Surface Water

Yarmouk River at Adasiyia

Yarmouk River at Adasiyia near its confluence with Jordan River

Flow characteristics of the Yarmouk River at Adasiyia, at an elevation of 212 m below sea level, have been measured since about 1964. The watershed area at the gage is 6,790 km2, 14% larger than at the upstream gage at Maqaren. However, the flow is affected by diversions between the Adasiyia and Maqaren sites as seen by comparing the annual volume graphs for these sites on this and the previous page. Although the median annual volume (203 MCM) for these sites is nearly equal when computed for the entire period of record, annual volumes prior to 1967 were higher at Adasiyia than Maqaren, as expected for a condition prior to diversions. Since about 1971, annual volumes at Adasiyia have been much less than upstream at Maqaren during relatively dry years (when diversions can account for a large percent of the flow), but have been much higher than at Maqaren during wet years (when diversions account for only a small percentage of the flow). Similarly, the median monthly volume at Adasiyia is less than at Maqaren for all except the highest runoff months of January, February, and March.

Typical monthly flows at Adasiyia are between 4 and 5 MCM during the dry season and between 17 and 40 MCM during the winter months. The maximum known flood occurred in February 1992, and produced a peak discharge of 1,000 m3/s.

Hydrographs. Left: Median annual volume by watershed. Right: Annual volume, 1964-94.