In Southwest Tehran, the Land Subsidence Zone Has Grown by Up to 30 Percent

Ali Beitollahi, head of seismology and risk at the Road, Housing and Urban Development Research Center, told Mehr News Agency in an interview published on Friday, September 25, 2026 (3 Mehr 1405), that comparing the past two years with the two years before shows the subsidence zone in southwest Tehran has expanded by about 25 to 30 percent, and in Isfahan province by 20 percent. In Mashhad, he said, a zone that used to lie northwest of the city and outside its limits has now reached close to central parts of the city.

Beitollahi said subsidence has been documented in 30 provinces, all except Gilan, and that its main driver, excessive groundwater extraction, continues unchanged. The heaviest groundwater extraction takes place in Kerman, Razavi Khorasan, Fars, Isfahan and Tehran, he said, and these five provinces have the widest subsidence zones and the highest rates. He added that apart from local rainfall he sees no tangible action to reduce the risk. Subsidence affects the value and safety of buildings and urban infrastructure.