More than three quarters of Iran’s land is under extreme groundwater overdraft, where the rate of human uptake is higher than the rate of natural recharge. This is according to a new study led by Concordia researchers published in the Nature journal Scientific Reports.
The article was co-authored by Samaneh Ashraf, a former Horizon postdoctoral researcher now at the Université de Montréal, and Ali Nazemi, an associate professor in the Department of Building, Civil and Environmental Engineering. Amir AghaKouchak of the University of California, Irvine, also contributed to the paper.
The researchers write that mismanagement by the country’s authorities is exacerbating existing strains on the semi-arid country’s aquifers by an inefficient agriculture industry. Without urgent action, they note, the country faces multiple national crises.
“The continuation of unsustainable groundwater management in Iran can lead to potentially irreversible impacts on land and the environment, threatening the country’s water, food and socioeconomic security,” Ashraf says.
The authors write that an estimated 74 km3 of groundwater has been depleted from the country’s 500 basins and sub-basins between 2002 and 2015. This has contributed to both growing soil salinity and an increase in land subsidence — basically, land sinking. Among the most at-risk regions of land subsidence is the Salt Lake Basin, which includes Iran’s capital Tehran, home to some 15 million people and already at risk of severe seismic activity.