Shadorvan of Ahvaz  

Shadorvan or same , old dam of Ahvaz was made near Polsiah on bottom pebbles of Karoun river and due to several waterways was renowned as Sedreh river (hundred roads) and water stored behind it via three gates irrigated lands and farms which placed on east and west of riverbank . in middle ages books Ahvaz shadorvan fame wasn’t less than Shoushtar shadorvan
And other olden buildings and according with Iranian stories its establishment returns to Kianian period . based on archeological studies at Sasanian period seven dams were made on
Karoun river , that last of them was Ahvaz dam . dam’s breakdown  time is exactly not known
But the dam probably ,demolished between second half of eleventh century and early twelfth century . in historical texts mentioned to its wheels which were used for irrigation and conducting water until tenth century . vestiges  of this big dam can be seen near railroad bridge
(Polsiah) .