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., 2009). This is because avoidance relies on a broad scale analysis carried out in anticipation of the project and the selection of scenarios that would result in less impacts on components of biodiversity (Phalan et al., 2018). This shift implies that avoidance must be implemented with anticipation, through a site selection and therefore consideration of a wider landscape context.
Strategic planning is a very powerful tool to enable this anticipation process to plan the mitigation hierarchy, and its first step, avoidance is particularly important (Gordon et al., 2009, Sutherland et al., 2021, Milner-Gulland et al., 2021). Compared to a project scale plan, a master plan covers a scale more relevant for biodiversity, more appropriate with the ecological dynamics that must be considered to apply avoidance. A broader scale assessment also allows the consideration of different projects that may occur within the territory. Moreover, anticipation may allow the study of different scenarios for each project, seeking the lowest impact on biodiversity for all of them (and their cumulative impacts) (Bull et al., 2014, Calvet et al., 2020; Maron et al., 2016). Large scale avoidance can then be designed considering the influence of all these projects, including those that may not go through an Environmental Impact Assessment.
The consultation process is a key component of the strategic planning definition and an opportunity for the integration of biodiversity and the application of avoidance (Boileau, 2022, Lardon & Piveteau, 2005, Sahraoui et al., 2021). It should involve local stakeholders, giving them an opportunity to understand and assimilate the ecological issues of their territory. At the scale of the strategic planning, the consultation process is a strong factor towards the constitution of a lowest impact project for the territory.
Definition and principle
Avoidance measures are designed to prevent any negative impact of a project. It should be considered as a modification of the development project or intended action that prevents any damage to a biodiversity component. As the first step of the mitigation hierarchy, it involves adapting the planning document, including the action, objective, zoning, or prescription. It also includes examining the infrastructure project’s technical or geographical characteristics, to identify and eliminate any negative impacts that the project may cause.
Avoidance is often considered as the least documented step in the mitigation hierarchy as avoidance considerations are not always included in the project design. Even in countries where avoidance is common practice, this crucial step is rarely documented and is sometimes only considered by infrastructure developers during the project’s early phases of conception and only then linked to the pre-assessment phase. The real implementation of avoidance should be considered at the development stage, to support the presentation of a comprehensive implementation of the mitigation hierarchy. This change implies that the consideration and reporting of avoidance in SEA/EIA should begin early in the project design process, to monitor the mitigation decision-making process (for the EIA assessment report and justification needs).
Avoidance requires an in-depth initial stage comprising the identification and the prioritisation of key biodiversity elements and the project´s major impacts; these impact analyses should be shared, widely among all stakeholders. Methodical sharing of knowledge and issues amongst stakeholders facilitates making collective and shared choices of avoidance measures. The governance of the SEA/EIA plays an essential role in implementation. Broadly speaking, the execution of the avoidance step benefits from the establishment of a regional or local transport master plan, and the creation of a consultation process at this scale. Anticipating avoidance as a first, essential step and at a broad scale can enhance results for biodiversity within any project and its acceptability by local stakeholders. To bring about this change, it is essential that infrastructure developers engage with local (and relevant) stakeholders and authorities involved in projects to address the impacts on biodiversity and how to minimise them. This joint approach will lead to new forms of governance involving the national, regional, and local master plan, for SEAs and EIAs.