Eel and Fish Screening

Complying with the Eel Regulations – Our Self-cleaning Filters are Eel Friendly.

Eel screens and Eel screening may be required if you are pumping and screening raw water. You may be affected by the current Eel Regulations designed to help the recovery of populations of European Eels. The relevant legislation in the UK is ‘The Eels (England and Wales) Regulations 2009 Statutory Instrument No. 3344’, and ‘The EU Water Framework Directive – integrated river basin management for Europe‘.

The installation of low intake velocity eel screens ahead of pumping equipment may be a condition of your water abstraction licence in England and Wales.

In the USA the Environmental Protection Agency (EPA) has put in place measures to protect aquatic wildlife – in particular the measures outlined in the Clean Water Act Section 316(b).  These regulations are similar to the European Eel Regulations in that they stipulate intake velocities and mesh size sat water intakes.  The relevant US legislation is the EPA’s ‘CWA 316(b) Cooling Water Intake Structures‘.

What’s happening to the Eels?

Eel regulations - an eelThe regulations have come about due to a catastrophic decline in the eel population – succinctly described here in the Environment Agency Eel Manual Overview.

The regulations set criteria for the use of raw water and screening and pumping equipment. In simple terms, the regulations seek to ensure that Eels at all stages of life are protected.

The Eel regulations are concerned, in part therefore, with the intake velocity of pumps screens and strainers. For eel screening, the angle of approach, intake velocity and the size of mesh aperture are the determining factors.

Serendipitous Design

Eel friendkly filter complying with eel regulationsBy happy chance the design of Rotorflush self-cleaning suction intake filters lends itself to compliance with current Eel Regulations. Rotorflush self-cleaning suction intake filters make ideal eel screens ahead of pumping equipment when abstraction raw water.

Our filters operate by drawing a high volume of water through a large open area at low velocity, and backwashing debris wildlife etc. away from the mesh from inside the filter.

For most flow rates, our filters meet requirements for the protection of all eels, including elvers. The most stringent regulations set an intake velocity at the intake screen of mono more than 0.1 metres per second.  The intake speed for EPA 316(b) is slightly faster – 0.5 feet per second (0.15 metres a second)  – both well within the capability of Rotorflush self-cleaning intake screens. Find out more about  Rotorflush Eel screens HERE

Does this affect me?

The Eel Regulations affect all industry sectors abstracting, diverting or discharging into raw water, and may apply to you if:

  • you abstract more than 20 m3 in any 24 hour period
  • you have equipment (pumps, screens filters etc) that may obstruct Eels
  • or if you are installing or altering equipment that may obstruct Eels


Want to know more?

Pisces Conservation are an excellent Hampshire based specialist environmental consultancy with an impressive track record working within the power industry.


They have a website dedicated to understanding the current Eel Regulations.

Pisces also offer software and training, and are an invaluable environmental resource for industry.


What are the Eel Regulations?

A guide to the regulationsPisces Eel regulations logo


Do they affect me or my business?

Who is affected, who is exemptPiscesConservation1

glasseel1The Eel Regulations require companies in the UK and the EU who abstract and use raw water to ensure that their activity enables at least 40% eel “escapement”.  This is a requirement that came into force in 2015.

Ensuring that this figure is met may require specialist input by conservationists such as Pisces Conservation.

Companies can meet this and other requirements by implementing measures that reduce the harm to eels and elvers from pumping equipment and intake and outfall screens.

The Environment Agency (EA) has noted that Rotorflush filters can make an important contribution to Eel recovery, particularly for seasonal or temporary pumping applications   Section 4.5.1 of the EA “Screening at intakes and outfalls: measures to protect eel” says:

“Few manufacturers offer self-cleaning strainers that are appropriate to temporary works. One of the few available is the Rotorflush RF Series of self-cleaning inlet screens for surface-mounted pumps.”

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

Contact us for more information about how our products can help you abstract or move raw water without blocking strainers, pumps and other equipment while complying with current regulations.

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