Land subsidence has expanded into a nationwide crisis affecting nearly half of Iran’s population, with parliamentary researchers warning the damage could become irreversible if current trends continue, Shargh newspaper reported on Monday.
Around 39 million people, or about 49% of Iran’s population, live in areas affected by land subsidence or at risk of its expansion, according to the latest report by the Iranian parliament’s research center cited by Shargh. The report said the phenomenon now covers about 185,000 square kilometers, nearly 11% of the country’s land area.
“Land subsidence is no longer confined to a handful of plains or isolated regions and has become a national crisis that threatens Iran’s territorial security and development outlook,” Shargh wrote, citing the parliamentary findings.
More than 380 cities and 9,200 villages are located in affected areas or in zones where subsidence is expected to spread, underscoring the scale of the challenge.
Groundwater depletion drives crisis
The parliamentary research center identified excessive groundwater extraction as the primary cause of land subsidence, with declining rainfall and prolonged drought accelerating the process.
As underground aquifers are depleted, soil layers compact and the ground sinks, a process that is often irreversible and permanently reduces the aquifers' capacity to store water, the report said.
The findings warned that subsidence poses a growing threat to roads, railways, water, gas, electricity and telecommunications networks, as well as residential buildings and historical monuments.
The report also said the phenomenon carries broad economic, social and public health consequences by increasing infrastructure maintenance costs, reducing property values, disrupting economic activity, degrading water quality and encouraging migration.
Recent reports have highlighted land subsidence as an increasing risk to some of Iran’s historical sites.
In September 2025, earthquake expert Mehdi Zare warned Iran was heading toward an “urban catastrophe” because of worsening land subsidence. Three months later, National Cartographic Center chief Eskandar Seydaiee said every part of the country except the Caspian Sea coastal provinces was experiencing subsidence to varying degrees.
Tehran faces the highest risk
Tehran is Iran’s most severely affected province, with about 1,630 square kilometers – roughly 12.5% of its area – already experiencing land subsidence, Shargh said.
The main hotspots are the Varamin plain and southwestern parts of the province, including Tehran municipal districts 17, 18, 19 and 21, along with the cities of Eslamshahr, Shahriar and Malard.
The report attributed the capital’s worsening conditions largely to concentrated overuse of groundwater resources.
Groundwater, it said, supplied about 26% of Tehran’s water at the beginning of the 2010s but now accounts for around 45%. Other estimates suggest dependence is even higher, with 62% of the capital’s water drawn from underground aquifers and only 38% from surface sources.
The findings come after Iranian officials warned this month that six consecutive years of drought, falling rainfall and dwindling renewable water resources have left Tehran facing a deepening water supply crisis, adding to concerns that continued overexploitation of groundwater will intensify land subsidence across the country.
