EDITOR’S NOTE: Call to Earth is a NCS editorial sequence dedicated to reporting on the environmental challenges dealing with our planet, along with the options. Rolex’s Perpetual Planet Initiative has partnered with NCS to drive consciousness and schooling round key sustainability points and to encourage constructive motion.
The river arrived virtually instantly.
As the dams on the Hiitolanjoki in Finland got here down, it started to alter — the water quickened and cooled, sounding much less like a reservoir and extra like a river once more. Then got here the fish.
For the primary time in additional than a century, salmon pushed upstream previous the place three hydropower dams as soon as stood, reclaiming a stretch of water that had been reduce off for greater than a century.
Similar transformations are unfolding throughout Europe, the place countries are dismantling ageing dams and weirs — boundaries that when powered mills and factories however now typically serve little function.
“Once you take a barrier out, the river takes over,” Angela Ortigara, senior adviser and freshwater strategist at WWF Netherlands, informed NCS. “It’s one action that has an immediate effect and a long-term benefit.”
A file 603 boundaries had been eliminated throughout 21 countries in 2025 — the very best quantity ever recorded — in response to the newest annual report by Dam Removal Europe, a coalition of six organizations working to revive river connectivity.
The removals helped reconnect greater than 3,740 kilometers (2,324 miles) of rivers throughout the continent and are tied to the EU’s purpose of restoring 25,000 kilometers (15,534 miles) of free-flowing rivers by 2030.
According to the report, launched final week, the quantity of eliminated boundaries surpassed the earlier file set in 2024 by 11%.
Removals in 2025 had been additionally six occasions larger than the primary rely carried out in 2020.
The numbers sign that river restoration is changing into extra extensively adopted but in addition mirror a broader reassessment of how rivers perform in an period of local weather extremes. What was as soon as seen as progress is more and more considered as a rising environmental legal responsibility.
An estimated 1.2 million boundaries — together with dams, weirs, culverts and sluices — fragment Europe’s rivers, in response to the Adaptive Management of Barriers in European Rivers (AMBER) analysis undertaking, one of essentially the most complete assessments of river connectivity ever carried out on the continent. Many of the constructions had been constructed a long time in the past for hydropower, navigation or agriculture, however hundreds are now out of date.
Scientists and environmental teams say the results will be far-reaching.
“When a river is dammed, its channel — once protected by riparian vegetation — is transformed into a pond or reservoir of still water exposed to the sun. This significantly increases water temperature,” stated Pao Fernández-Garrido, senior grants supervisor for the European Open Rivers Programme, a Europe-wide funding initiative that helps the removing of small dams and river boundaries to revive pure river ecosystems.
Large volumes of water in reservoirs will also be misplaced via evaporation. Organic materials trapped in reservoirs accumulates and decomposes over time, releasing methane — a potent greenhouse gasoline that considerably contributes to international warming, Fernández-Garrido informed NCS.
Fragmented ecosystems are additionally far much less ready to deal with rising floods, droughts and local weather extremes, in response to the European Environment Agency. Over the previous decade, 9 out of 10 pure disasters on the continent had been water-related, it stated.
“We have lost around 80% of our wetlands over the last millennium through drainage, sealing and degradation,” the company informed NCS. “Wetlands help reduce these risks by acting like natural sponges, absorbing water during floods and releasing it slowly during droughts.”
Dam Removal Europe stated river fragmentation is a serious contributor to the decline of freshwater biodiversity in Europe, citing a current European Commission evaluation that discovered greater than 42% of the continent’s freshwater fish species are threatened, whereas practically two-thirds are thought of in danger of changing into threatened or are already near that standing.
Species reminiscent of Atlantic salmon and European eel, together with some trout populations, will be blocked or delayed from reaching upstream habitats required for replica, contributing to inhabitants declines, or, in some circumstances, native extinction.
Even the place fish passes are put in, their effectiveness varies, they usually typically fail to accommodate weaker-swimming species, leaving vital stretches of river ecosystems partially disconnected.
The impression extends past fish. River connectivity helps complete aquatic ecosystems, from bugs to birds and mammals. When sediment circulate is disrupted, riverbeds will be simplified and fewer appropriate for spawning, whereas altered temperatures and circulate scale back habitat range.
There are rising considerations, too, about Europe’s ageing water infrastructure. Many out of date boundaries are not correctly maintained and may grow to be security dangers as they deteriorate, notably throughout excessive climate occasions.
“Building river barriers brings a long list of safety and environmental problems,” stated Fernández-Garrido. “It is always safer and more cost-effective to work with nature rather than against it.”
The rising momentum behind river restoration is now additionally being strengthened via the EU nature restoration coverage.
However, the coverage has additionally confronted criticism from some farming teams and policymakers involved about potential impacts on land use and rural livelihoods.
The EU’s Nature Restoration Regulation, which entered into pressure in 2024, units binding targets to revive at the least 20% of the EU’s land and sea areas by 2030, together with restoring at the least 25,000 km of rivers to a free-flowing state. It goals to revive practically all ecosystems in want of restoration by 2050. The laws marks the primary time river connectivity and barrier removing have been embedded in EU legislation.
“This regulation has the potential to be a real game changer. It is not just about protecting what is left. It is about bringing nature back, about bringing our rivers back,” the European Environment Agency stated.
Removing a dam, nonetheless, isn’t so simple as tearing down concrete.
Projects can take years of environmental assessments, engineering research and negotiations with dam house owners and native authorities. Sediment should be rigorously managed, riverbanks stabilized and ecosystems monitored after demolition.
But as soon as boundaries are eliminated, the transformation can occur remarkably quick.
In Finland, the removing of the three hydropower dams alongside the Hiitolanjoki River between 2021 and 2023 reopened migration routes for critically endangered landlocked salmon, restoring entry to spawning grounds that had been blocked because the early 1900s. Salmon returned to elements of the river inside the first migration season.
Farther east, consideration is now turning to the Palokki hydropower dam in Finland’s Vuoksi river basin, the place plans are underway to revive connectivity throughout one other closely fragmented watershed.
“When this project is implemented, it will be the biggest Open Rivers Program project ever supported,” Fernández-Garrido stated. “This dam removal will open 1,523 kilometers (946 miles) of river.”
Elsewhere throughout Europe, comparable restoration efforts are accelerating.
In France, the removing of the Vezins in 2020 and La Roche-Qui-Boit in 2022 dams on the Sélune River, which had been working because the Twenties and Thirties, restored practically 90 kilometers (56 miles) of free-flowing river in a single of the most important dam removing tasks ever undertaken in Europe.
In England’s Lake District, the dismantling of Bowston Weir in 2022 on the River Kent has helped restore extra pure river circulate, enhancing situations for migratory fish and surrounding ecosystems.
In Belgium, culvert removals within the Anlier forest are reconnecting smaller tributaries that play an necessary position in native biodiversity.
Spain, Denmark, Sweden, Germany and Estonia have all undertaken barrier removing tasks lately, although the dimensions of these efforts varies significantly between countries.
In 2025, Sweden eliminated essentially the most boundaries, 173, adopted by Finland, 143, and Spain, 109.
Countries in southern and southeastern Europe, together with Slovakia, Croatia, Bosnia and Herzegovina, Greece and even war-torn Ukraine, have additionally undertaken barrier removals lately, Ortigara identified.
In the United States, giant dam removals have proven how shortly rivers can get better as soon as boundaries come down.
On California’s Klamath River, the most important dam removing undertaking in US historical past was accomplished in 2024, reopening hundreds of miles of habitat for migratory fish. On Washington’s Elwha River, earlier dam removals restored sediment circulate and triggered the return of fish and vegetation after greater than a century of disruption. In Europe, many removals nonetheless contain a lot smaller constructions — low weirs, culverts and ageing hydropower boundaries — however specialists say their cumulative impression is rising.
“We have more than a million barriers in Europe,” Ortigara stated. “Removing a few hundred each year is a start — but it’s not enough.”
Success, specialists say, will rely upon restoring complete river stretches and drainage basins, working intently with native communities and making certain that when connectivity is restored, it’s maintained over time. “The real challenge now is implementation — doing it at scale and in a strategic way,” the European Environment Agency stated.
“When a river is alive, it has a sound,” Ortigara stated. “You hear it trickling down the rocks. You see vegetation around it. It is this flow of life.”
Across Europe, that sound is now starting to return.