Steffstep

Steffstep in Kollbrunn an der Töss

Steffstep is a fish ladder for use on small hydropower plants and other transverse structures that was developed by WRH Walter Reist Holding AG . The Steffstep fish ladder together with the Steffturbine and the Steffmaster form the so-called Steffworld.

functionality

As migratory organisms, fish are dependent on an intact network of rivers , but the reality is mostly different today. The functionality of the Steffstep corresponds to conventional slot passes. In contrast to these, the construction is based on an independent structure that is modular and can be attached to existing obstacles and easily removed again without major structural changes. The horizontal basins are separated from each other in a stepped manner, which means that only a relatively small amount of water is required. This makes the Steffstep particularly suitable for use on small to medium-sized rivers . The channel elements can be adapted to the respective fish fauna by means of different sizes . The individual basins are connected with ramps and filled with substrate, so that a migration of the organisms near the ground is possible.

field of use

The Steffstep is to be seen as a supplement to the previous solutions for restoring fish migration and, thanks to its space-saving modular system, expands the possibilities of river networking:

Obstacles not caused by power plants: In principle, renaturation with the removal of obstacles is the target state of the waters . However, it can take several decades in certain locations before this is achieved. A fish ladder can be used at these locations to bridge the time until the obstacle is removed. As soon as the necessary framework conditions have been created to remove the obstacle, the fish ladder can be removed again. A large part of the materials used can be reused at a new location. The Steffstep fish ladder serves as a temporary solution at these locations.
Power plant-related obstacles and problem locations: At small hydropower plants where fish migration must be ensured, external constraints (e.g. little space, floodplain protection areas, monument protection ) prevent the construction of conventional fish ladders. At these locations, the Steffstep fish ladder offers an alternative solution for fish migration. The Steffstep can also be used in residential areas, where conventional solutions are often unsuitable due to lack of space. The Steffstep can be used as a permanent solution at such locations.

Success control

The ecological functionality of a fish ladder is made up of its findability (can the fish find the entrance to the fish ladder?) And its passability (do the fish that have found the entrance also reach the top?). One of the greatest challenges of every fish ladder is the optimal positioning of the fish entrance and thus the ability to find the system. Each system must therefore be planned individually.

Brown trout in the Steffstep fish ladder

The ecological functionality of the Steffstep fish ladder was scientifically investigated by means of PIT tagging ( Passive Integrated Transponder ), trap counting and camera recordings between 2015 and 2016 in Kollbrunn an der Töss . The results show a high passability of brown trout through the facility, especially of adult animals. The investigation of further fish species is still pending.

Web links

"Steffstep" on a website of Walter Reist Holding AG

"Steffstep" on the company- related website fischwanderung.ch (with ill.) ( Memento from March 21, 2016 in the Internet Archive )

Individual evidence

^ WRH AG: Steffworld. (No longer available online.) Archived from the original on February 14, 2017 ; accessed on February 13, 2017 .
^ Eva Baier: Introduction to the fish migration. (No longer available online.) Fischwanderung.ch GmbH, archived from the original on February 14, 2017 ; accessed on February 13, 2017 .
^ Eva Baier: Steffstep fish ladder. (No longer available online.) Fischwanderung.ch GmbH, archived from the original on February 14, 2017 ; accessed on February 13, 2017 .
↑ Bunt, CM, Katapodis, C. & McKinley, RS: Attraction and Passage Efficiency of White Suckers and Smallmouth Brass by Two Denil Fishways. Ed .: North American Journal of Fisheries Management. No. 19 , 1999, p. 793-803 .
^ Bunt, CM, Castro-Santos, T. & Haro, A .: Performance of fish passage structures at upstream barriers to migrate. Ed .: River Research and Application. No. 28 , 2012, p. 457-478 .
↑ Eva Baier: Fish pass Steffstep - a solution for disconnected rivers? Potential application and efficiency of a new fish pass type. Master thesis. Ed .: ETH Zurich. 2016.
^ Eva Baier: Success control of the Steffstep fish ladder in Kollbrunn . Ed .: WRH AG. Hinwil 2016.

[1] WRH AG: Steffworld. (No longer available online.) Archived from the original on February 14, 2017 ; accessed on February 13, 2017 .

[2] Eva Baier: Introduction to the fish migration. (No longer available online.) Fischwanderung.ch GmbH, archived from the original on February 14, 2017 ; accessed on February 13, 2017 .

[3] Eva Baier: Steffstep fish ladder. (No longer available online.) Fischwanderung.ch GmbH, archived from the original on February 14, 2017 ; accessed on February 13, 2017 .

[4] Bunt, CM, Katapodis, C. & McKinley, RS: Attraction and Passage Efficiency of White Suckers and Smallmouth Brass by Two Denil Fishways. Ed .: North American Journal of Fisheries Management. No. 19 , 1999, p. 793-803 .

[5] Bunt, CM, Castro-Santos, T. & Haro, A .: Performance of fish passage structures at upstream barriers to migrate. Ed .: River Research and Application. No. 28 , 2012, p. 457-478 .

[6] Eva Baier: Fish pass Steffstep - a solution for disconnected rivers? Potential application and efficiency of a new fish pass type. Master thesis. Ed .: ETH Zurich. 2016.

[7] Eva Baier: Success control of the Steffstep fish ladder in Kollbrunn . Ed .: WRH AG. Hinwil 2016.