Should the war over Iran grind on, water may become as crucial a commodity as oil. The arid Arab countries of the Gulf increasingly rely on desalination, which provides 90% or more of the drinking-water supply for Bahrain, Kuwait and Qatar, and almost as much for Oman. For Saudi Arabia it is 70%, and roughly 40% in the United Arab Emirates (UAE).

This has created a “dangerous new bunch of vulnerabilities” for Gulf countries, says Peter Schwartzstein of the Stimson Centre, an American think-tank. Their rapidly expanding populations and thirsty industries now rely on the smooth running of “a handful of bits of water infrastructure”, he explains. These Arab countries depend on thousands of plants; the most productive of which line the coast (see map). That puts them within easy reach of Iranian missiles and drones.

The risks during war are obvious. An American diplomatic cable written in 2008 and published by WikiLeaks noted that the Jubail Desalination Plant alone then supplied Riyadh, the kingdom’s capital, with over 90% of its drinking water. If its pipelines or the power infrastructure around it were hammered, the city would have to be evacuated within a week. If that were to happen, the memo concluded, “the current structure of the Saudi government could not exist”.

Since 2006 the Gulf states have spent around $53bn to offset this risk. Saudi Arabia now gets roughly 40% of its desalinated water from smaller facilities that are more spread out. Abu Dhabi and Qatar are building up strategic reserves. Thanks to these investments, most Gulf countries have a modicum of protection. Even if Iran did hit the plants, in most countries some drinking water would continue to flow.

But huge gaps remain. Most of the Gulf’s desalinated water comes from a small number of plants. Storage is patchy: the UAE aims to have reserves equivalent to just two days of normal consumption by 2036, which could be stretched to around a month by strict rationing. Smaller states like Bahrain are even more exposed.

Attacking civilian water infrastructure is generally considered a war crime. It may already have been perpetrated by both sides in this conflict. American forces reportedly struck a plant on Iran’s Qeshm Island; Iran then hit one in Bahrain. Shortly before Donald Trump abruptly changed tack on his threat to clobber Iranian power plants, Iran’s Islamic Revolutionary Guard Corps said it would target Gulf countries’ water facilities in response.

Though Iran relies much less on desalination, it is desperately short of water. Decades of building dams and recklessly extracting water have depleted supplies. Almost a third of Iranians face shortages. And the war will do little to help Iran’s already modest co-operation on water with nearby countries. As the conflict goes on, Iran may turn off the taps for its Gulf neighbours. But it is increasingly likely to run out of water itself. ■

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