Removing dams, weirs and culverts is hugely beneficial to river-dwelling species and the environment as a whole – but there may be risks in a densely populated, flood-prone country
Dotted along the length of Britain’s rivers are various obstacles – some as large as dams, others as small as weirs (which bisect a river like steps) – stopping creatures, sediment and plants from moving along the watercourse. Only 1% of the UK’s rivers are free of artificial barriers.
Moves are under way in many countries to remove such obstacles and let rivers “re-naturalise” and follow their own paths. But while many scientists agree that river barriers need to go in the UK too, other people are hesitant – concerned about creating unpredictable water flows in already flood-prone regions.