Wait a minute!
Upon looking at my maps more closely, I think I may be in error about the Bahmanshir River being definitely in Iran. the Bahmanshir is one of those "non-rivers" like the East River in New York. It has an outlet to the Persian Gulf that IS in Iran, but it also loops north back to the "Shatt al-Arab" (Euphrates River). So it IS possible that the point of capture the Iranians are describing is actually in Iraqi territory.
Still haven't found hide nor hair of the Arvand River, though.
--Boot Hill
Situated 115 kms south-west of Ahvaz, Iran on the Arvand Rood (Arvand River), Abadan is a leading economical centre in Iran. Rich mineral resources contribute to the importance of this major port. At night, the lights mirrored in the water of the river afford an impressive sight.
Walls riddled with bullet holes and bombed out buildings line the streets of Khorramshahr, Iran. It looks like a war zone, because, well, it was a war zone. Even though the war has been over for twelve years, this town has not been fully rebuilt or cleaned up. Along the Karun River, which divides the town in half, old, rusty shells of boats line the shore, and masts of sunken ships rise up from the water. A large bridge touches both shores, but is missing the middle section, the part that runs over the water.
The heat is oppressive, even though it's only April, which adds to the sense of hopelessness that this part of the city conveys. "This used to be a beautiful town," Hady tells us, as we survey the destruction before us. We drive near the mouth of the Karun River, where it lets out into the Arvand River, which leads to the sea.
"There." Hady points out across the Arvand in the distance. "That is Iraq."
_____________snip
"Saddam called the Karun River the Shatt-al-Arab, the 'Arab River,' in order to raise the support of the other Arab nations."
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