Sediment transport processes in Alpine rivers are of great relevance due to their ecological, energetic and risk-related consequences. Sediment fluxes provide the hydromorphological conditions supporting dynamic aquatic ecosystems. To achieve these conditions, sediment continuity must be maintained or enhanced if already disrupted. Such goal is often in conflict with: (i) flood risk mitigation, as sediment transport may strongly amplify flood hazards; and (ii) hydropower production, as the required hydraulic structures cause alterations of longitudinal sediment transfer and of its temporal dynamics. Therefore, decision makers involved in river basin management in the Alps – and thus in South Tyrol as well – are facing the urgency to test policies able to reconcile these conflicting targets, especially in river basins hosting numerous hydropower and flood-mitigation structures.

Aims and Activities

The main goal of the integrated project SEDIPLAN (research and innovation parts) is to investigate and to quantify sediment transport and morphological trajectories of river channels within the territory of the Autonomous Province of Bozen-Bolzano (APB) at three different spatial and temporal scales (small, intermediate and large), with the final aim to identify priorities for sediment management. In particular, SEDIPLAN-r is an innovative project funded by EFRE-FESR (521,600 euro) which aim at:

  1. estimating annual sediment yields in the main channel network of APB through an evidence-based approach, which integrates data from ad-hoc monitoring stations, hydropower reservoirs and sediment retention basins;
  2. encompassing an array of different spatial and temporal scales relevant for sediment management, from the short and localized flood scale to the centennial, Province-wide channel variations (observed and expected);
  3. promoting an active collaboration with three important hydropower companies;
  4. integrating a scientific project with an innovation project led by private companies (see companion project “SEDIPLAN-i).

Expected Results

  1. Map of estimated medium-term annual sediment yields at the Province scale, based on multivariate analysis (cluster analysis) on sedimentation data (Milestone 3.1);
  2. Relationships between past channel variations (width, planform), time and controlling factors (past evolutionary trajectories, Milestone 4.1), and map of the expected “sensitive-to-change” reaches for the next future (Milestone 7.1);
  3. Equations describing the statistical relationships between bedload rates and geophone signal at the different monitoring stations (Milestone 5.1 and 5.2), and between sediment transport rates/volumes (suspended and bedload) and flow discharge/volume, differentiated based on season and runoff origin (Milestone 5.3 and 5.4);
  4. 3D numerical model to investigate sediment transport at hydropower structures (Milestone 6.1), and guidelines for management strategies related to hydropower sediment (Milestone 8.1)
  5. Event-related sediment budget composition by morphological monitoring, applied to flood and debris flows which will occur during the project (Milestone 9.1)
  6. List of priorities for sediment management plan in South Tyrol (Milestone 10.1)