Tehran confronts a water crisis so severe that Iranian officials have warned the capital of 16 million people may need partial evacuation if shortages intensify, a potential catastrophe rooted in revolutionary-era population policies colliding with decades of infrastructure neglect.
Iran's population exploded from approximately 21.5 million in 1960 to 91.6 million in 2024, while Tehran itself grew from under one million residents to roughly nine million within city limits—16 million including the greater metropolitan area. This dramatic expansion, distinct from global demographic trends, stems directly from policy decisions made in the early years of the Islamic Republic.
After the 1979 revolution, Ayatollah Khomeini suspended family planning programs instituted under the Pahlavi monarchy, encouraging large families as part of an ideological commitment to building a powerful Islamic state through population growth. The policy achieved its demographic objective: Iran's birth rate in the 1980s ranked among the world's highest, with women averaging more than six children.
The consequences of that policy now strain every aspect of Iranian urban infrastructure. Tehran's water supply system, designed for a fraction of its current population, struggles to meet demand even in normal years. Climate change has compounded the crisis, with prolonged droughts reducing snowpack in the Alborz Mountains that supply much of the capital's water.
Tehran's water shortage represents perhaps the most acute manifestation of Iran's infrastructure collapse, but it is far from the only one. Housing strain, traffic congestion reaching dystopian levels, air pollution among the world's worst, and overwhelmed schools and hospitals all trace back to a population that grew faster than the systems meant to support it.
The gap between births and deaths—the natural increase rate—remains the primary driver of Iran's population growth, though the rate has slowed dramatically since the 1990s when the government reversed course and implemented aggressive family planning campaigns. Iran's fertility rate has since plummeted to below replacement level, but the demographic momentum from the high-birth-rate decades continues to add millions to the population.
For Tehran specifically, the water crisis has reached critical thresholds. The city relies on a combination of surface water from rivers and reservoirs, and groundwater from aquifers that are being depleted far faster than they can naturally recharge. Reports indicate that groundwater levels in some areas around Tehran have dropped by more than 50 meters over recent decades.
Iranian officials have floated various proposals to address the crisis, from desalination plants (technologically complex and energy-intensive for an inland city) to massive inter-basin water transfer projects that would pipe water hundreds of kilometers from other regions. None offers a near-term solution, and all require financial resources that Iran's sanctions-battered economy struggles to marshal.
The prospect of evacuating portions of Tehran—a scenario Iranian environmental officials have publicly discussed—would represent an unprecedented urban crisis. Where would millions of displaced residents go? How would the economic heart of Iran continue to function? The questions remain unanswered, even as the water situation deteriorates.
In this region, today's headline is yesterday's history repeating. The Islamic Republic's early population policies, implemented with ideological fervor and little consideration for resource constraints, have created a demographic trap that now threatens the viability of Iran's capital city.
The Tehran water crisis also highlights the broader challenge facing Iran's governance system: an inability to make long-term infrastructure investments that match population growth. Decades of international sanctions, mismanagement, corruption, and the prioritization of military and proxy expenditures over domestic infrastructure have left Iranian cities unable to provide basic services to their residents.
Ordinary Iranians increasingly recognize that their water crisis stems not primarily from climate change—though that exacerbates the problem—but from policy failures dating back decades. On Iranian social media, activists point to the water-intensive agriculture encouraged by government subsidies, the sprawling construction of water-guzzling projects with dubious utility, and the Revolutionary Guard Corps' control over water resources as evidence of systemic governance failure.
The water shortage has already triggered protests in several Iranian cities, with demonstrations in Isfahan and Khuzestan turning violent as citizens demanded access to basic water supplies. As Tehran's situation worsens, the political implications of water scarcity in the capital could prove destabilizing for a regime already facing mounting domestic discontent.
Iran's experience offers a cautionary tale about the long-term consequences of ideologically driven demographic policies divorced from resource planning. The children born during the 1980s baby boom are now adults navigating a country whose infrastructure cannot support them—a direct result of decisions made four decades ago that are only now revealing their full consequences.
