| Sîrwan (Continues in Iraq as Diyala river) | |
|---|---|
 Sirwin River | |
 | |
| Location | |
| Country | Iran/Iraq |
| Physical characteristics | |
| Source | |
| • location | Western Iran |
| Mouth | |
• location | Tigris River |
| Length | 445 km (277 mi) |
| Basin size | 32,600 km2 (12,600 sq mi)[1] |
TheSirwan (Kurdish:Sîrwan,Sorani Kurdish:سيروان,Arabic:نهر ديالى,Persian:سیروان) is ariver and tributary of theTigris that originates in Iran. TheSirwan (or Sirvan) then runs mainly through easternIraq. It covers a total distance of 445 km (277 mi).
It rises nearHamadan, in theZagros Mountains of Iran. Descending through the mountains, for some 32 km it forms the Iran-Iraq border. It finally feeds into the Tigris belowBaghdad. Navigation of the upper reaches of the Diyala is not possible because of its narrowdefiles, but the river's valley provides an important trade route between Iran and Iraq.
The river is mentioned inHerodotus'Histories under the name Gyndes, where it is stated that the kingCyrus the Great dispersed it by digging 360 channels as punishment after a sacred white horse perished there. The river returned to its former proportions after the channels disappeared under the sand.TheBattle of Diyala River took place in 693 BC between the forces of the Assyrian empire and the Elamites of southern Iran.
Its origin in Kurdish and Persian is called "Sirwan", meaning 'roaring sea' or 'shouting river', as well as being the name of an ancient city near Ilam city in Iran. In theSassanid and early Islamic periods, the lower course of the river formed part of theNahrawan Canal. TheDiyala Governorate in Iraq is named after the river.
In Iran theDaryan Dam is currently under construction nearDaryan inKermanshah Province. The purpose of the dam is to divert a significant portion of the river to Southwestern Iran for irrigation through the 48 km (30 mi) long Nosoud Water Conveyance Tunnel and to producehydroelectric power.[2][3] In Iraq, the river first reaches theDarbandikhan Dam which generates hydroelectric power and stores water for irrigation. It then flows down to theHemrin Dam for similar purposes. In the lower Diyala Valley near Baghdad the river is controlled by theDiyala Weir which controls floods and irrigates the area northeast of Baghdad.
33°13′15″N44°30′23″E / 33.2208°N 44.5064°E /33.2208; 44.5064