▁Era , ▁which ▁began ▁after ▁the ▁occupation ▁of ▁Iran ▁by ▁Alexander , ▁it ▁seems ▁that ▁the ▁q an ats ▁were ▁abandoned . ▁ ▁In ▁terms ▁of ▁the ▁situation ▁of ▁q an ats ▁during ▁this ▁era , ▁some ▁historical ▁records ▁have ▁been ▁found . ▁In ▁a ▁study ▁by ▁Russian ▁orient al ist ▁sch ol ars ▁it ▁has ▁been ▁mentioned ▁that : ▁the ▁Pers ians ▁used ▁the ▁side ▁branches ▁of ▁rivers , ▁mountain ▁spr ings , ▁well s ▁and ▁q an ats ▁to ▁supply ▁water . ▁The ▁sub ter rane an ▁gall eries ▁exc av ated ▁to ▁obtain ▁ground water ▁were ▁named ▁as ▁q an at . ▁These ▁gall eries ▁were ▁linked ▁to ▁the ▁surface ▁through ▁some ▁vertical ▁sh aft s ▁which ▁were ▁s unk ▁in ▁order ▁to ▁get ▁access ▁to ▁the ▁gallery ▁to ▁repair ▁it ▁if ▁necessary . ▁ ▁According ▁to ▁the ▁historical ▁records , ▁the ▁Par th ian ▁k ings ▁did ▁not ▁care ▁about ▁the ▁q an ats ▁the ▁way ▁the ▁A cha emen id ▁k ings ▁and ▁even ▁S ass an id ▁k ings ▁did . ▁As ▁an ▁instance , ▁Ar s ac ▁III , ▁one ▁of ▁the ▁Par th ian ▁k ings , ▁destroyed ▁some ▁q an ats ▁in ▁order ▁to ▁make ▁it ▁difficult ▁for ▁Sele uc id ▁Ant io chus ▁to ▁advance ▁further ▁while ▁fighting ▁him . ▁The ▁historical ▁records ▁from ▁this ▁time ▁indicate ▁a ▁perfect ▁reg ulation ▁on ▁both ▁water ▁distribution ▁and ▁far ml ands . ▁All ▁the ▁water ▁rights ▁were ▁recorded ▁in ▁a ▁special ▁document ▁which ▁was ▁referred