• Fissures appear along roads while massive holes open up in the countryside, their gaping maws a visible sign from the air of something Iranian authorities now openly acknowledge — the area around Tehran is literally sinking.
  • Stressed by a 30-year drought and hollowed by excessive water pumping, the parched landscape around Iran’s capital has begun to sink dramatically.
  • Tehran, which sits 1,200m (3,900 feet) above sea level against the Alborz Mountains on a plateau, has rapidly grown over the last 100 years to a sprawling city of 13 million people in its metropolitan area.
  • All those people have put incredible pressure on water resources on a semi-arid plateau in a country that saw only 171 mm (6.7 inches) of rain in 2018.
  • Over-reliance on ground aquifers has seen increasingly salty water pumped from below ground.
  • Surface soil contains water and air. When you pump water from under the ground surface, you cause some empty space to be formed in the soil
  • Gradually, the pressure from above causes the soil particles to stick together and this leads to sinking of the ground and formation of cracks.
  • Over the past decade, Iran has seen the most prolonged and severe drought in more than 30 years, according to the United Nations’ Food and Agriculture Organisation.
  • An estimated 97% of the country has faced some level of drought, Iran’s Meteorological Organisation says.
  • That has caused the sinkholes and fissures now seen around Tehran.
  • The sinking also threatens vital infrastructure, like Tehran’s Imam Khomeini International Airport. German scientists estimate that land under the airport is sinking by 5 cm (1.9 inches) a year.
  • Tehran’s oil refinery, a key highway, automobile manufacturing plants and railroads also all sit on sinking ground, said Ali Beitollahi, a Ministry of Roads and Transportation official.
  • Geopolitics play a role in Iran’s water crisis.
  • Since the country’s 1979 Islamic Revolution, Iran has sought to become self-sufficient across industries to thwart international sanctions.
  • That has included agriculture and food production.