Fish pass options and structure passability

Weirs, dams, sluices, gauging stations and other barriers to fish movement are commonplace on our rivers and waterways.

Designing effective fish passes and passage options at these barriers requires detailed fisheries, engineering and hydrology knowledge, with the benefits of proposed improvements carefully balanced against the need to manage existing water resources as well as flood monitoring and forecasting.

APEM’s experienced team has carried out numerous options appraisals and designs for fish passes at standalone sites and for larger projects such as flood defence improvements and hydropower schemes. We have produced or overseen engineering and construction designs, both outline and detailed, for approval by the Environment Agency’s National Fish Pass Panel.

Our fisheries team has also assessed the passability of hundreds of barriers using state-of-the-art assessment techniques such as WFD111 and hydraulic modelling.

Our work is guided by the Environment Agency’s Fish Pass Manual.

Eel pass ready to be installed at a weir.

Eel pass ready to be installed

APEM has undertaken numerous projects to assess fish barriers and fish passage options across whole river catchments throughout the UK. We identify potential barriers and provide guidance to prioritise actions at a catchment level.

This allows clients to develop the most cost-effective measures and optimise benefits in line with environmental legislation, such as the Water Framework Directive and Eels Regulations.

Site by site approach

Fish Passes and BarriersA weir before removal

No two sites are the same and the unique features of different sites affect the way that fish can navigate them. Many passage improvements must therefore be bespoke and our team is experienced in undertaking fish pass and passage assessments and providing solutions for a wide range of sites, including:

  • Gauging stations
  • Hydropower schemes
  • Sluices
  • Pumping stations
  • Culverts
  • Bridge footings
  • Tidal flaps
  • Reservoirs
  • Navigation locks.

Fish pass solutions and monitoring

Our experience allows us to identify cost-effective fish passage solutions at complex and challenging sites. The result is an unrivalled track record of providing solutions at locations such as tidal environments, ecologically sensitive sites, flood risk zones and remote locations.

APEM’s team of experts also carries out monitoring to determine the passability of structures and the effectiveness of fish passes. We design and implement bespoke monitoring programmes, including tagging and tracking studies, to assess the efficiency and performance of fish passage solutions.

If you have any queries, please contact Paul Gratton, principal fisheries scientist.
Alternatively you can email us here. Or call 0161 442 8938.