ĀBŠĪNA HAMADĀN RŪD, name of a drainage system that covers several streams and small rivers along the eastern flank of the Alvand Kūh; it flows north into the kavīr of Qom. The annual discharge of this river system varies between approx. 100 million cu m and 500 million cu m, depending on the amount of winter precipitation and the consequent snow melt. The annual peak of discharge is reached in March and April, but sometimes (e.g., 1968) as late as May or June. During this period the river reaches its maximum instantaneous flow, which may be as high as 90 cu m.
Since the waters of the drainage system are not salty, many villages use it for irrigation, both as surface and qanāt water. Because of this agricultural use and because of the lack of any considerable surface flow in summer, the river actually reaches the kavīr of Qom only after very wet winters.
Originally Published: December 15, 1983
Last Updated: July 19, 2011
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Vol. I, Fasc. 3, p. 247