Seven challenges to implementing the EU Nature Restoration Law on river ecosystems identified by researchers

With the upcoming adoption of the EU Nature Restoration Law (NRL), a new agenda for European biodiversity is to be undertaken. Through establishing binding targets, the regulation is set to require that countries achieve restoring and protecting at least 20% of EU land and sea by 2030, and restoring all degraded ecosystems by 2050. The EU NRL sets specific goals for reversal of pollinator decline, increasing farmland bird populations, increasing forest biodiversity, restoring marine habitats, expanding urban green spaces, and restoring free-flowing rivers.

The NRL aims to restore 25,000 km of free-flowing rivers by 2030. While this regulation represents an important opportunity for countries in the EU to boost the restoration of European rivers and for achieving the goals set in the EU Biodiversity Strategy, there is still an ongoing need for concerted efforts to achieve efficient evidence-based policies.

In a recent scientific study by a team of European researchers led by the BioAgora partner institution Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) in Berlin and the University of Natural Resources and Life Sciences (BOKU) in Vienna, seven potential challenges to the future implementation of the NRL in river restoration are identified, and recommendations on the overcoming of these challenges are made.

The study, titled “Reviving Europe’s rivers: Seven challenges in the implementation of the Nature Restoration Law to restore free-flowing rivers”, showcases some ambiguities in the proposed EU NRL. The study elaborates on the potential consequences of leaving these aspects open to interpretation, and also suggests potential solutions to be applied in the regulation’s provisions and subsequent application, thereby ensuring efficient river biodiversity restoration.

“First of all, it is important to underline that the NRL is an absolutely needed step in the right direction, also clearly confirmed from a scientific point of view. But river ecosystems are complex networks and their connectivity plays an important role. Hence, clear definitions of the central terms in the law are crucial for enabling efficient implementation,” explained IGB researcher Dr. Twan Stoffers, lead author of the study and a member of the BioAgora research team on the freshwater demonstration case.

Prof. Sonja Jähnig, co-senior author and scientist at IGB, adds to this: “Restoring an additional 25,000 km of free-flowing rivers by 2030 will not suffice to halt the decline of freshwater biodiversity, let alone reverse it. Due to the relatively small number of rivers to be restored, the implementation should focus on areas where restoration efforts will result in the most substantial improvements to ecological conditions, freshwater resources, and ecosystem services. In fact, it makes little sense to prioritise restoring degraded systems while still degrading near-natural or pristine systems at the same time”.

The seven potential challenges to the implementation of the NRL in relation to free-flowing river restoration are outlined by the research team as follows:

Challenge 1: Develop a clear definition of free-flowing rivers, barriers, and reference areas

Clear legal definitions are key for the successful implementation of regulations. With the advancement of the definitions on restoration of river connectivity by the European commission, authors of the study provide recommendations on further improving the definition of free-flowing rivers, barriers, and reference areas. Using a scientifically derived holistic approach, the authors define free-flowing rivers as fluvial systems in which ecosystem functions and services are unaffected by any human-induced change in fluvial connectivity.

Challenge 2: Consider the network structure of rivers and their connectivity dimensions

A river is more than just its visible surface; it’s complex in its structure, connectivity, and interaction with its environment. Firstly, rivers are connected in three ways: longitudinal (upstream and downstream), lateral (e.g., with floodplains, other backwaters, and small streams), and vertically (groundwater, and the atmosphere). Secondly, these connections change with the river’s dynamic behavior, which can expand or shrink the space it occupies depending on changes in river discharge and flow, and is regarded as the fourth dimension of rivers (temporal connectivity).

Although useful, this 4-dimensionality model falls short of adequately representing the longitudinal dimension: rivers are not linear landscape features that simply grow in size from a source to the ocean, but rather form spatially explicit, hierarchically organised, dendritic networks that integrate a landscape. The authors realize that this potentially adds more complexity to the implementation planning, but stress its importance for the efficiency of the planned restoration activities. This network perspective needs to be considered when designing efficient protection of their biodiversity and functioning, and that is why the authors also suggest including minimum river section length as a restoration target for free-flowing rivers.

Challenge 3: Incorporate meta-ecosystem thinking in restoration planning

Authors also outline the importance of considering the connectivity within and among aquatic systems, as well as their riparian and terrestrial environments. To fully integrate the ecological dimension of free-flowing rivers, restoration efforts must encompass interconnectedness and interactions within and among aquatic systems. The authors of the study emphasize that meta-ecosystem thinking, which considers interconnectedness within riverscapes, should guide European river restoration efforts, fostering collaboration at landscape and catchment scales. For optimal results, this approach should also foster active transboundary collaboration and the creation of such restoration plans that recognize the transboundary nature of river ecosystems and biodiversity restoration.

The seven challenges to restore free-flowing rivers. Graphical abstract of the research article Stoffers et al. (2024). Reviving Europe’s rivers: Seven challenges in the implementation of the Nature Restoration Law to restore free-flowing rivers. WIREs Water, e1717.

Challenge 4: Prioritise actions to maximise quantity and quality of free-flowing river networks

The NRL regulation’s focus on the restoration of an additional 25,000 km of free-flowing rivers by 2030, relies on a variety of restoration goals such as initiating hydromorphic dynamics in floodplains, and removing obsolete barriers in free-flowing rivers. However, the actions in this direction may not be sufficient to effectively halt the decline of freshwater biodiversity. To overcome this challenge, researchers propose that restoration efforts are optimized, and priority to be given to areas where restoration, including barrier removal, can lead to substantial improvements in ecological conditions, freshwater resources, and ecosystem services. The proposed prioritization approach considers not only physical location and economic factors but also expected ecological outcomes, ensuring the most effective allocation of resources for achieving the biodiversity objectives.

Challenge 5: Enhance awareness, stakeholder participation and citizen engagement

Still, rivers are often predominantly seen as resources for specific economic interests such as extractive industries, agriculture, and infrastructure development. Additionally, freshwater processes are often hidden from the human eye and not recognised as integral parts of nature, leading to a lack of awareness among stakeholders and citizens that the biodiversity and integrity of freshwater systems is the basis for the ecosystem services they provide to people. It is important to engage with stakeholders for understanding the specific human demands relevant for each river network and therefore for successful river restoration. The authors recommend the full inclusion of all stakeholders in conservation and restoration efforts: policymakers, authorities, river managers, protection and user associations, and the general public.

Challenge 6: Consider conflict areas with other legislative frameworks

Resolving conflicts and finding territorial compromises at the riverscape level is critical for effective water management and aquatic biodiversity protection. But still, conservation and restoration efforts are often not given the same priority as competing interests, such as agricultural production or hydropower generation. The Common Agricultural Policy (CAP) or the Renewable Energy Directive (RED) and also the EU’s regional infrastructure instruments such as the Cohesion Fund are conflicting with restoration goals. In general, nature conservation needs are considered to a moderate extent, whereas sectoral demands — often justified as “societal demands” – tend to be prime considerations, the scientists argue. These conflicts underscore the ongoing need for concerted efforts to achieve efficient evidence-based policies, particularly in balancing economic interests with environmental conservation goals.

Furthermore, the complex legal and administrative processes involved in implementing the law at various levels, as well as coordinating actions among different Member States, add to the difficulty. Sonja Jähnig emphasized, “A law can only be as good as its practical implementation. We already see that with the Water Framework Directive, aiming at reaching the good ecological status or potential of water bodies. Despite turning into force over 20 years ago, the implementation deficit is still huge. But to give it a positive spin: The NRL could be a booster and role model for the Water Framework Directive activities, if the NRL implementation is done right.”

To manage conflicts, the authors propose using a negotiation process similar to the holistic approaches used in water-scarce regions. This includes establishing flow requirements and comprehensive water planning to ensure sustainable water use and ecosystem restoration.

Challenge 7: Establish methods for identifying integrated connectivity across river networks

The study proposes a pathway to furthering institutional river governance mechanisms with biodiversity monitoring and analysis techniques such as remote sensing and habitat mapping to monitor land use and barrier removal. Novel methods such as environmental DNA (eDNA) surveys could enhance the knowledge of riverscape biodiversity and connectivity across river networks. The authors argue that establishing such monitoring frameworks could lead to the detection of state-changing thresholds, efficient transboundary monitoring, and promote meta-ecosystem thinking for long-term restoration success.

The article provides a scientific output which aims to aid decision-makers reach optimal solutions for evidence-based action. As the process of adoption of the EU Nature Restoration Law is moving forward, there is undoubtedly a need for the establishment of efficient multi-level coordination of efforts to achieve balance between stakeholders and ultimately reach the established biodiversity goals of the EU. The entire article can be accessed here.