Removing tens of thousands of obsolete dams across Europe would boost wildlife populations and benefit communities, according to a new report. Only 40 per cent of Europe’s waterways are in good condition.
The density of dams, weirs and locks in Europe is far higher than previously suspected, with salmon, eel, sturgeon and other migratory fish encountering obstacles every kilometre of their journey on average.
These are the findings of the study ‘Dam Removal: A viable solution for the future of our European Rivers’. It estimated that in France, Spain, Poland and the UK, up to 30,000 mainly small dams are now obsolete.
“Dams have played a critical role in Europe’s development but they have also contributed to the slow death of our rivers and the catastrophic decline in freshwater species,” commented Stuart Orr, WWF Leader, Freshwater Practice, in a statement.
He added: “Tens of thousands of small dams and barriers are no longer in use but they are still in place: blocking fish migrations, stopping the flow of sediment and nutrients, and undermining the value of rivers to people and nature.”
While the defunct barriers provide no benefits to communities, they still prevent rivers from flowing freely, contributing to the disappearance of freshwater species, particularly migratory fish that can no longer reach their spawning grounds. This also affects birds that feed on fish as well as many other animals.
The report calls for governments across Europe to start removing these redundant dams to help breathe life back into river systems and provide new opportunities for local economies.
Results of dam removal have already proved successful. In the Netherlands, after two weirs were removed in 2015, the number of fish species in the newly connected stretches increased by an average of 30 per cent and the number of individual animals increased by 148 per cent.
Meanwhile, the removal of the Maisons-Rouges dam in France in 1999 has resulted in a spectacular surge in fish numbers with sea lamprey numbers soaring from barely any to over 41,000 within eight years, according to the statement.
“Freeing rivers offer additional advantages including cleaning water naturally, boosting tourism numbers and restoring a river’s natural flood defences, which is critical in the age of climate change,” concluded Orr.
Photo credit: Jacinta Iluch Valero/ CC BY-SA 2.0