STOCK NETTING WATER POLLUTION HYDROPOWER
AND FISH PASSAGE DECLINING WILD
What is the issue?
Hydropower can play a part in energy generation, albeit relatively small in England and Wales, provided that steps are taken to ensure schemes cause no adverse effects to our aquatic ecosystems, including to the hydro-geomorphology, in-stream substrate, fish, invertebrates, plants, and the flows required to support them, including fish migration.
The EA identified 26,000 potential hydropower sites in England and Wales, of which it was deemed 5,000 have a high probability of being developed. This would result in an average of 40 or so schemes being placed in each catchment. We have great concerns the cumulative impacts of multiple schemes within a catchment on fish migration, including salmon, sea trout, trout and the many coarse fish and invertebrate species which also need to move within a river system to complete their life cycles.
What S&TA has achieved so far
- Janina Gray represents S&TA on the EA's revision to the Good Practice Guidelines (GPG) Hydropower Technical and Steering Groups
- S&TA has agreed to support a project with the Game & Wildlife Conservation Trust (GWCT) to place pit tag readers into and around a hydropower scheme planned for the River Frome in Dorset, located about two miles upstream from the GWCT’s fisheries research facility at East Stoke. The idea of this project is to see which of three potential routes the smolts take at the hydropower site – through the Archimedes screw turbine, down the adjacent fish pass or via the hatches, and if the smolts suffer any delay to their migration as a result of the scheme. The pit tag readers will also be able to identify which route returning adults take on their upstream migration.
What still needs to be done?
- Hydropower must sit within integrated catchment management plans, coordinating all the issues relevant to river management, rather than being treated on a piecemeal basis as at present.
- Pre and post environmental monitoring should be required to gain information on all schemes where we do not already have sufficient information to show no/minimal impact on the surrounding ecosystem and associated species. At the moment we do not believe this information exists for any scheme designs, and therefore we seek an extensive programme of monitoring to reduce this uncertainty.
- All species fish passes should be in place at all hydropower schemes to ensure minimal impediment to natural up and downstream movements. All run-of-river hydropower schemes should include an exit / end of life strategy in the consent, whereby it is ensured that the river reaches and weir pools are returned to former condition in the event of cessation of operation for whatever reason.