlike conventional strikes, cyber operations offer deniability and scalability. They blur the line between war and sabotage, making attribution difficult and escalation harder to control.

But their effects are no less real. A malfunctioning water system can be as devastating as a bombed one.

The collapse of legal restraints

International humanitarian law is unequivocal. The Geneva Conventions, reinforced by Additional Protocol I, explicitly prohibit attacks on objects indispensable to civilian survival — water facilities foremost among them.

Yet the Iran war suggests that these norms are rapidly eroding. Mr. Trump, while mocking international law, threatened to return Iran to the Stone Age and destroy a “whole civilization.”

Each side accused the other of initiating the escalation. Each strike was framed as retaliation. Each violation became justification for the next.

This is how norms collapse, not through formal repudiation, but through gradual normalization.

Had this trajectory continued, the consequences would have extended far beyond this war. The targeting of water infrastructure risked becoming an accepted instrument of statecraft — a precedent waiting to be replicated elsewhere.

In a warming world where water scarcity is intensifying, that is a profoundly destabilizing prospect.

The humanitarian and environmental consequences of hydro-warfare are stark.

Water scarcity unleashes cascading impacts. Hospitals are among the first to fail. Sanitation systems collapse, increasing the risk of disease outbreaks. Industrial sectors, from petrochemicals to data centers, grind to a halt, amplifying economic disruption.

The environmental risks are no less grave. Damage to desalination plants can release toxic chemicals into the Persian Gulf, while disruptions to brine discharge systems can create localized ecological “dead zones.” In a narrow, semi-enclosed body of water already under stress, such contamination could have long-term consequences for marine life — and for the seawater on which desalination depends.

Hydro-warfare also carries profound political implications. In the Gulf monarchies, state legitimacy rests on an implicit social contract: political acquiescence in exchange for stability and provision. Water is central to that bargain. If governments cannot guarantee basic supply — even under the umbrella of U.S. security protection — that contract begins to fray.

Iran appeared acutely aware of this dynamic. By targeting Gulf infrastructure, it sought not only to retaliate against U.S. and Israeli actions, but to drive a wedge between Gulf Arab states, which all host American military bases, and their Western patrons.

In short, the weaponization of water is self-destructive, even for those who imagine they gain short‑term leverage. It degrades the shared ecological foundation on which all communities depend.

Normalizing the unthinkable

What made the Iran war particularly dangerous was the convergence of three forces: deepening water stress, technological dependence and geopolitical confrontation.

Rising temperatures and erratic rainfall are intensifying water scarcity across the Middle East. At the same time, technological solutions like desalination have created new forms of dependency — systems that are efficient, even if costly, but fragile, centralized and exposed. War exploits that fragility.

The Iran conflict demonstrated how quickly these systems can be weaponized — and how difficult they are to restore once broken.

The targeting of water infrastructure marks a profound shift in warfare, extending conflict from the battlefield into the biological core of civilian life. What is at stake is not just the legality of certain tactics, but the survival of a foundational principle: that even in war, some things remain off-limits. That principle is no longer under strain; it is being dismantled.

If water can be weaponized with impunity, the distinction between combatant and civilian collapses. War ceases to be a contest between militaries and becomes an assault on the conditions of life itself.

TheUnited States and Israel may see these tactics as instruments of coercion, and Iran as tools of deterrence and retaliation. But all sides have participated in a dangerous experiment whose consequences will outlast the war.

The Middle East has long been a region defined by the politics of oil. It may now be entering an era shaped by the geopolitics of water. And unlike oil, water has no substitute. It is irreplaceable.

Brahma Chellaney is the author of two award-winning books on water: Water: Asia’s New Battleground and Water, Peace, and War: Confronting the Global Water Crisis.