Environmental Assessments in the EU’s environmental policy

As already mentioned, there are significant synergies between the EIA/SEA Directives and substantive elements of EU environmental law. The prior assessment of projects or plans/programmes may need to comply with overlapping obligations stemming from the Habitats Directive (92/43/EEC), the Water Framework Directive (2000/60/EC), or even both. As a consequence, a proposed project affecting a water body might not only require assessments related to Article 4(7) of the Water Framework Directive; it might also lead to the need for assessments in relation to a Natura 2000 site hosting such a water body under Article 6(3) and 6(4) of the Habitats Directive.

The Water Framework Directive and the Habitats Directive allow for the use of exemptions under certain conditions, based on previous assessment. In both cases, the authorities need to carry out the relevant procedures and tests under each Directive. Although there are some differences in the procedures and conditions, there are also potentials for synergies and streamlining of the related data collection and assessments. In other words, for example, carrying out an EIA does not guarantee fulfilment of Article 4(7) of the Water Framework Directive, but it could contribute if the assessments are streamlined. Note that also the requirements on public participation can be relevant in that context.

As such grouping of assessments and streamlining can be efficient and reduce the work load. Coordination with the EIA/SEA process is not only advisable but often less expensive and more effective. However, if the conditions of one Directive are fulfilled but not of the other, then the authorities may not authorise the project because in such a case the project would still infringe EU legal provisions (see Case C-43/10 Nomarchiaki Aftodioikisi Aitoloakarnanias and Others).

The key requirements for the protection and management of Natura 2000 sites are set out in Article 6 of the Habitats Directive. In particular, any plan or project likely to damage a Natura 2000 site has to be subject to an appropriate assessment within the meaning of Article 6(3) of the Habitats Directive and can only be authorised if it does not affect the integrity of the site, or if it fulfils the conditions for derogations under Article 6(4) of the Habitats Directive.

The step of the Article 6(3) process where it is determined whether a project or a plan is likely to cause significant effects to a Natura 2000 site, either alone or in combination with other plans and projects, corresponds to screening. Even though not explicitly mentioned, scoping is accepted as good practice and aims to precisely identify the potential issues that the assessment should cover, as well as the appropriate information to gather.

The focus of the assessment is narrower that standard EIA – and emphasises the conservation objectives of the site. Furthermore, the mitigation measures form part of normal practice and are considered in the context of the Natura 2000 assessment. These are measures aiming to remove, pre-empt or reduce the potential impacts on the Natura 2000 sites in question. As the final part of the Article 6(4) requirements, the compensatory measures must be provided to offset the negative effects of a plan or project so that the overall ecological coherence of the Natura 2000 network is maintained. Mitigation measures are particularly relevant when assessing alternatives under the EIA Directive, both with a view to strengthening the feasibility of projects, and to improving the project’s design. The EIA Directive does not define or explicitly differentiate between mitigation and compensation. Nonetheless, when different types of mitigation actions under EIA are being considered, evolving good practice favours measures taken at source (on-site) over those 'off site' and promotes the application of the so-called ‘mitigation hierarchy’.