Amid serious warnings about land subsidence across Iran, a member of Tehran City Council has said the situation is “hazardous” in a few regions of the capital.
The deputy head of the environmental protection committee of the capital’s City Council, Mehdi Babaee, told ILNA on Sunday that ground subsidence in the southwestern districts of Tehran has reached a dangerous level, to about 20 centimeters per year.
"We are developing a plan in Tehran city council, according to which the municipality will be required to use surface water recycling for water consumption in urban areas, including irrigation of green spaces,” he said, noting that the implementation of such a plan can lead to a reduction in the extraction of the capital's underground water resources and reduce the rate of land subsidence in the city.
According to the latest official data by the geological organization of the country, the rate of subsidence in the plains around Tehran was between 17 and 24 centimeters per year.
Tehran is facing a serious problem of rapid ground subsidence due to decreasing ground water levels, imagery consulting firm Intel Lab reported in July 2021. Intel Lab published a series of satellite imagery showing relative levels of sinking ground between January 2020 and April 2021. In some areas the ground had sunk up to 25 centimeters or more than 8 inches.
Depletion of underground water is one of the main causes for ground subsidence that can threaten not only cities but also agricultural lands. Moreover, land subsidence is not limited to cities and their surrounding plains. In many other areas in Iran cracks and huge hollows that resemble meteor craters have appeared in the ground in recent years.
A huge sink hole that suddenly appeared in central Iran. Undated
Ali Saberi, a geologist, said last year that one million hectares of land in the country is affected by subsidence, blaming unlimited extraction of ground water as the main cause of the phenomenon.
Alireza Shahidi, the head of Iran’s Geological Organization said in 2021 that land subsidence is a “disaster” and a “silent earthquake” that can lead to political and security crises.
Iran’s natural disaster taskforce says 20 million urban residents face ground subsidence in 29 of 31 provinces, warning about agricultural overuse of water. Ali Beytollahi, the head of the taskforce said Iran has not come up with policies and rules to deal with the disaster, as drought and wasteful irrigation methods are depleting groundwater reserves, adding that unless serious action is taken, the country can soon reach a point of no return.
According to experts, the country has less than ten years to deal with dangerous land subsidence because of over-extraction of ground water.
According to Gholam-Ali Jafarzadeh, the head of the National Cartography Center, 80 percent of the groundwater is withdrawn annually in Iran, adding that over the past decades, some of the aquifer levels dropped by 100 centimeters.
In addition to Inefficient irrigation methods, digging illegal wells is the other cause of subsidence, as out of 50,000 wells pumping underground water resources in the capital, 30,000 are illegal.
Iran has been suffering from drought for more than a decade and this year lack of precipitation is larming. Over the next 40 years, the country's temperature will rise by 2.6 degrees Celsius, which will make matters worse.
As drought persists, more underground water is exploited for irrigation, depleting natural reservoirs formed during thousands of years. This has aggravated ground subsidence, alarming government officials who have circulated confidential memos on the subject.