Fish Ahoy with ecological fish migration

We at Hydroconnect take the concerns and questions of fishermen and environmental protectionists seriously. Therefore, we welcome an active dialogue in the interest of an environmentally friendly, sustainable solution for humanity, energy and the environment.

Why fish ladders?

Fische wandern ähnlich wie Zugvögel. Diese Fischwanderung ist nötig, um die passenden Nahrungsplätze und die richtigen Bedingungen zur Fortpflanzung vorzufinden. Der Bau von Wasserkraftwerken und das Fehlen von bidirektionalen Fischwanderhilfen führten über die vergangenen Jahrzehnte hinweg zu einem Stückwerk der europäischen Flusslandschaft. Damit wurde eine weitläufige Fischwanderung verhindert, Fische in ihrem Lebensraum beschränkt und das ökologische Gleichgewicht nur spärlich aufrecht erhalten.

Fish migrate similar to migratory birds. Their migration is necessary to reach suitable sources of food and the right conditions for procreation. The construction of hydroelectric power plants and the lacking of bidirectional fish migration facilities lead to a strong segmentation of the european river landscape over the last decades. This lead to a strong restriction of the fish habitat and endangered the ecological balance.


The EU-Guidelines for the fish migration 

These guidelines state the need to make full fish migration possible in rivers and streams, therefore requiring also the passing of transverse structures.
This became hydroconnects mission: The Electricity generating fish bypass by Hydroconnect allows bidirectional fish mirgration, meaning fish ascent and descent - suitable for fish of diverse species, sizes and ages.
Therefore the innovative fish ladders of Hydroconnect already tody meet the legal requirements of the upcoming EU guidelines.


Power generation and fish migration combined
At the same time based  on a hydropower screw  the electricity generating fish bypass by Hydroconnect also generates green energy, making this solution for fish migration also a profitable investment.


Questions and answers concerning fish migration and environment

Additional Questions

Hydro-Connect GmbH
 +43(0) 720 720 900-850
 office@hydroconnect.at

Each location is planned separately, and the machine size is defined according to financial and ecological criteria. Drum diameters of up to four metres are possible. Hence, this system provides up to ca. 2 metres of space (in both directions) for the predominant fish species. The screw diameter is oriented in any case around the predominant fish in the waters in order to comply with the EU Water Framework Directive (WFD 2000/60/EC).
Yes, of course. All research programmes and monitoring studies were accompanied by the Institute for Hydrobiology and Water Management (HG) at the University of Natural Resources in Vienna (BOKU). 100% freedom from injury was confirmed by BOKU in numerous studies.
Through an additional EU patent, the specially shaped double screw in the fish entry, the adapted speed of the system as well as the shape of the shell as a gap-free drum guarantee that the hydrodynamic screw with double rotating cylinders will provide 100% freedom from injury for all water life. This was confirmed by studies conducted by the University of Natural Resources in Vienna (BOKU).
No. The lower screw area is designed and patented so that it creates a luring current for fish and water life. That way the fish find the way via the fish ladder without being forced to do so.
There is a current leading to the screw in the bottom area of the entry, which is very well suited for fish and pentos that are weakened from swimming. (Also see Siehe auch Technologie)
Each individual fish is released into a calm zone close to the bank by means of a “fish discharge chute” (discharge of the ascended fish with a marginal slope) over the dam, protection and coarse screen. The fish continue their migration after an orientation phase.
No. It is now possible for fish to pass transverse structures voluntarily, stress-free and injury-free and to move effortlessly upstream or downstream. The natural ecological balance ensures that the fish population remains constant or rather that the populations recover again if fish can reach their spawning grounds, winter habitats and other important habitats at any time. Therefore the river life is once again autonomous and hence the biodiversity is promoted.
Even in floods, fish are not simply swept away, rather the population normalises again after a short amount of time. Fish that are swept away in a flood can return to their original locations at any time. That way the population can recover again quickly.
More than 4000 hydropower plants in Austria’s rivers have no, or non-functioning fish bypasses. Altogether, according to the ministry, there are 33,000 migration obstacles in Austria alone due to transverse structures. They must be made passable in accordance with the EU Water Framework Directive in the interest of providing environmental protection for fish. Some of these locations have energy production potential, which can be converted into valuable electricity with the HYDROCONNECT system.
No, the hydrodynamic screw with double rotating cylinders is for the passage of the strongest and weakest swimming species of fish at all stages of life. For more details, go to “ Studien.