Page "Euphrates" Paragraph 5

The Euphrates receives most of its water in the form of rainfall and melting snow, resulting in peak volumes during the months April through May.

Discharge in these two months accounts for 36 percent of the total annual discharge of the Euphrates, or even 60 – 70 percent according to one source, while low runoff occurs in summer and autumn.

The average natural annual flow of the Euphrates has been determined from early-and mid-twentieth century records as at Keban, at Hīt and at Hindiya.

However, these averages mask the high inter-annual variability in discharge ; at Birecik, just above the Syro – Turkish border, annual discharges have been measured that ranged from a low volume of in 1961 to a high in 1963.