First Deliverable of Workpackage (WP) 2. Within FIThydro, WP2 collects and analyses the available knowledge to assess the ecologic compatibility of hydropower plants (HPPs) based on case specific indicator species.


A lot of technologies exist to allow hydropower to be as fish-friendly as possible. FIThydro aims at identifying and improving these technologies, and creating new ones. This deliverable allows the identification of these technologies, distinguished in six topics: upstream and downstream migration, passage through turbines, influence of hydropeaking, implementation of the ecological-flow, as well as identification of fish characteristics and of their habitat related to hydromorphology. The aim is to identify and to fill the knowledge gaps for a comprehensive assessment of self-sustained fish populations affected by hydropower. Existing solutions, methods, tools and devices on a regional and overall scale have been identified. This will allow building a working basis of existing as well as innovative SMTDs including their application range.


This report constitutes a huge European state of the art collection on these topics. In the upstream and downstream migration survey, a detailed description of the most used fishpasses, the general design method and the data needed to implement a fishpass, the function range, water supply and positioning recommendations can be found. Downstream migration devices are also described and the procedure to implement them is explained. The turbine survey allows identifying the cause of fish damages due to turbines and comparing the different types of turbines. The fish survey explains fish migration behavior and behavior at barriers, swimming performance and physiology and population ecology. The hydromorphology part describes the different tools for velocity, sediment and habitat measurements. The hydropeaking survey states the legislation in the European states, the impact of hydropeaking on river as on fish and the related mitigation measures. The E-flow survey presents quickly the general steps to assess an E-flow, the legislation in each European country involved in the project and application at the test cases.

Baffle fishway at Trois Villes hydropower plant in France (picture: Pôle Ecohydraulique de l'AFB)

Fishway at the Guma hydropower plant in Spain (picture: GEA – Ecohidráulica)

Involved partners

The CNRS (Centre National de la Recherche Scientifique – National Office for Scientific Research) and the Pprime Institute in France are responsible for the  workpackage and for coordinating this work. The deliverable is a collaboration of different FIThydro partners, specifically:

  • Upstream and downstream fish migration SMTDs, responsible partner: CNRS – French Agency for Biodiversity
  • Turbines, responsible partner Voith
  • Hydropeaking, responsible partner IST
  • Ecological flow, responsible partner: CNRS – French Agency for Biodiversity
  • Hydromorphology, responsible partner: TUM
  • Fish characteristics, responsible partner: IGB

All this knowledge has been articulated in seven parts in a report. Additionally, to the above topics, the last part provides information on the specific Test Cases within the project.

It results in a report of 500 pages written by more than 15 authors and reviewed by all involved partners. This report will be useful because it represents one of the biggest European multi-topics state of art nowadays. It will be the basis of the second deliverable of Workpackage 2, consisting in the analysis of the present solutions and the potential solutions applied at the test cases and provide the limitation of the mitigation measures employed. The detailed Deliverable will be available next year.

The CNRS would like to thank all partners for their involvement in establishing this massive report.
For more information download the full report (29MB) or view all technical deliverables.

Author: Manon Dewitte, Laurent David (CNRS)