The removal of barriers, such as dams or weirs, is an increasingly common strategy for restoring river ecosystems. In Europe, these measures are core topic achieving the goal 25,000 kilometers of free-flowing rivers set by the recent rules and regulations nature restoration for 2030. However, public acceptance of these removals remains uneven, and civil service examination —often linked to cultural traditions, low environmental awareness, and misinformation—can influence or even hinder restoration efforts.

Social perceptions, cultural traditions, and attachment to the landscape

A few years ago, in a town in northern Navarre, the regional government convened a meeting experts and residents from the local villages. At that meeting ambitious project was presented project involved the demolition of several obsolete dams, with the aim of improving river connectivity and, specifically, facilitating the upstream migration of species such as salmon. During the explanation of the project milestones and actions, the name of a dam located in a nearby village was mentioned. It was then that a woman, as if spring-loaded, stood up and declared that that dam could not be demolished. She explained that the Virgin of the village was carried along the path that crossed over that dam during the May pilgrimage. That was reason enough to reconsider the demolition. Just as dams can only be demolished when they are no longer in use and their licence has expired, that dam had a cultural and intangible value that cannot be disregarded and that was not recorded in any official registry.

The Pros and Cons of Dams and Reservoirs

management remains a socially topic . Although the impacts on biodiversity are evident, it is also true that dams and their reservoirs provide significant benefits to society, such as renewable energy production, water supply, and the creation of areas for swimming and recreational fishing, in addition to cultural uses that are often only identified by listening to the community. At the same time, the effects on biodiversity can vary in intensity depending on their distribution and conservation status. Having knowledge precise knowledge about their status improve decision-making, especially regarding species of high recreational value, such as trout or Atlantic salmon.

Measuring the impact of dams

Traditionally, programs of study the impacts of dams have focused primarily on the number of kilometers of river that have been fragmented. But when we seek to prioritize the removal of obsolete dams, we should not only assess the length of the restored river sections, but also river biodiversity and its conservation. In this vein, indicators have been developed that consider the presence of fish populations as the primary “users” of rivers. But this is not enough: it is essential to incorporate public perception of dams, their impacts, and the ecosystem services they provide, in order to determine the cost-benefit ratio of restoring connectivity from all relevant perspectives. These perspectives must undoubtedly include the services these infrastructures provide us and the intangible values —such as those related to identity—that shape our perception of our environment. The latter have traditionally been the most difficult to address in management , which further highlights the need to promote effective communication and citizen participation in subject .

Social perception as a core topic the valuation of dams

In the project , which focuses on analyzing the ecological connectivity of dams in relation to the conservation status of fish, we have incorporated this social perspective into our evaluation the dams. We have focused on the Deva-Cares, Oria, and Bidasoa river basins due to the unique characteristics of the Cantabrian rivers and their populations. On the project website, we provide all the information regarding this evaluation . This preliminary information sample dams undoubtedly have a social value—in many cases, one tied to identity—that should not be overlooked.

Our findings underscore the importance of raising stakeholders’ awareness of the impacts of river barriers and the benefits of removing them when planning specific interventions. It is essential to involve local communities—particularly those most directly affected—to strengthen social acceptance of these actions and improve environmental governance. It is important to consider not only traditional ecosystem services but also intangible values, such as cultural assets or identity-based ties to the territory.

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Rafael Miranda researcher Biodiversity and Environment Institute and professor at the School of Science the University of Navarra. Ana Villarroya Researcher at Biodiversity and Environment Institute and professor at the School of Science the University of Navarra. 30.03.2026