Lead
On Nov. 9, 2025, Iranian authorities began rationing water in Tehran as reservoirs that supply the capital fell to around 5 percent of capacity, officials said. The shortage comes amid the country’s worst drought in 60 years and a season in which Tehran recorded no autumn rainfall for the first time in a century. President Masoud Pezeshkian warned that if the drought lasts more than another month, the capital might need to be evacuated. Short-term measures include overnight pressure reductions and experiments with cloud seeding while officials urge both conservation and, in some cases, prayer.
Key Takeaways
- Tehran’s primary dams are at roughly 5% capacity, jeopardizing supply for more than 10 million residents dependent on those sources.
- Authorities have announced scheduled low-pressure periods from midnight to morning to cut leakage and allow reservoirs to refill, officials said on Nov. 9, 2025.
- Iran is experiencing its most severe drought in six decades and Tehran recorded zero autumn rainfall — a level unseen in 100 years according to officials.
- Groundwater over-extraction has led to subsidence of about 300 millimeters per year in parts of Tehran, a rate far above accepted safety thresholds.
- Officials have authorized cloud seeding but experts warn it requires clouds with at least ~50% moisture to be effective, a condition not currently met.
- Longstanding drivers include excessive dam building, illegal wells and unsustainable farming practices compounded by rising temperatures from climate change.
- President Pezeshkian has proposed moving the capital south toward the Persian Gulf and cautioned an evacuation could be necessary if the drought persists more than a month.
Background
Iran has long relied on surface dams and extensive groundwater extraction to irrigate agriculture and deliver urban water. Decades of expanding irrigation, construction of reservoirs and heavy groundwater pumping created a system vulnerable to low precipitation. Experts point to poor coordination among agencies — some build dams while others seek agricultural expansion — which has intensified depletion of aquifers.
Climate change has increased average temperatures across the region and altered precipitation patterns, making droughts longer and more intense. The current event is described by Iranian officials as the worst in 60 years; Tehran’s autumn without measurable rain is described as a century-first for the capital. Sanctions and political isolation have also limited access to some international technologies and investment that could help modernize water management.
Main Event
Officials for Tehran’s water network announced this week that the main dams supplying the city were at about 5 percent of capacity and said they would reduce mains pressure overnight to curb leaks and allow local reservoirs to recover. The water industry spokesman, Isa Bozorgzadeh, told reporters the pressure reduction would run from midnight until morning as a temporary conservation measure.
The Ministry of Energy has begun cloud-seeding operations dispersing particles such as silver iodide into existing clouds; ministry statements and state-affiliated outlets characterized this as an emergency response. Scientists caution that cloud seeding can only augment rain when clouds already carry substantial moisture, a condition reportedly absent this season.
President Masoud Pezeshkian has repeatedly raised the severity of the crisis and, on Nov. 9, 2025, said that if the drought continues for more than a month, Tehran may require evacuation. He has also floated relocating the capital toward the Persian Gulf to access open waters, though officials have not published a plan for how any evacuation or relocation would be implemented.
Analysis & Implications
The immediate implication is a humanitarian and logistical strain on Tehran’s more than 10 million residents: reduced household water availability, increased competition for remaining supplies and heightened risk to health and sanitation systems. Overnight pressure cuts may conserve volume in the short term but do little to address structural losses from leaky networks and illegal wells.
Economically, prolonged water scarcity will pressure agricultural output, raise food prices and strain energy systems as power cuts have already accompanied high temperatures. Ground subsidence at the reported rate of roughly 300 millimeters per year threatens infrastructure and increases repair costs for roads, buildings and utilities.
Strategically, the crisis highlights governance gaps: agencies pursuing dams, agricultural expansion and conservation simultaneously without coordinated planning. Modern water management—drip irrigation, crop switching, metering, groundwater regulation and leak detection—could reduce demand substantially but requires investment, data systems and cross-agency cooperation.
Internationally, Iran’s isolation complicates adoption of high-resolution satellite monitoring, AI-driven water management tools and the finance needed for large-scale reforms. Unless external barriers ease or domestic policy pivots rapidly, experts warn the drought will accelerate rural-to-urban migration, undermine food security and raise the likelihood of politically sensitive emergency measures.
Comparison & Data
| Metric | Reported Value |
|---|---|
| Main dams feeding Tehran (capacity) | ~5% |
| Population dependent on those dams | >10 million |
| Tehran ground subsidence | ~300 mm per year |
| Autumn rainfall in Tehran | None recorded (first time in ~100 years) |
The table summarizes figures cited by Iranian officials and experts. These diagnostics show both acute supply shortfalls and chronic stresses such as subsidence that reduce resilience. Quantitative tracking of reservoir levels, groundwater decline and consumption per sector would be needed to prioritize actions.
Reactions & Quotes
Officials have mixed technical steps with public appeals. The water industry spokesman described operational measures to conserve supply, while political leaders discussed contingency scenarios including relocation and evacuation. Religious and municipal figures have also urged traditional measures such as public prayers for rain.
“We will lower water pressure from midnight until morning to reduce urban leakage and give reservoirs a chance to refill.”
Isa Bozorgzadeh, Iran water industry spokesman
Bozorgzadeh framed the overnight interruptions as a technical mitigation to slow immediate losses. State-affiliated outlets reported some neighborhoods already experienced multi-hour nightly cuts, prompting local concern about continuity of service.
“If this drought persists more than a month, we’ll have to evacuate Tehran.”
Masoud Pezeshkian, President of Iran
The president’s statement underscored the political stakes but left logistics unspecified. Observers say an evacuation for water reasons in a megacity would be unprecedented and would require detailed planning that so far has not been published.
“Alongside all other measures, we should not neglect going out to pray for rain.”
Mehdi Chamran, Head of Tehran City Council
Chamran’s appeal reflects a blend of civic and religious responses; some municipal leaders encouraged traditional rain-prayer gatherings while also urging conservation and technical fixes.
Unconfirmed
- Claims that neighboring states are “stealing” Iran’s rain clouds lack evidence and remain unverified by independent meteorological agencies.
- Details and feasibility of a planned evacuation of Tehran have not been released; there is no public evacuation timetable or operational plan available.
- The effectiveness of current cloud-seeding efforts this season is uncertain because independent humidity measurements indicating the necessary cloud moisture threshold (~50%) have not been released.
Bottom Line
Tehran’s emergency water rationing reflects both an acute meteorological shock and long-term mismanagement of water resources. Short-term measures such as pressure reductions and cloud seeding may marginally ease supply but do not address the structural decline of aquifers, leaky networks and unsustainable agricultural demand.
Meaningful relief will require coordinated policy across ministries, investment in efficient irrigation and urban infrastructure, transparent data on reservoir and groundwater trends, and—where possible—access to advanced monitoring technologies. Without substantial reforms or a change in the external constraints that limit technology and finance, Tehran and other Iranian regions face prolonged water stress with social, economic and infrastructural consequences.
Sources
- The New York Times (press report summarizing official statements and field reporting)
- Tasnim News Agency (state-affiliated news outlet reporting on local water cuts)
- Tabnak (state-affiliated news outlet reporting regional service interruptions)
- Agence France-Presse (international news agency; photo and regional reporting)
- Hamburg University of Technology (TUHH) (academic institution associated with cited water and soil expert commentary)