Eel and Fish Screening

How Do Rotorflush Intakes Work for Eel Screening and Fish Protection?

Rotorflush screens are designed for low intake speed through the screen mesh ; in addition, they are self-cleaning, so there is always a backwash from inside the screen to clear debris and wildlife off the mesh. 

The design of our self-cleaning filters and intake gives them a low intake velocity and a high open area, enabling compliance with current Eel regulations when pumping and abstracting raw water.  

For any given flow rate being drawn or pumped, the intake velocity through the screen will decrease if the screen area is increased. Currently, the typical intake velocity of eel screens for the protection of glass eels and elvers is 0.1 metres / second, although this is likely to decrease as more stringent environmental regulations come into force. 

As well as a low intake speed, the Eel regulations only allow a maximum screen aperture of 2 mm.  2 mm mesh can block very quickly, and this is a challenge for most equipment. Unlike most other self-cleaning filters and screens that only clean after the mesh has begun to block, Rotorflush intakes are designed to prevent blinding in the first place. They have a continuous self-cleaning backwash that keeps the mesh clear as water is drawn though the mesh. 

Self-cleaning Suction Intake Screens

Rotorflush Self-cleaning Eel Screens and Eel Screening Intake Strainers are designed for use on the suction hose of surface mounted pumps. They can also be used for gravity fed intakes, as long as a pump is used to supply the backwash. 

The screens can be mounted vertically or horizontally and Rotorflush offer guide rail systems for lifting and maintenance.

These screens are typically used for large volume intake and comply with Eel regulations and EPA Rule 316(b). The 2 mm mesh and low intake velocity protects elvers and eels, and the self-cleaning mechanism ensures that the mesh stays clear.

Submersible Pumps with Self-cleaning Suction Intakes

Rotorflush also manufacture and supply submersible Filterpumps™.  These are submersible centrifugal multistage pumps with built-in self-cleaning intakes. This means they can be fitted with small intake screen mesh sizes and can comply with Eel regulations.

Screening and pumping are combined in the water source, eels and fish are screened, and the mesh stays clear because it continuously back washes as water is pumped.