A study has confirmed that saltwater is penetrating deep into the ground, threatening farms, driving sinkholes and infiltrating freshwater aquifers in the Jordan Rift Valley, a fertile agricultural area that stretches along the Jordanian border.
Scientists found that saline water is seeping through ravines and geological faults in the valley, reaching a depth of about 100 metres and extending up to 1.75 kilometres into the shallow aquifer, an underground layer of rock that stores water near the earth’s surface.
“The trees on my farm are not growing, their leaves are yellow, and their yield is so low that even the taste of the fruit has changed.”
Jordanian farmer Dhabia Al-Ghazzawi
Jafar Abu Rajab, a lecturer in the department of earth and environmental science at
Jordan’s Hashemite University, says this could have profound implications.
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“The Dead Sea is a unique natural laboratory and any small change in the balance between its salt water and the fresh groundwater around it can have dramatic consequences on land,” he tells SciDev.Net.
Sinkholes
The most severe salinity intrusion occurred in the Wadi Bin Hammad valley, northwest of the city of Karak in Jordan, where the water seepage extends parallel to an active strip of sinkholes, which have swallowed up agricultural areas and cut off roads.
The researchers say it reveals a direct link between the seepage and the sudden appearance of sinkholes on the surface.
The study, published in the journal Scientific Reports, is the first to document these leakage paths. It includes new maps prepared using advanced electromagnetic imaging technology, which researchers say captures the movement of hidden saltwater underground, as well as being faster and less costly than other methods.
The Dead Sea, which borders Jordan to the east and Israel and the West Bank to the west, has been receding for decades at a rate of more than one metre per year. This has lead to the erosion of its shoreline and the collapse of the fragile balance between saltwater and freshwater.
Map showing location of the Dead Sea in Jordan. Adapted from Wikimedia Commons. (CC BY-SA 4.0).
“The sinkholes – which appeared as a result of this imbalance – swallowed fields and roads, and new streams carved their way through the mud, forcing farmers to abandon their land despite repeated attempts to fill in the sinkholes and repair the land without success,” says Abu Rajab.
“The situation regarding groundwater remains unclear, due to the lack of accurate official data on specific wells or their salinity levels. However, farmers rely on surface wells for irrigation, and there are increasing signs of salinisation in the absence of regular monitoring.”
Crop losses
According to Abu Rajab, there are currently no official Jordanian sources accurately showing the extent of agricultural losses or changes in groundwater quality.
However, Jordanian farmers say they are already feeling the impacts of saltwater seepage on their crops.
Dhabia Al-Ghazzawi, a member of Jordan’s women farmers’ union, tells SciDev.Net: “The salinity of the Dead Sea has increased the salinity of the soil and affected the water in the wells, killing our trees and reducing our harvest, making our farming no longer viable.
Dhabia Al-Ghazzawi at her garden near the Dead Sea. Photo courtesy of Dhabia Al-Ghazzawi.
“The trees on my farm are not growing, their leaves are yellow, and their yield is so low that even the taste of the fruit has changed.”
She adds that while some farmers are trying to cope with the crisis with limited means, many have no choice but to leave their land.
“Those who have the financial means try to mitigate the situation with additional irrigation or soil testing, but most farmers have been forced to leave their land due to agricultural and financial losses,” she says.
The impact of the phenomenon is not limited to farms. Abu Rajab points out that the damage has spread northwards to hotels and resorts on the Dead Sea coast, where sinkholes and landslides have damaged roads and infrastructure, requiring costly repairs to ensure the continuation of tourist activity.
Al-Ghazzawi says this has also affected young people, impacting on job opportunities and wages and worsening living costs for families in the region.
Reducing risks
The research team carried out 195 field measurements over an area of 12 square kilometres in Ghor Al-Haditha, on the eastern shore of the Dead Sea in Jordan, producing accurate maps of the salt intrusion paths.
Abu Rajab says the maps provide an early warning tool that helps communities avoid digging wells in dangerous areas and directs water projects to a safer location.
“They also enable decision-makers to protect drinking water sources and guide water policies, rather than waiting for disaster to strike,” he adds.
Karem Abdelmohsen, a research associate at the School of Sustainability at Arizona State University, in the US, who was not involved in the study, says it showed that shallow groundwater is most affected, while deep groundwater remains less threatened.
He says it also linked intrusion pathways to geological structures such as faults, revealing their role in accelerating the movement of saline water.
However, he points out that “relying solely on physical measurements for mapping requires supporting the results with chemical analyses of well water or additional geophysical methods to increase accuracy, especially at greater depths”.
Osama Sallam, water projects manager at the Environment Agency-Abu Dhabi, who also had no role in the study, says the findings make a valuable contribution to sustainable agriculture, providing accurate data on the overlap of saltwater and freshwater and making recommendations to drill monitoring wells to reduce risks.
Abdulmohsen and Sallam agree that what has been documented in the southern Dead Sea could have wider implications for the Arab region.
Areas such as the Nile Delta in Egypt or the Persian Gulf coast face similar challenges, where excessive pumping and rising sea levels due to climate change are accelerating the encroachment of salinity into groundwater.
Abdulmohsen adds: “Using the same study methodology in other areas will help identify the points most vulnerable to climate change and sea level rise and develop effective resource management policies.”
This article includes contributions from Najat Shannaa, SciDev.Net correspondent in Jordan, through the inclusion of comments from farmer Dhabia Al-Ghazzawi.
This piece was produced by SciDev.Net’s Middle East and North Africa desk.
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