Rivers that meander once again. Wetlands that fill with water. Floodplains that are flooded once more after decades of drainage. Renaturation measures are among the most effective tools available to landscape architecture, water management, and nature conservation planning: They restore ecological functions that have been lost due to straightening, drainage, and soil sealing, while simultaneously making a measurable contribution to flood protection, climate adaptation, and biodiversity. Those who understand renaturation understand how the landscape works.

• What defines renaturation measures and how they differ from maintenance, landscaping, and greening
• Which ecological, hydrological, and climatic functions are restored through renaturation
• What types of waterbody, wetland, floodplain, and forest restoration exist and how they differ in terms of planning
• What planning principles, legal frameworks, and technical standards apply
• How renaturation works in practice: from analysis to monitoring success
• What mistakes and misunderstandings frequently occur in practice
• How restoration measures are integrated into urban and peri-urban contexts
• Why restoration, as a planning task, is increasingly becoming a central focus of urban development and infrastructure planning

What renaturation measures are: definition, scope, and basic concepts

Restoration measures refer to targeted planning and construction interventions aimed at restoring degraded or destroyed ecosystems to a near-natural, functional state. The term is derived from the Latin “natura” and essentially refers to the restoration of natural or near-natural structures, processes, and biotic communities. In technical terminology, a distinction is made between renaturation in the narrower sense—that is, active restoration—and passive succession, in which an ecosystem is left to its own devices after the removal of disruptive factors and regenerates independently.

Renaturation measures must be clearly distinguished from related concepts. Landscape conservation preserves existing conditions without making structural changes. Vegetation restoration creates plant cover but does not restore ecological functional relationships. Landscape design, in the sense of open-space planning, primarily pursues aesthetic and use-related goals. Renaturation, on the other hand, is guided by a reference state—that is, a natural or near-natural state that serves as a goal or model—and focuses on restoring system functions: water balance, nutrient cycles, habitat structures, and species communities. This functional focus is the defining characteristic.

Internationally, the term “ecological restoration” has become established, as defined by the Society for Ecological Restoration (SER) in its policy documents. European legislation, in particular the EU Nature Restoration Law, which serves as a binding framework for member states, uses the term “restoration” and links it to quantitative targets for various ecosystem types. In Germany, the Federal Nature Conservation Act (BNatSchG) and the Water Framework Directive (WFD) form the central legal basis for renaturation measures, supplemented by state laws, funding programs, and technical guidelines issued by the states.

Ecological, Hydrological, and Climatic Functions of Renaturation

At the heart of every restoration measure is the restoration of ecosystem functions—that is, the processes that an intact ecosystem performs and that have been disrupted or interrupted by human intervention. These functions can be divided into three broad categories: regulatory functions, habitat functions, and productive functions. Regulatory functions are particularly relevant for planning practice because they have direct effects on the water cycle, climate regulation, and pollutant degradation.

Renaturation measures play a central role in water balance. Straightening watercourses shortens the flow path, accelerates runoff, and reduces the floodplain’s retention capacity. A renaturalized stretch of water with restored meanders, near-natural riparian vegetation, and a connected floodplain area slows runoff, increases groundwater recharge, and buffers flood peaks. This effect is by no means marginal: Studies of renaturalized watercourses show that the retention capacity of a near-natural floodplain can exceed that of a straightened watercourse many times over. This function is becoming significantly more important, particularly in the context of climate change, which is making extreme precipitation events more frequent and intense.

Peatlands are the most efficient terrestrial carbon sinks on Earth. An intact raised bog stores significantly more carbon per unit area than a forest of the same size. Drained and peat-stripped peatlands, on the other hand, become sources of carbon: Aeration of the peat body triggers microbial decomposition, releasing carbon dioxide and nitrous oxide—both of which are greenhouse gases. Peatland restoration—that is, rewetting through the closure of drainage ditches and water retention—stops this process and enables peat formation to resume in the long term. The climate protection benefits of peatland restoration are therefore well-documented scientifically and are being incorporated into national climate protection programs.

For biodiversity, restored areas are of particular importance because they create habitats for species that depend on near-natural structures and can hardly find any habitat left in the intensively farmed landscape. Structure-rich shorelines, deadwood in watercourses, shallow-water zones, reed beds, and softwood floodplains provide habitats for fish species, amphibians, dragonflies, waterfowl, and specialized plant communities. Renaturation measures can thus function as stepping-stone habitats within a larger network of habitats, ensuring the connectivity of habitats across the landscape.

Types of restoration measures: water bodies, bogs, floodplains, forests

Renaturation measures are not a uniform tool but rather a broad spectrum of very different interventions that vary depending on the ecosystem type, the initial condition, and the desired target condition. The most important types in Central European planning practice are water body restoration, wetland restoration, floodplain restoration, and forest restoration.

Watercourse Renaturation

The restoration of flowing water bodies is the most commonly implemented form of restoration in Germany. One of the catalysts for this was the EU Water Framework Directive, which sets the goal of “good ecological status” for all surface waters and requires member states to establish programs of measures. Watercourse restoration involves returning straightened sections of watercourses to a meandering course, removing bank reinforcements made of concrete or rock fill, the creation of riparian buffers, the restoration of fish passage by dismantling transverse structures such as weirs and riverbed sills, and the introduction of deadwood and gravel substrates as habitat structures.

A key planning principle in watercourse restoration is adherence to a watercourse-type-specific model. Each watercourse type—whether a low-mountain stream, lowland river, or sandy stream—has a characteristic morphology, substrate distribution, and biocoenosis. Restoration measures based on this model are more stable in the long term than those that merely appear natural but do not correspond to the water body type in terms of hydraulics and sedimentology. The water body typology developed by LAWA (Länderarbeitsgemeinschaft Wasser) serves as the technical foundation for this in Germany.

Mire Restoration

Mire restoration, also known as mire rewetting or preparation for paludiculture, aims to restore the water balance characteristic of peat bogs. Over the course of the 19th and 20th centuries, drained bogs were extensively drained for agriculture and peat extraction. Restoration is achieved by closing drainage ditches, constructing dams and weirs, and, in some cases, through active planting with peat-forming sphagnum mosses. It is crucial that the water level be kept high on a permanent basis, because peat mosses depend on conditions that are permanently water-saturated.

Floodplain Restoration

Floodplains are the most dynamic landscape features in river basins. Due to dike construction, river channelization, and agricultural use, most German river floodplains have been disconnected from their waterways. Floodplain restoration involves reestablishing flood dynamics—that is, reconnecting the floodplain to the water body through dyke relocation, dyke removal, or the creation of flood basins. This process is complex because it is often associated with land-use conflicts: Agricultural land in the floodplain must be rezoned or compensated for, and infrastructure must be relocated or protected. However, successful floodplain restoration projects—such as those documented along the Rhine, the Elbe, or the Isar—demonstrate that it is possible to combine flood protection, nature conservation, and recreational use.

Forest Restoration

Forest restoration refers to the conversion of structurally poor forests—often spruce monocultures—into structurally rich, site-appropriate mixed forests, or the development of old-growth forest remnants through the cessation of forest use. Measures include the introduction of native tree species, the promotion of deadwood and habitat trees, and the restoration of natural water conditions in the forest. Forest restoration is a long-term process that takes decades to centuries and is often combined with passive succession.

Planning, Methodology, and Monitoring the Success of Renaturation Measures

Renaturation measures follow a structured planning process that begins with a baseline assessment. This involves documenting the current state of the ecosystem, identifying the key factors contributing to degradation, and deriving a realistic target state. Reference conditions are derived from historical sources, comparison sites, and ecosystem typological models. Without this frame of reference, the restoration measure lacks a clear goal, and monitoring success becomes impossible.

During the planning phase, hydrological modeling, field surveys, soil analyses, and species mapping serve as essential foundations. For watercourse restoration, hydraulic calculations are also required to ensure that the planned watercourse morphology remains stable under the given flow conditions. A common mistake in practice is underestimating the system’s inherent dynamics: Renaturalized water bodies do not develop statically according to the planning design, but rather respond to runoff events and alter their morphology. This potential for self-dynamic changes must be factored into the planning, which requires sufficient space for lateral shifts and bank erosion.

Performance monitoring is an integral part of every professional restoration project. It involves verifying whether the target conditions have been achieved and adjusting the measures in case of deviations. Indicators vary depending on the type of ecosystem: For watercourse restoration, macrozoobenthos (invertebrate bottom-dwellers), fish fauna, watercourse morphology, and water chemistry are used. For peatland restoration, water level, sphagnum moss development, and greenhouse gas fluxes are relevant parameters. The WFD mandates standardized biological monitoring for watercourses based on validated assessment methods.

Restoration measures often require a permit under water law, nature conservation law, or building code, depending on the nature and scope of the intervention. A water law permit under the Water Resources Act (WHG) is mandatory for interventions in water bodies and floodplains. Exemptions or exceptions under nature conservation law may be required if measures are carried out in protected areas. Early coordination with permitting authorities is therefore an essential step in the planning process.

Renaturation in Urban and Suburban Contexts

Renaturation measures are not limited to rural areas. In cities in particular, they are gaining importance as a tool for climate adaptation and improving quality of life. Urban waterway restoration, the removal of impervious surfaces, the creation of retention basins, and the restoration of near-natural green spaces are components of blue-green infrastructure that make cities more resilient to heavy rainfall, heat waves, and flooding.

Urban streams, which were channeled into concrete troughs or piped underground in the 20th century, are being restored in many German and European cities. The opening up and restoration of urban streams not only improves the ecological condition of the waterway but also creates attractive open spaces that are highly conducive to leisure and recreation. Well-known examples from German-speaking countries show that renaturalized urban streams can become places of community identity that enhance neighborhoods and improve the urban climate through evaporative cooling. The Isar River in Munich, which underwent a near-natural redesign in the 2000s, is considered a frequently cited reference project for urban waterway restoration.

In the context of urban development, renaturation measures often compete with other land-use demands: housing construction, transportation infrastructure, and commercial use all claim the same land needed for renaturation. Landscape architects and urban planners are called upon to integrate renaturation goals into overarching planning documents—such as land-use plans, landscape plans, and urban development concepts—and to establish them as infrastructure of equal importance. Green and blue infrastructure is not a residual element that remains after other uses have been allocated, but rather a foundation for the city’s functionality.

Common Mistakes and Misconceptions in Planning Practice

A common misconception is to equate renaturation with planting. Simply introducing reeds or woody plants does not constitute renaturation if the structural and hydrological conditions are not established. Plants can only thrive and fulfill ecological functions if the abiotic conditions—that is, water balance, substrate, and nutrient levels—correspond to the target state. Planting without first establishing the appropriate site conditions is generally not sustainable and requires ongoing maintenance, which contradicts the principle of renaturation.

Another mistake is overestimating the self-regulatory capacity of ecosystems in severely degraded situations. Passive succession works well when the factors causing degradation have been eliminated and there is a sufficient pool of species in the surrounding area that can colonize the site. In intensively used agricultural landscapes or urban environments, these conditions are often lacking. Here, active measures such as seeding with native species, introducing structural elements, or targeted maintenance during the establishment phase are necessary.

Restoration measures are sometimes viewed as one-time construction projects that require no further attention once the construction phase is complete. This is a fundamental misconception. Restoration is a process that must be monitored, observed, and adjusted as needed. Especially in the first few years following the project, monitoring and adaptive adjustments are crucial to its success. Projects that are left to their own devices after the construction phase without any assessment of their success often fail to meet their goals or develop in undesirable directions.

Renaturation as a Core Task of Contemporary Landscape Architecture and Planning

Restoration measures have evolved from a niche task in nature conservation into a central planning tool that integrates landscape architecture, water management, climate adaptation, and urban development. The reasons for this are manifold: The ongoing loss of biodiversity, the increase in extreme weather events, climate protection goals related to greenhouse gas reduction, and the legal requirements of the EU Nature Restoration Regulation create a framework in which renaturation is no longer optional but has become a mandatory task.

For landscape architects, this means an expansion of their scope of work: Restoration projects require ecological expertise, an understanding of hydrology, knowledge of planning and permitting laws, as well as the ability to mediate complex conflicts of interest between nature conservation, agriculture, water management, and urban development, and to translate them into viable planning concepts. Collaboration in interdisciplinary teams comprising landscape architects, hydrologists, ecologists, engineers, and planning law experts is not the exception but the rule.

The societal relevance of renaturation measures ultimately lies in their ability to restore ecosystem services on which cities and societies directly depend: clean water, flood protection, climate regulation, soil fertility, and biodiversity. These services cannot be replaced by technical infrastructure—at least not at a reasonable cost. In this respect, renaturation is also an economically sound investment that reduces long-term costs for technical flood protection, water treatment, and climate change adaptation. Anyone who views renaturation measures as a luxury of nature conservation underestimates their systemic importance for functional landscapes and cities.