Identification of migration corridors on nature-like unstructured block ramps by the holistic analysis of fish trajectories and flow conditions

Project Key Data


This project aims to identify and quantify migration corridors of ascending fish on nature-like unstructured block ramps by linking fish trajectories, ramp topography and local flow field. In cooperation with the project partners, combined biological and hydraulic investigations will be carried out on an existing block ramp in the river Ilme in Lower Saxony and on a 1:1 model of this ramp in the ‘Laxelerator’, a worldwide unique research facility for ethohydraulic experiments at the Vattenfall Hydraulic Engineering Laboratory in Älvkarleby (Sweden).

Since the quantification of the hydraulic conditions also describes turbulence patterns along the identified migration corridors and the areas avoided by fish during passage, the results contribute to the development of new and improved dimensioning criteria for nature-like unstructured block ramps and thus to the improvement of the ecological continuity of rivers as an essential prerequisite for achieving the objectives of the Water Framework Directive.

Concept of the project MigRamp

Work Packages

Staff Members

Prof. Dr.-Ing. Jochen Aberle (project leader)
Dipl.-Ing. Ralph Eikenberg (researcher)


  • Eikenberg, R., Andreasson, P., Aldvén, D., Persson, L., Aberle, J. (2022). "Construction of a full-scale physical model of an unstructured block ramp", Proc. 39th IAHR World Congress, June 19-24, 2022, Granada, Spain, Ed. Miguel Ortega-Sánchez, International Association for Hydro-Environment Engineering and Research - IAHR, pp. 1361-1370, doi://10.3850/IAHR-39WC2521716X2022838.
  • Eikenberg, R. & Aberle, J. (2022). "MigRamp - Nachweis von Wanderkorridoren auf naturnahen unstrukturierten Sohlengleiten", Beitrag zum 45. Dresdner Wasserbaukolloquium 2022. In: Dresdner Wasserbauliche Mitteilungen, Heft 68, 115-124. Online: https://hdl.handle.net/20.500.11970/108916.
  • Eikenberg, R. & Aberle, J. (2021). " In-situ survey of an unstructured block ramp." Book of Extended Abstracts: Webinar on Experimental Methods and Laboratory Instrumentation in Hydraulics, 13-15 April 2021. Geophysical Data Bases, Processing and Instrumentation, vol. 434 (E-11), 2021, pp. 63-65, doi:10.25171/InstGeoph_PAS_Publs-2021-020.
Sponsored by Deutsche Bundesstiftung Umwelt (DBU)