More than Three-Quarters of Iran’s Land is Under Extreme Groundwater Overdraft

Over three-quarters of Iran’s land is experiencing severe groundwater overdraft, where the rate of human uptake is greater compared to the rate of natural recharge.

This was reported by a new study performed under the guidance of Concordia researchers and published in the Nature journal Scientific Reports.

Samaneh Ashraf, a former Horizon postdoctoral researcher who is currently working at the Université de Montréal, and Ali Nazemi, an associate professor in the Department of Building, Civil and Environmental Engineering, co-authored the article. Amir AghaKouchak of the University of California, Irvine, also contributed to the study.

The research team reports that the misgovernment by the authorities of the country is aggravating the present strains on the aquifers of the semi-arid country by an inefficient agriculture sector. They stated that without immediate action, the country experiences several 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,” stated Ashraf.

The researchers note that approximately 74 km³ of groundwater has been depleted from the 500 basins and sub-basins of the country from 2002 to 2015. This has led to increasing soil salinity and growth in land subsidence—fundamentally, land sinking.

The Salt Lake Basin is among a majority of the at-risk regions of land subsidence, including Iran’s capital Tehran, which is home to about 15 million people and already at risk of extreme seismic activity.

Human Role is Clear

The team utilized data that was available publicly, published by the Iranian Ministry of Energy, as the foundation for the study.

We wanted to quantify how much of Iran’s groundwater was depleted. Then we diagnosed why it was depleted. Was it driven by climate forces, by a lack of natural recharge or because of unsustainable withdrawal?

Ali Nazemi, Associate Professor, Department of Building, Civil and Environmental Engineering, University of Concordia

After analyzing all the available data, the team came to the conclusion that large agricultural demands were the overpowering major cause for the depletion of groundwater. The west, southwest and northeast part of the country, where farmers grow strategic crops such as barley and wheat, experienced the most extreme drops.

The study points out that the number of registered wells that extract groundwater for agriculture has virtually doubled in 10 years and 6 months, from about 460,000 in 2002 to approximately 794,000 in 2015. Anthropogenic groundwater withdrawals were reduced in 25 of the 30 basins of the country in the same period. This indicates that the aquifers are being overexploited by the activities of mankind.

The team analyzed soil electrical conductivity as a proxy for quantifying salinity levels throughout the country and discovered that they were also increasing.

Urgent Action Required

Adding to all these issues are governments at the local and national levels that are not empowered to tackle the increasing crisis for various reasons, such as local corruption, international sanctions, and general mistrust of authorities among the population. However, the researchers note that the country is in critical need of both short- and long-term solutions.

In the short term, the unregistered wells need to be shut down. But longer term, Iran clearly needs an agricultural revolution. This requires a number of elements, including improving irrigation practices and adopting crop patterns that fit the country’s environment.

Ali Nazemi, Associate Professor, Department of Building, Civil and Environmental Engineering, University of Concordia

Especially, while Iran is at risk as a result of its ineffective governance, increasing population, and natural surroundings, Nazemi cautions that its experiences provide warnings to other countries, such as Canada.

Iran’s example clearly shows that we need to be careful how we manage our water because one bad decision can have a huge domino effect. And if the problem is ignored, it will easily get out of control. It also illustrates the importance of environmental justice and stewardship. These are even more important when addressing the problem of climate change.

Ali Nazemi, Associate Professor, Department of Building, Civil and Environmental Engineering, University of Concordia

All three authors of the study are of Iranian origin and dedicated the paper to the people of Iran.

The study was financially supported by the Natural Sciences and Engineering Research Council of Canada (NSERC).

Video Credit: Concordia University.

Journal Reference:

Ashraf, S., et al. (2021) Anthropogenic drought dominates groundwater depletion in Iran. Scientific Reports. doi.org/10.1038/s41598-021-88522-y.

Source: https://www.concordia.ca/