This fact sheet examines the functional elements of a fish protection system and explains when a rake is a fish protection rake. The fact sheet "Wann ist ein Rechen ein Fischschutzrechen? (When is a rake a fish protection rake?)" is available for download.

The key messages of Fact Sheet No. 05 are:

• It is mandatory that a fish protection system at both new and existing hydropower facilities perform three functions: Blocking, guiding, and diverting.
• In fish protection systems, fish screens and bypasses form a functional unit. Screens without bypasses or bypasses without suitable screens do not constitute a protection system.
• Horizontally inclined fish protection screens guide fish across the entire water column to the bypass. The fish can remain in their natural swimming horizon.
• Vertically angled fish screens can direct fish to bypass entrances or collection devices near the surface across the entire width of the turbine inlet.