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5.8.2. Control measures

Last update: June 2023 Vegetation control A combination of prevention and different mitigation measures for vegetation control is often most successful. It is difficult to eliminate entire populations, so any control measures need consistency and persistence. Regular follow-up checks on sites are essential even if populations are no longer visible. Often IAS can re-occur...

5.8.1. Prevention actions

Last update: June 2023 General information Considering local conditions The geographical and climate conditions often play a role in determining to what extent certain problems occur. Insects or aquatic fauna and flora are often highly adapted to local conditions, in particular temperature and humidity. Shortcuts via canals allow organisms to overcome natural barriers more...

5.6.1. Lighting

Last update: October 2023 Artificial light at night - from infrastructure lighting and possibly from vehicles - has diverse effects on wildlife, such as in reproduction, navigation or communication. It can also affect relationships between species, e.g. pollination or predation interactions. Lastly, artificial lighting throws animals’ biological clocks out of sync, whether they be...

5.6.4. Traffic management

Last update: October 2023 The volume of traffic, which is usually measured as the average number of vehicles per day, and its speed influences the effects that transport infrastructure has on wildlife. Different species can react differently to the infrastructure depending on the number of vehicles (see Chapter 1 – Ecological effects of infrastructure)....

5.6.2. Noise

Last update: October 2023 Noise emitted by traffic causes disturbance both to biodiversity and people (see Chapter 1 – Ecological effects of infrastructure). Noise affects wildlife in different ways, such as behavioural changes due to difficulties with intraspecific communication and/or physiological stress, and noise can travel many kilometres from the infrastructure itself. Different solutions...

5.6.3. Chemical pollution

Last update: October 2023 Pollution by chemicals is one of the most important impacts caused by transport infrastructure during the operation phase. It affects surrounding landscapes but also soil in verges and other Habitats-related to Transport Infrastructure (HTI). Focus is often mainly on reducing pollutants from exhaust emissions, but there are many other sources...

1.3.2. Wildlife mortality

Last update: June 2023 Traffic and infrastructure have likely become the most significant human-induced cause of wildlife injury or mortality (Figure 1.3.3). Each year across Europe, it is known millions of mammals, amphibians, reptiles, birds and an unquantifiable number of invertebrates die due to traffic and infrastructure. Animals are killed on infrastructure due to...

1.3.1. Direct loss of habitat

Last update: June 2023 Transport infrastructure, such as roads, railways, canals, power lines, pipelines, airports and harbours, occupies a large amount of physical space, and leads to a direct and immediate loss of natural habitat. For example, a triple-lane motorway with verges, a hard shoulder and a median strip can easily span more than...

1.3.3. Barrier effect

Last update: June 2023 Linear infrastructures such as roads and railways create movement barriers for most terrestrial wildlife. These barriers can be physical, e.g., infrastructure surfaces and fences, or behavioural, caused by noise, light and other disturbances that repel animals. The impact of these barriers varies between species, but generally they result in reduced...

1.3.4. Edge effects and pollution

Last update: June 2023 Construction, use and maintenance of transport infrastructure and associated areas have various impacts on surrounding ecosystems. They spread pollution (such as noise, light, chemical), change microclimate and groundwater flow, and help in propagating IAS. These impacts affect not only the habitats adjacent to infrastructure (such as road verges and embankments),...

1.3.5. Habitat transformation and corridor effects

Last update: June 2023 The impact created by the transformation of habitats and corridor effect is notable. However, these impacts can be minimised by managing habitats in the infrastructure with biodiversity conservation in mind. HTI are multi-purpose areas alongside roads, railways, under powerlines or at airports. Along roads and railways, they are usually located...

5.7.1. Verges and other green areas

Last update: October 2023 Plans to analyse the whole system of green areas associated with an infrastructure and to define differentiated management to be applied at different sections should be undertaken by the operators. Identifying different zones and types of maintenance is a critical first step which will allow a better integration of these...

5.7.2. Ponds and other blue areas

Last update: October 2023 Transport infrastructure is also associated with aquatic habitats. These include blue areas such as drainage systems which have areas temporarily or permanently flooded, perimetral ditches to collect runoff water, culverts or other types of underpasses to guarantee waterway and river crossing and retention ponds. All of these areas may host...

5.5.12. Amphibian passages

Last update: June 2023 The appropriate size of an amphibian underpass is determined by its length, which depends on the width of the road (Schmidt & Zumbach, 2008). Although some studies have reported amphibians using tunnels as narrow as 0.20 m in diameter (Jochimsen et al., 2004; Lesbarrères et al., 2004; Bain, 2014), there...

5.5.13. At grade fauna passages (level crossing)

Last update: June 2023 For areas where under or overpasses cannot be built (i.e., due to topographic limitations) level crossings, also known as ‘at-grade fauna passages’, may be an alternative to facilitate ungulates crossing. Theoretically, these crossings lead large mammals across the road surface and warn drivers when animals are detected entering the passage...

5.5.10. Adapted culverts

Last update: June 2023 Conventional culverts, usually pipes or rectangular structures (but also large arches in some particular locations), are designed to allow the flow of water and may contain rain water from perimeter drainage or small streams. Some culverts carry water all year round or during long periods. In these areas, adaptations to...

5.5.11. Fish passages

Last update: June 2023 Connectivity of freshwater ecosystems should take account of the movement of freshwater species and also the hydrological flow of nutrients (Ormerod et al., 2011). Therefore, the best way of ensuring freshwater ecosystem connectivity is through viaducts, multiuse underpasses or even adapted culverts. Measures to ensure fish movements in small culverts...

5.5.8. Multiuse underpasses

Last update: June 2023 General description and targets Multiuse underpasses are structures built below linear transport infrastructure which combine wildlife use with human use and/or drainage function. In order to classify a passage as a ‘multiuse underpass’ it must meet the structural requirements of the target species, be located in a suitable and accessible...

5.5.9. Small fauna underpasses

Last update: June 2023 General description and targets Underpasses for small fauna consist of pipes or rectangular structures which are built specifically for some target species. They often target small carnivores (e.g. fox, badger, otter, polecat), but are used by many other small mammals, reptiles, amphibians and invertebrates that can cope with the specific...

5.5.5. Bat crossing devices

Last update: June 2023 In general, the implementation of bat wire-gantries is not recommended since evidence so far has not proven them efficient (Møller et al., 2016 and references therein; Elmeros et al., 2016; Altringham et al., 2020). However, further solid research is needed to evaluate the effectiveness of other bat crossing designs, i.e.,...

5.5.6. Adapted viaducts (Landscape underpasses)

Last update: June 2023 General description and targets Viaducts are large structures usually supported by pillars or arches, which carry linear transport infrastructure and could be easily adapted to enable the preservation of particularly valuable ecosystems and ecological corridors associated with floodplains and river valleys. Movements for a multitude of species, both vertebrates and...

5.5.7. Wildlife underpasses

Last update: June 2023 General description and targets Wildlife underpasses are structures specifically built to provide a safe crossing point for a wide range of species and are suitable particularly for hilly areas or where the infrastructure is situated on an embankment. Common target species are usually ungulates (such as deer and wild boar),...

5.5.2. Landscape overpasses (Ecoducts, Green bridges) and wildlife overpasses

Last update: June 2023 General description and targets Landscape and wildlife overpasses are purpose-built structures which enhance connectivity and provide a safe crossing point for a wide diversity of species. They are usually built over large transport infrastructure such as a highway with several lanes, high-speed railway lines or a combination of infrastructure types....

5.5.3. Multiuse overpasses

Last update: June 2023 General description and targets Multiuse overpasses are structures built over linear transport infrastructure which combine human and wildlife use. In order to classify a passage as a ‘multiuse overpass’ it must meet the structural requirements of the target species, be located in a suitable and accessible environment and be provided...

5.5.4 Tree-top overpasses (Canopy bridges)

Last update: June 2023 Tree-top overpasses or canopy bridges have been used successfully in different parts of the world to mitigate transport infrastructure impacts on arboreal species (Das et al., 2009; Teixeira et al., 2013; Birot et al., 2019). However, in Europe the application of these measures is still limited. Some preliminary studies have...

5.5.1. Types and dimensions of fauna passages

Last update: June 2023 The naming of structures differs between countries. Most commonly used names in Europe are provided in this chapter. Wildlife passages can be divided in two main groups depending if they are located above the infrastructure (overpasses) or below the infrastructure (underpasses). Innovative at level passages are also being implemented. Types...

5.2.4. Fencing and reinforcements for small vertebrates

Last update: June 2023 To avoid small animals (hedgehogs, mustelids, amphibians, reptiles etc.) accessing the infrastructure at sections where it crosses particularly vulnerable habitats, additional reinforcements must be installed at the lower exterior part of a standard fence for large mammals. These fences can also be installed alone (Figure 5.2.14). The entire fenced length...

5.2.10. Fencing and screening for flying fauna

Last update: June 2023 Fencing and screens can be used to avoid bird and bat collisions with vehicles, either by increasing the flight height over the infrastructure or by guiding them to wildlife crossing structures. In both cases, the effectiveness of this mitigation measure will depend on species-specific characteristics. Fences that raise the flying...

5.2.9. Other points of attention

Last update: June 2023 Fences must be thoroughly checked as part of the ordinary road inspection schedule at least once a year and more frequently during the first year after installation, and also in sections of particular conflict or after strong winds, floods or other climate events that can damage fencing (see Chapter 7...

5.2.6. Poles

Last update: June 2023 Fences must be fixed onto sufficiently solid poles, which can be made of galvanized steel (an alloy of 95% Zinc and 5% Aluminium is suitable) rot-proof wood, or even concrete. Steel poles are generally T-shaped or hollow with a square, rectangular or tubular section. The specific characteristics of the poles...

5.2.7. Escape devices

Last update: June 2023 Even with the best fences, infrastructure is never completely sealed off to wildlife. Occasionally, animals may access carriageways at road interchanges, gates, sections damaged due to e.g. landslides, fallen trees, maintenance machinery or even vandalism. It is thus advisable to install escape facilities where required to permit the animals exit...

5.2.8. Cattle grids and gates

Last update: June 2023 Gates could be installed on small roads with sporadic use, e.g. service roads, and those which provide access to a fenced road. The possibility of entry by small animals under the base of the gate should be limited using a concrete threshold accompanied by a rubber base skirt (Figure 5.2.26)....

5.2.5. Adaptation of existing fences and other systems to deter burrowing animals

Last update: June 2023 Where animals, particularly brown bear, wild boar, badger, foxes or rabbits, are accessing infrastructure under existing fences, reinforcements can be installed to make these more robust (Figure 5.2.16). Reinforcements could also be included in the design of new fencing in sections where conflicts with burrowing species are expected. Several materials...

5.2.2. Design and dimensions

Last update: June 2023 There is a lack of published information regarding the effectiveness of the different types of fencing, mesh types, height and length (Rytwinski et al., 2016). The technical prescriptions regarding design and dimensions included in this present chapter are mainly based on knowledge and experience from infrastructure operators and experts from...

5.2.3. Fence material and mesh types

Last update: June 2023 The type of fence to be installed should take account of main target species to be excluded from the infrastructure and must be designed accordingly. The mesh, or any other fence material, should be fixed on the outside of the poles (i.e., away from the road) to prevent a large...

5.2.1. Location and length

Last update: June 2023 In general, wildlife fences should be installed only where there is a high risk of accidents involving wildlife or hotspots of wildlife mortality. In many countries, perimeter fences are an obligatory safety measure along high-speed railways, motorways and other busy roads. Local regulations may also govern the use and features...

7.2. Developing adaptive maintenance of ecological assets

Last update: June 2023 A process in the infrastructure life-cycle Harmonising biodiversity and transport infrastructure is a process that begins in the planning phase and must be delivered by the appropriate construction and maintenance of ecological assets (see Chapter 2 – Policy, strategy and planning). The necessary requirements for each ecological asset to facilitate...

7.2.1. Steps to develop the ecological asset maintenance plan

Last update: June 2023 The maintenance plan should be developed following the steps shown in Figure 7.2.2. Figure 7.2.2 - Main steps to design and develop an ecological asset maintenance plan. Step 1 – Define elements to be maintained The first step to develop a maintenance plan is to identify the ecological assets that...

5.3. Driver warnings

Last update: June 2023 Warning signs aim to influence driving behaviour, reduce speed and increase attention, thus resulting in a reduction in the risk and severity of animal-vehicle collisions (AVC). Several studies have shown that vehicle speed and drivers’ attention are two important factors in wildlife-vehicle collisions. A reduction in speed provides more reaction...

5.4. Wildlife deterrents

Last update: June 2023 Wildlife deterrents in general are intended to cause fear or discomfort to animals and thereby induce a flight response or at least increased alertness. Various acoustic, visual and olfactory signals can be deployed to achieve this. Available evidence to date shows greater effectiveness of acoustic deterrents that rely on natural...

5.1. Introduction

Last update: June 2023 Concern about the loss of biodiversity due to transport infrastructure networks has increased in the last decades, creating an incentive for environmental and transportation organisations to jointly address this problem, develop solutions and mainstream biodiversity within transportation. Solutions need to be applied to both existing and new infrastructure while at...

2.9. References

Last update: June 2023 Borlea, S., Nistorescu, M., Doba, A., Georgiadis, L., & Hahn, E. (2022). Toolkit for Ensuring Sustainable Use and Management of Green Infrastructure in Strategic Environmental Assessments (SEA) and Environmental Impact Assessments (EIA), Danube Transnational Programme DTP3-314-2.3 SaveGREEN project, EPC Environmental Consulting, Bucharest, Romania. Borlea, S., Nistorescu, M., Doba, A., Nagy,...

1.4. Secondary and cumulative effects

Last update: June 2023 Understanding the primary effects of infrastructure and transportation on biodiversity is essential for the implementation of adequate mitigation. However, it is equally important to maintain a wide perspective and see these impacts in their broader context. Small, incremental effects may merge to a more significant but unintended impact on nature...

1.4.1. Landscape fragmentation

Last update: June 2023 The fragmentation of living habitats is recognised as one of the major drivers behind biodiversity loss, worldwide. Wildlife habitats are split, reduced, and isolated from each other by e.g., deforestation, agriculture, urban sprawl, and infrastructure development. Fragmentation typically leads to a reduction in the quality, quantity, and interconnection of suitable...

1.4.2. Cumulative effects

Last update: June 2023 Cumulative effects refer to the gradual build-up of impacts over time including the combined pressures of past, present, and future human activities as well as natural processes. Cumulative effects are additive, multiplicative, or synergetic consequences of these activities and are hence often unpredictable and complex, and generally more significant to...

1.4.3. Mitigating secondary effects

Last update: June 2023 Mitigation of secondary effects typically goes far beyond a single infrastructure project and requires a higher-level guidance such as policies, plan, and programmes, and ideally these should be supported by a Strategic Environmental Assessment (SEA). It must involve multiple stakeholders and consider longer time scales than a single project may...

1.1. Introduction

Last update: June 2023 Mobility is fundamental. It is not only a requisite for economic development but an intrinsic property of life itself. Mobility ensures the exchange of resources, genes, and species, as well as of people and goods. Without sufficient mobility, genetic exchange will cease, populations crumble, trade will fade, and economies shrink....

1.2. Basic concepts

Last update: June 2023 Biodiversity denotes the combined variety of living organisms, ecosystems, as well as the processes that link species and ecosystems. Mobility is such a critical process. It is essential for the survival and well-being of life on Earth as it connects species and ecosystems. Mobility enables organisms to access resources, habitats,...

4.1. Integrated Landscape Management

Last update: February 2024 Sustainable infrastructure development is expected to improve human well-being while avoiding or reducing the impacts on the physical and natural environment. In other words, ensuring the viable coexistence of biodiversity, ecosystem processes, and human activities. In landscape management terms, this means the transport infrastructure life cycle is part of landscape...

4.3.1. Alignment

Last update: February 2024 Route alignment and the design of earthworks should respond to the broad scale of the topography as well as to smaller-scale landforms. The guiding principle is to work with the topography using engineering elements to minimise habitat fragmentation by maximising the opportunities for connectivity below and above the infrastructure (Figure...

4.3.2. Design of specific infrastructure features

Last update: February 2024 The following sections focus on features frequently integrated in transport infrastructure and provide recommendations on how best to design them in order to minimise negative impacts on biodiversity. Earthworks: cutting and embankments Cuttings and embankments are components that, in general, help with route alignment (Figure 4.3.7). Well-designed examples can also...

5.10.2. Measures to reduce risks caused by powerlines

Last update: October 2023 Powerlines cause millions of bird deaths over the world due to collisions and electrocution (Prinsen et al., 2011a; Loss et al., 2014; Guil & Pérez-García, 2022), affecting also other taxa although mainly in other parts of the world (Martín et al., 2022, and references therein). Furthermore, there are other impacts,...

5.10.3. Measures to reduce impacts at airports

Last update: June 2023 Airport management are strictly regulated by the International Civil Aviation Organization (ICAO) for safety reasons. Measures to mitigate impacts of airports on biodiversity are mainly focused on reducing wildlife mortality risks (specifically bird strikes), mainly by keeping wildlife outside airfields or at least, away from operation areas. This section provides...

5.10.1. Measures to reduce risks caused by railway electrification system

Last update: October 2023 Railway systems can have a negative influence on different fauna groups (Borda-de-Água et al., 2017). The most studied and reported impact is wildlife-train collisions (WTC) with mammals. However less is known about how the railway electrification system poses a threat to flying fauna. High-speed railways (HSR) are especially problematic when...

4.2. Biodiversity and infrastructure management at a landscape scale

Last update: February 2024 From a biodiversity management perspective, the first step towards implementing integrated landscape management should be to use landscape ecology science and practice to understand how objects placed in the landscape, such as transport infrastructure, interact with biodiversity. Methods and techniques from this field of ecological research must be implemented as...

7.3. Maintenance requirements for ecological asset and wildlife management

Last update: June 2023 General recommendations Maintenance practice for each ecological asset should be based on guidelines included in maintenance plans (see Section 7.2 – Developing an adaptive ecological asset maintenance plan) and are summarised below. Perform a detailed inventory of elements to be inspected and maintained, including it a GIS database. Include data...

7.3.6. Animal-Vehicle Collisions (AVC) management

Last update: June 2023 Road and railway traffic accidents involving large animals are increasing in many European regions. Removing carcasses is a significant task for maintenance crews, has health and safety implications and high economic costs. To appropriately record and analyse traffic accidents involving animals is the basis for identifying hotspots of wildlife mortality,...

7.3.5. Maintenance of ponds and other drainage elements

Last update: June 2023 Drainage systems in roads and railways include perimeter ditches, retention ponds, culverts, and other transversal structures. Ensuring standards for water evacuation and road safety through drainage systems can be combined with enhancing biodiversity by providing habitats for wildlife. Ponds and ditches can host invertebrates and fish, attract amphibians to breed...

7.3.4. Maintenance of verges and other green areas

Last update: June 2023 The main goal for road verges and medians management is to meet standards for road safety. However, most of these elements can also provide aesthetic landscape value and habitats for wildlife. These green areas, including resting areas and other landscaped zones, help enhance Green Infrastructure when they are managed to...

7.3.3. Maintenance of wildlife warning signs

Last update: June 2023 Wildlife warning signs aim to prevent AVC by influencing driver awareness and behaviour. The effectiveness of signs reduces if drivers become accustomed to them and don’t heed the warning. This problem arises when wildlife warning signs are overused or are not adapted to hazardous road sections. To solve these problems,...

7.3.2. Maintenance of wildlife passages

Last update: June 2023 Wildlife passages (also named fauna passages) are transversal structures located under or over the transport infrastructure constructed or modified to provide safe crossing points for animals and/or to connect habitats on both sides of the infrastructure. Main types of wildlife passages are: Landscape overpasses (Ecoducts/Green bridges) Wildlife and multiuse overpasses...

7.3.1. Maintenance of wildlife fences and screens

Last update: June 2023 Well designed, installed and maintained, fences prevent wildlife getting onto transport infrastructure, reducing mortality and traffic accident risks. Fences must also guide animal movements towards entrances of fauna passages or any transversal crossing structures. Screens are installed to reduce disturbances from traffic (light or noise) at wildlife passages or on...

7.1. Introduction

Last update: June 2023 Definition The prevention of animal-vehicle collisions (AVCs) and complying with environmental legislation are central tenets in the design, construction and operation of the 6 million kilometres of roads and railways across Europe. Equally important is the goal to reduce biodiversity loss which can also have a substantial benefit to human...

6.3.1. Techniques

Last update: June 2023 The techniques most commonly applied to transport infrastructure projects are listed in Table 6.1 and Table 6.2. Here, we do not to present a comprehensive inventory of techniques, but only those that open up new possibilities in terms of conducting fauna or flora inventories to inform monitoring and evaluation. Given...

6.3.2. Innovative approaches applied in transport ecology monitoring

Last update: June 2023 Approaches related to animal ethology In addition to innovative inventory techniques, there are concepts that are increasingly being used in conservation ecology and which could be integrated to any assessment of the impact of infrastructure on biodiversity. Research related to eco-ethology is the main topic of this section, but new...

6.2. Designing and planning a monitoring plan

Last update: June 2023 Monitoring plan framework Designing monitoring plans must be an integral part of the preparation process for the construction or upgrading of transport infrastructure. The monitoring plan needs to cover the entire process from obtaining and analysing data about baseline conditions (i.e., relevant studies or local species data which are often...

6.2.2. Schemes, methods and techniques

Last update: June 2023 Designing a monitoring plan involves the selection and the organisation of schemes or protocols, methods and techniques (Figure 6.2.3). A scheme (also called protocol)is a detailed plan explaining how data must be collected and analysed to answer a research question. It includes:A sampling plan defining procedures for selecting and collecting...

6.2.1. Monitoring across the infrastructure project life cycle

Last update: June 2023 Planning and preparing an appropriate monitoring plan should take place throughout the successive phases of the project, from the design, construction and operation phases to decommissioning (Figure 6.2.2. and see Chapter 2 – Policy, strategy and planning). Design phase: the monitoring plan is usually established in the early design phase...

6.1. The general principles

Last update: June 2023 Basic concepts Environmental assessments are important environmental protection tools. By involving authorities and citizens and incorporating environmental reports, the potential environmental impacts of a planned project can be identified at an early stage and taken into consideration during the decision-making process (https://www.bmuv.de/en/topics/education-participation/participation/environmental-assessments-eia-sea#c19043). Strategic Environmental Assessment (SEA) and Environmental Impact Assessment...

6.1.1. Goals of monitoring and evaluation

Last update: June 2023 Monitoring must be a continuous process interspersed with evaluation events defined during the design phase and applied during construction and operation to enable adaptive management of the infrastructure and the mitigation measures. Some specific monitoring activities provide information to evaluation for determining the effectiveness, or ineffectiveness, of mitigation actions. Other...

3.5. Cumulative effect management

Last update: June 2023 Definition and principle Cumulative effects or impacts are any type of impact coming from an accumulation of direct or indirect significant or insignificant impacts of any type coming from a single project or multiple projects. Cumulative impacts are the result of complex interactions between biodiversity and the landscape, and this...

3.5.2. Cumulative effect management at the project scale

Last update: June 2023 To date, there is no clear, unified method to conduct cumulative impact assessment and management across the EU but some approaches are used depending on the stakeholders involved and the regulatory context: Definition of a threshold can be used to define how much an activity impacts biodiversity and thus to...

3.5.1. Cumulative effect management in Strategic Planning

Last update: June 2023 Addressing cumulative effects due to transport infrastructure should be a strategic planning exercise, and involves their consideration in master plans. Master plans offer the opportunity to handle these complex multiple interactions taking a systemic approach (see Chapter 4 – Integration of infrastructure into the landscape). Whilst master plans are expected...

3.4. Compensation

Last update: June 2023 Scientific evidence shows that compensation as currently applied do not deliver the expected results (Curran et al., 2014; Gelot & Bigard, 2021; Maron et al., 2016). Offsets measures are complex and difficult to achieve (Gonçalves et al., 2015). The ecological outcome is uncertain for many management measures or ecological restoration,...

3.4.3. Compensation strategic and spatial planning

Last update: June 2023 Similar to the avoidance step, anticipation of, and planning offset measures at a strategic level can be a powerful approach to fully implement the mitigation hierarchy successfully. Two different but complementary approaches exist to carry out this planning, either a compensation strategy within a spatialised master plan or the use...

3.4.2. Effective Compensation implementation

Last update: June 2023 Compensation is intended to be the final step in the mitigation hierarchy and is often where the most energy is concentrated, both from a scientific and technical research perspective but also when carrying out implementation. This focus on the last step is a risk to the achievement of NNL as...

3.4.4. Compensation at the project scale

Last update: June 2023 In the context of a project, impact compensation should apply to all the components of biodiversity, such as species diversity, protected habitats, and ecosystem services. This last phase of the sequence involves: A wide variety of methods to assess the equivalence between NNL and NG (see Section 3.4.1 – Equivalence...

3.4.5. Evaluating ‘Compensation’

Last update: June 2023 It is expected that offset measures implemented as a project is developed will be monitored to ensure their efficiency and the information provided will enable corrective measures to be taken if required. The monitoring of compensatory measures still lacks implementation of standardised protocols, including type, frequency, materials, human resources, and...

3.4.1. Equivalence assessment methods

Last update: June 2023 The design of compensation measures must include three steps: Assess the ecological baseline of the impacted site before the project commences. This baseline will serve as a reference for the calculation of equivalence through the mitigation hierarchy implementation. In some cases, degraded areas, for example, the selected baseline can be...

3.3. Reduction

Last update: June 2023 Definition and principle Reduction measures follow avoidance and aim to reduce the permanent or temporary negative impacts of a project on biodiversity, either during the construction phase or the operational phase. Reduction measures can have several effects on the identified impact. They can consist of reducing either the duration of...

3.3.2. Reduction at the project scale

Last update: June 2023 Reduction measures are implemented at the site where the project is developed or in its immediate vicinity. There are two main categories, depending on whether measures relate to either the construction phase or to the operational phase. Those related to the construction phase deal with temporary and/or permanent impacts and...

3.3.3. Evaluating ‘Reduction’

Last update: June 2023 Reduction measures implemented during development of a project are expected to be monitored to ensure their efficiency and to enable corrective measures to be taken where this is not sufficient. Reduction measure monitoring is outlined in Chapter 6 – Evaluation and monitoring.

3.3.1. Reduction in Strategic Planning

Last update: June 2023 Through their strategic and programmatic role, master plans should constitute a framework that guides projects towards both a better understanding of reduction measures and a consistent implementation in their territory. Where the planning document contains prescriptive conditions, mitigation measures should be incorporated to ensure they are implemented. Reduction of environmental...

3.2. Avoidance

Last update: June 2023 The mitigation hierarchy is mostly applied at the project scale, limiting its efficiency towards the objective of reaching NNL (Bigard et al., 2020, Boileau, 2022). This emphasis on the project scale appears to be particularly problematic for the application of the avoidance step (Bull et al., 2022, Kiesecker et al.,...

3.2.1. Avoidance in Strategic Planning

Last update: June 2023 The role of strategic planning in the context of infrastructure development is to 1) evaluate and create a ‘hierarchy of need’ for infrastructure for a given territory, and 2) to identify and evaluate the conflicts between transport infrastructure and biodiversity conservation (see Chapter 4 – Integration of infrastructure into the...

3.2.2. Avoidance at the project scale

Last update: June 2023 There are four key types of avoidance measures that can be implemented at different stages of the project conception (Figure 3.2.2): i) upstream avoidance, ii) geographical avoidance, iii) technical avoidance, and iv) temporal avoidance. These measures are not independent from each other and should be designed iteratively, identifying potential synergies...

3.2.3. Evaluating ‘Avoidance’

Last update: June 2023 Measuring Avoidance Avoidance measurement is a complex process particularly when project-development-cancellation occurs. This is difficult to monitor because ‘no action’ in one place could result in impacts occurring elsewhere, in light of new projects being developed due to the cancellation. Avoidance could also occur in the preliminary stages outside of...

2.3. Design

Last update: June 2023 Phase characteristics The design phase starts after delimitation of the transport corridor is approved and a decision is made that allows construction preparation to start. The first subphase is the route/site selection (alignment), followed by a detailed project, contractor selection and a final building permit. During the design phase, parameters...

2.2. Strategic planning

Last update: June 2023 Current international policies promote the development of a sustainable transport sector, asking to mainstream biodiversity through all transport infrastructure life cycle and preserve or restore ecological connectivity as a mean to achieve the United Nations´ Sustainable Development Goals (UN, 2015). The Kunming-Montreal Global Biodiversity Framework (CBD, 2022) includes it as...

5.9.1. Implications for biodiversity of measures for climate change adaptation

Last update: October 2023 Reduction of flooding effects The number and intensity of floods and flash floods has increased in many parts of Europe and elsewhere during the past decades. This development will continue as climate change progresses. Managers will increasingly have to implement adaptation measures that can reduce damage and costs of flooding...

4.4. References

Last update: February 2024 Baierl, C., Reck, H., & Böttcher, M. (2023). Development and Use of the European Defragmentation Map. BISON - Biodiversity and Infrastructure Synergies and Opportunities for European Transport Network. Horizon 2020. Unpublished report. Catalano, C., Meslec, M., Boileau, J., Guarino, R., Aurich, I., Baumann, N., Chartier, F., Dalix, P., Deramond, S.,...

2.1. Biodiversity within infrastructure life cycle

Last update: June 2023 The life cycle of infrastructure development includes six broad phases: Strategic Planning, Design, Construction, Operation and Maintenance, Upgrade and Adaptation -when required- and Decommissioning, the final step for infrastructure that are no longer required (Figure 2.1.1). This chapter describes how to integrate biodiversity conservation considerations in all steps of this...

6.4. References

Last update: June 2023 Barataud, M. (2012). Ecologie acoustique des chiroptères d’Europe. Identification des espèces, étude de leurs habitats et comportement de chasse. (4th ed.). Muséum national d'Histoire naturelle, Paris; Biotope, Mèze, 360 pp. https://sciencepress.mnhn.fr/fr/collections/inventaires-biodiversite/ecologie-acoustique-des-chiropteres-d-europe-3 Berger‐Tal, O., Blumstein, D. T., Carroll, S., Fisher, R. N., Mesnick, S. L., Owen, M. A., Saltz, D., St....

1.5. References

Last update: June 2023 Bartlett, R. (2019). Visioning Futures—Improving infrastructure planning to harness nature’s benefits in a warming world (p. 62). WWF. https://files.worldwildlife.org/wwfcmsprod/files/Publication/file/3ntj8trz40_WWF_Visioning_Futures_2020_lo_res.pdf?_ga=2.223184411.128269257.1700481335-963127833.1700481335 Benítez-López, A., Alkemade, R., & Verweij, P. A. (2010). The impacts of roads and other infrastructure on mammal and bird populations: A meta-analysis. Biological Conservation, 143(6), 1307-1316. https://doi.org/10.1016/j.biocon.2010.02.009 Borda-de-Água, L., Barrientos,...

3.6. References

Last update: June 2023 Alligand, G., Hubert, S., Legendre, T., Millard, F., & Müller, A. (2018). Théma : Guide d’aide à la définition des mesures ERC. https://www.ecologie.gouv.fr/sites/default/files/Th%C3%A9ma%20-%20Guide%20d%E2%80%99aide%20%C3%A0%20la%20d%C3%A9finition%20des%20mesures%20ERC.pdf Andreakis, A., Bigard, C., Delille, N., Sarrazin, F., & Schwab, T. (2021). Approche standardisée du dimensionnement de la compensation écologique. https://www.ecologie.gouv.fr/sites/default/files/Approche_standardis%C3%A9e_dimensionnement_compensation_%C3%A9cologique_0.pdf Baker, D. J., Maclean, I. M. D.,...

5.11. References

Last update: June 2023 Altringham, J. D., Berthinussen, A., & Wordley, C. F. R. (2020). Generating, collating and using evidence for conservation. In: W. J. Sutherland, P. N. M. Brotherton, Z. G. Davies, N. Ockendon, N. Pettorelli, & J. A. Vickery (Eds.), Conservation Research, Policy and Practice (1st ed., pp. 48–62). Cambridge University Press....

7.4. Maintenance tasks sheets

Last update: June 2023 The ecological assets where specific maintenance guidelines apply are listed below with guidelines provided in the following sheets. Wildlife fences and screens 7.4.1 Maintenance of fencing: meshes and poles7.4.2 Maintenance of fencing: escape devices7.4.3 Maintenance of cattle grids7.4.4 Maintenance of screens installed to reduce disturbances7.4.5 Maintenance of amphibians/small fauna fences...

3.1. Concept, regulation and practice

Last update: June 2023 General concept The mitigation hierarchy is a conceptual framework aimed to mitigate impacts of projects on biodiversity through an iterative process by implementing a series of measures called mitigation measures. This includes avoidance, reduction, and compensation and should be applied to direct, indirect, and cumulative impacts (see Chapter 1 –...

2.8. Future perspectives

Last update: June 2023 Transport infrastructure is facing new challenges that mark future infrastructure management and development: climate change adaptation and digitalisation and deployment of new technologies. Adaptation to climate change  Greenhouse gas emissions are generally considered to be among the main negative impacts of transport on the environment. Within the European Union, there...

2.7.3. Defragmentation of existing infrastructure

Last update: June 2023 Building wildlife passages Building wildlife passages on existing roads, railways or waterways is another special case when adapting existing transportation infrastructure which require to adopt a defragmentation approach (Figure 2.7.2). These measures are required when connectivity between core areas for biodiversity are blocked or long-term monitoring reveals a significant importance...

2.7.2. Bundling

Last update: June 2023 If construction of a new linear transport infrastructure (e.g. road, railway or waterway) is planned to be built in parallel with existing linear infrastructure, the cumulative impact of this pairing of linear transport infrastructure (known as ‘bundling’) on ecological connectivity needs to be appropriately assessed (Figure 2.7.1). The assumption that...

2.7.1. Upgrading

Last update: June 2023 Upgrading projects include works required to increase the capacity of the infrastructure, improve its quality and functionality, apply new technologies and also to adapt the infrastructure to climate change and increase its resilience to natural hazards. This type of projects may present specific situation in which only a change in...

2.5. Operation and maintenance

Last update: June 2023 Phase characteristics The operation phase is the final stage of the process of preparation and construction which usually lasts for decades. During this phase, the infrastructure affects its surroundings with noise and light and pollution from traffic and maintenance, and it creates barriers to movement and splits species populations. Fauna...

2.6. Decommission

Last update: June 2023 Phase characteristics Decommissioning is the final stage in the life cycle of transport infrastructure. It is important to point out that just a few transport infrastructure will reach this stage in its foreseeable future, because most transport infrastructure is continuously maintained or upgraded. Nevertheless decarbonisation goals with deployment of renewable...

2.4. Construction

Last update: June 2023 Phase characteristics The construction phase is the time when the effects of infrastructure development show a real impact on nature. Strict adherence to all measures set to reduce environmental impacts is therefore a key consideration of this phase. The main goal is to implement the plan to protect biodiversity during...