More than 800 towns and villages, including the capital Tehran and the major city of Isfahan, are at risk from land subsidence, Iranian authorities say.
The ground beneath Tehran sinks by up to 22 centimeters (around 9 inches) every year, which is seven times higher than what would be normally expected.
The reason, experts say, is the country's acute water shortage.
"This is a serious crisis affecting at least half of Iranian society," said Roozbeh Eskandari, a Canadian-based expert on a hydraulic structures and dam construction.
Eskandari has long since warned about the consequences of Iran's water scarcity.
"Land subsidence resulting from unsustainable water consumption endangers the country's entire infrastructure, including pipelines, power lines and railroads," Eskandari told DW.
"There is an urgent need to find and correctly implement long-term solutions. Iranian authorities are relying on the fact there will eventually be sufficient rainfall to solve the dwindling water reservoir problem."
Iran has in fact seen more rain in recent months than in previous years. But what could have been a blessing turned out to be a curse. Heavy rainfall caused flooding........