Chapter 21

Basalt Aquifer System (West)

Yarmouk Basin

Executive Summary 

The Yarmouk Basin constitutes the western section of the Basalt Aquifer Complex. It extends between the Jebel al Arab Mountain, the Hauran Plateau and the south-eastern foothills of Mount Hermon. In the south-west, the Basalt Aquifer stretches into the Golan Heights to Lake Tiberias.

Groundwater flow is generally directed from topographically higher catchments to the major discharge zone around Wadi Hreer-Mzeirib in the Yarmouk Basin, while the western part of the Golan Heights drains towards Lake Tiberias. Groundwater discharge in the Yarmouk Basin appears to be largely maintained by present-day recharge over wide catchment areas, with travel periods of several thousands of years. The main aquifer system in the basin comprises permeable layers in Neogene-Quaternary basalts and the underlying sedimentary rocks (Paleogene and/or Upper Cretaceous formations, depending on the lithostratigraphy of the sequence), which are hydraulically connected with the basalts.

Groundwater and surface water are closely interlinked in this region and the Basalt Aquifer constitutes an important source of water for the Yarmouk River and the Jordan Basin as a whole. Large-scale expansion of groundwater abstraction in some parts of the Yarmouk Basin is likely to have affected natural flow and discharge patterns within a larger radius and may have contributed to the hydrological decline of the Yarmouk River. This has long been a point of conflict between Jordanian and Syrian authorities.

  • Basalt Desert, Jordan, 2005. Source: Robert Bewley, Aerial Photographic Archive for Archaeology in the Middle East.
  • View of Lake Tiberias and the Golan Heights from Jordan, 2011. Source: Tamra Hays.
  • Lake Tiberias, Israel, 2010. Source: Adam Groffman.
  • Mount Hermon in the Golan Heights, Syria, 2008. Source: Adel Samara.
  • Lake Tiberias, Israel, 2010. Source Adam Groffman.

Basin Facts 

Riparian Countries Jordan, Syria
Alternative Names --
Renewability High
Hydraulic Linkage with Surface Water Medium (20-100 mm/yr)
Rock Type Fractured to mixed
Aquifer Type Unconfined
Extent ~7,000 km2
Age Neogene-Quaternary, Paleogene (Upper Cretaceous)
Lithology Basalt, limestone
Thickness <100 m - >300 m
Average Annual Abstraction --
Storage --
Water Quality Mainly fresh
Water Use Agricultural and domestic
Agreements Groundwater-related provisions in the 1987 agreement regarding the utilization of the waters of the Yarmouk River
Sustainability Over-exploitation of groundwater, reduced spring flow in discharge zone, local groundwater pollution