More than 1 million barriers destroying Europe's rivers, new research shows

30 June 2020
by WWF -- last modified 30 June 2020

Europe's rivers are congested with more than 1 million barriers, new research has found.

The scale of river fragmentation recorded by the study is alarming, making Europe the most obstructed river landscape in the world. These barriers - such as dams, weirs, ramps, fords and culverts - have a terrible impact on rivers, affecting river health, the quality and availability of water, and threatening the survival of vulnerable species.

The Pan-European Atlas of In-Stream Barriers, produced by the EU Horizon 2020 project Adaptive Management of Barriers in European Rivers (AMBER), is the most comprehensive overview of river fragmentation in Europe to date. It contains information on 630,000 barriers. However, after walking 2,700 km of streams in 28 countries, AMBER researchers have found that more than one third of barriers are unrecorded, bringing the total in Europe to well over 1 million.

Carlos Garcia de Leaniz, AMBER project coordinator and Professor of Aquatic Biosciences at Swansea University remarks, "Even areas that were considered to be relatively pristine and well connected are in fact impacted by barriers. For example, in the Balkans, our field validation indicates that 80% of barriers do not appear in current inventories, making the fragmentation of these rivers much worse than people thought."

Traditionally, river managers have tended to view river fragmentation as being caused solely by large dams, but AMBER researchers have found this is seldom the case. In Europe, over 85% of barriers are weirs and other small structures. All barriers, whatever their size, impact on river health, changing a river's natural flow, blocking fish migration routes -- affecting fish stocks and the survival of vulnerable species -- and trapping sediments that protect riverbanks and deltas against floods and sea level rises. Many of the barriers mapped by AMBER are out of use, and could be removed as they break river connectivity and block the movement of sediments and organisms.

With hardly any free-flowing rivers left in Europe, the study adds to an already bleak picture. 60% of EU waters are currently not healthy, and freshwater species are amongst the most threatened in Europe - one in three European freshwater fish species threatened with extinction. Urgent action is needed to reconnect Europe's rivers.

In the EU, there is hope: The European Commission just last week opted to safeguard the EU's strong water legislation, the Water Framework Directive (WFD), with the EU's Commissioner for Environment, Ocean and Fisheries, Virginijus Sinkevicius, underscoring the need to boost implementation and enforcement. Last month, the Commission also put forward a concrete commitment to restore at least 25,000 km of free-flowing rivers in the EU Biodiversity Strategy.

The tools and commitments are there, but they are redundant unless fully implemented, enforced, and met with ambition and political will. EU Member States need to pull out all the stops to ensure the WFD works not just on paper but in practice, and to tackle the pressure of these barriers at the source. This should include drastically stepping up dam removals and barrier management in the next round of River Basin Management Plans (the plans Member States are required to submit under the WFD) for the period 2021-2027.

The data collected through the AMBER project starkly complements the first Europe-wide mapping of hydropower plants, released by WWF last year, which found Europe's rivers to be saturated with more than 20,000 hydropower dams, and more than 8,000 additional ones on the cards.

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