Identifying key operational stages of the HPP reservoir through sediment transportJavornik, Luka (Avtor) Mikoš, Matjaž (Avtor) Kryžanowski, Andrej (Avtor) sediment transportreservoir operation stagesediment erosionsediment depositionreservoir sedimentationsediment managementRun-of-river dams significantly disrupt sediment balance, so managing them accordingly isessential. To address this, we analysed the spatial-longitudinal and temporal distribution ofboth erosion and deposition of sediments by applying a sediment transport model tohydrological events of 2010, 2014, and 2023 on the Vrhovo-Boštanj HPP reservoir chain onthe Lower Sava River in Slovenia. We aimed to identify the stages of sediment transport thatoccur during high and extreme hydrological events and their influence on HPP operation.Results show discharge patterns, valid for the Lower Sava River HPP chain. Incipient motionin the silts and fine sands prevailing in the reservoir mostly starts in the range of 0.7×Q1,which also marks the onset of erosion processes in less damming-affected reservoir sections;in other sections, depositional processes dominate. Deposition in dam-affected areas startswhen discharges decrease to 1.3×Q1 on average. These thresholds result from dammanagement, flaps, and gates operation by operational rule curve. Identifying dischargestages through a set methodology is key to modifying the dam operation at sedimenttransport-inducing discharges. Application of this methodology follows, focusing on settingup the operational rule curve by including sediment transport boundary conditions whileconsidering other users of the present ecosystem.20252025-12-10 13:52:01Članek v reviji176728sl