Jordanian-Syrian Relationship Transformations: The water relationship between Jordan and Syria has undergone a notable transformation — it was tense during Bashar al-Assad's rule due to water depletion, but has seen improvement and new understandings with the new Syrian administration led by Ahmad al-Sharaa, aimed at achieving fair water redistribution.

Israeli Control and Its Repercussions: Israel controls strategic areas in the Yarmouk Basin, including parts of the main water sources and the Unity Dam, significantly affecting Jordan's and Syria's water shares and adding to the region's water challenges.

Jordan Facing a Chronic Water Crisis: Jordan suffers from acute water poverty and is considered one of the world's most water-scarce countries. This situation has been worsened by population pressure and refugee influxes, making the management of Yarmouk Basin waters vital to its water and food security.

The Yarmouk River Basin is a vital water artery shared by Jordan, Syria, and the Israeli occupation, forming a focal point for ongoing regional tensions and conflicts over water resources. The basin's importance goes beyond being a water source — it represents a geopolitical factor influencing relations among all three parties.

Recent decades have witnessed dramatic shifts in how its waters are managed and distributed, shaped by political conflicts, regional changes, and growing environmental pressures. Understanding these dynamics requires a historical and contemporary review of water relations, with a focus on recent developments on the Syrian scene and their impact on the region's water security.

The Yarmouk Basin covers an area of approximately 8,000 square kilometers and represents a major tributary of the Jordan River. The river contributes up to 40% of Jordan's surface water supplies and is essential for the King Abdullah Dam, which covers 70% of the irrigation needs in the Jordan Valley. Historically, the river's annual flows ranged between 400–500 million cubic meters, but have seen a significant decline in recent years, dropping to less than 200 million cubic meters annually due to drought and overuse. These figures underscore the basin's vital importance to the water and food security of the riparian states.

Historical Water Relations and Disputes

The roots of water relations between Jordan and Syria date back to agreements in the 1950s, later revised in 1987. These agreements stipulated water distribution and the establishment of joint projects, including the construction of water storage dams. However, the former Syrian regime under Bashar al-Assad did not fully comply with these provisions, especially after 2011 with the outbreak of the Syrian war. Estimates suggest that Syria was draining no less than 330 million cubic meters annually from the Yarmouk Basin before 2011 — three times its allocated share.

During Bashar al-Assad's rule, tensions escalated significantly. Jordan accused the Syrian regime of diverting Yarmouk waters, leading to a 50% reduction in water flow to Jordan by 2015. These violations included the construction of a large number of dams and reservoirs on the Yarmouk's tributaries, as well as the drilling of thousands of groundwater wells that severely depleted the basin. Tensions peaked between 2014 and 2020, when flow dropped to 100 million cubic meters due to the construction of the Syrian Unity Dam, which held back 150 million cubic meters for irrigating Al-Hasakah — negatively impacting Jordan's agreed share of 217 million cubic meters per year.

Improvement Under the New Syrian Administration Led by Ahmad al-Sharaa

Following the fall of the Assad regime in December 2024 and Ahmad al-Sharaa's assumption of power in Syria, water relations saw a notable improvement. In January 2026, al-Sharaa and Jordan's water minister signed a preliminary agreement to redistribute Yarmouk waters, aiming to increase Jordan's share to 180 million cubic meters per year. This agreement represents an important step toward "fair distribution" of water, with the reactivation of the joint technical committee that had been dormant for years. The agreement also includes cooperation in combating smuggling and technological exchange for water management, reducing tensions by 60% compared to the Assad era. These developments have generated Jordanian optimism about achieving greater water sustainability through cooperation with the new Syrian leadership.

Israel's Theft of Yarmouk Basin Waters

Israel is considered a key active party in the dispute over Yarmouk Basin waters, repeatedly accused of "stealing" water resources. Israel occupies strategic areas in southern Syria, including parts of the Yarmouk Basin, its dams, and other sources in the Quneitra region. This control gives it the ability to regulate the river's flow and its most important freshwater sources, directly affecting water supplies for both Syria and Jordan.

The Impact of Israeli Control

The accusations of "theft" include Israel's control of the Tiberias Dam, which holds back 80% of upstream flows — reducing Jordan's share from the Yarmouk to only 120 million cubic meters, compared to the 200 million cubic meters needed. Additionally, Israel depletes groundwater in the Wadi Araba area, affecting 15% of Yarmouk supplies. Some studies indicate that these practices have led to the contamination of 40% of the river's water with Israeli wastewater. Even the 1994 Jordanian-Israeli Peace Agreement (the Wadi Araba Treaty), which set Jordan's share of the Jordan River at 50 million cubic meters per year, did not address the Yarmouk directly — drawing Jordanian criticism over the failure to guarantee full water rights.

Jordan faces a chronic water crisis, with the kingdom's per capita water share among the lowest globally at approximately 60–61 cubic meters per year. This situation is further complicated by Jordan hosting millions of refugees, placing additional pressure on the already scarce water resources.

Jordan's annual water consumption stands at approximately 1.2 billion cubic meters, while supplies do not exceed 900 million cubic meters as of April 2026, indicating a significant deficit. The Yarmouk Basin covers 25% of these supplies. Compounding this is considerable population pressure, with a total population of 11 million, including 2 million refugees, further increasing water demand. Agriculture consumes approximately 50% of the water — a vital sector that relies heavily on Yarmouk waters, irrigating 40% of agricultural land.

National Strategies and Diversified Sources

Jordan's National Water Strategy through 2026 aims to reach 1.1 billion cubic meters of water through diversification of sources. This "risk diversification" model relies on local desalination (such as the Aqaba project targeting 250 million cubic meters), groundwater (such as the Disi aquifer), and regional imports (such as importing 100 million cubic meters from Israel). Despite the heavy rainfall season Jordan recently experienced in 2025 — which raised water storage to 60% of capacity — water scarcity remains a chronic challenge requiring continuous management and sustained effort. Pollution also remains a challenge, with 30% of water unfit for consumption.

Summary of Water Challenges and Opportunities

This table illustrates the main water challenges and potential opportunities for cooperation in the Yarmouk Basin, focusing on Jordan's relations with Syria and Israel.

Israel's control over drinking water sources in southern Syria, including the Yarmouk Basin, has profound implications for water security across the entire region. This control allows Israel to significantly influence water flows to both Jordan and Syria, further compounding the water scarcity challenges facing both countries.

The Yarmouk Basin therefore remains a pivotal issue in regional water security, and recent political developments in Syria provide an opportunity to reshape the water dialogue and modernize distribution and monitoring mechanisms. Nevertheless, Israel's control over water sources in southern Syria remains a fundamental concern for Jordanian and Syrian water security, and the situation demands a lasting agreement that guarantees sustainable and equitable water flows for both countries, upholds the integrity of previous agreements, and addresses the challenges arising from war and political change.

The Yarmouk River Basin represents more than just a water resource — it is a confluence of regional politics, historical conflicts, and future aspirations. While Jordanian-Syrian relations have seen notable improvement under the new Syrian administration, inspiring hope for more equitable resource distribution, the challenges posed by Israeli control over vital parts of the basin remain and continue to threaten the region's water security. Confronting these challenges requires not only sustainable water agreements, but also strong political will from all parties to ensure stability and prosperity for the millions of people who depend on this vital lifeline.