Europe has removed at least 239 river barriers across 17 countries in 2021. This is a 137% increase from the previous year. In total, 4,984 dams have been removed so far. According to the EU's 2030 Biodiversity Strategy, one of the key steps to improve degraded ecosystems is to restore 25,000 km of rivers to a “free-flowing state”. Dams, and other river barriers, lead to a loss of habitat for species belonging to riverine ecosystems. As per the World Fish Migration Foundation, 93% of migratory freshwater fish in Europe have declined. In some cases, the loss of income from fishing is larger than the value of the power produced by hydroelectric dams. All riverine barriers outlive their utility, and no longer serve any economic purpose. High sedimentation in older dams is a threat to their structural integrity and can lead to floods and other threats to life. A 2020 study found that around 15 per cent of the 1.2 million barriers on rivers and streams in Europe are obsolete. In most cases, costs of demolition are lower than costs of repair for such obsolete barriers. For the process to be successful, a river barrier must be removed through its full vertical extent. This is done to ensure that a significant portion of the stream can pass through for ecological flow and for fish to pass. Read more: https://www.thehindu.com/sci-tech/energy-and-environment/explained-the-2021-dam-removal-progress-report-and-why-removing-obsolete-river-barriers-is-important/article65420440.ece Thank you for watching our video! You can subscribe to our channel here: https://bit.ly/3c8Adi6 Visit https://www.thehindu.com/ for the latest updates, analysis, opinions, and more. You can also download our apps: Android: https://bit.ly/3nboBEi iOs: https://apple.co/3EDCwt4 The Hindu is committed to keeping you up-to-date with information on the developments in India and the world. We promise to deliver quality journalism that stays away from vested interest and political propaganda. You can support us by subscribing to our digital offerings here: https://bit.ly/3emywiz Follow us: Twitter: https://twitter.com/the_hindu Instagram: https://www.instagram.com/the_hindu/ #Europe #Dams #Rivers