A recent judgment (Holohan v An Bord Pleanála) has been passed down by the Court of Justice of the European Union (CJEU) following a request from the High Court (Ireland) for a preliminary ruling concerning the interpretation of Council Directive 92/43/EEC (‘the Habitats Directive’) and Directive 2011/92/EU (‘the EIA Directive’). The key rulings from the judgement are summarised below.
Habitats Directive Rulings
In relation to the Habitats Directive, the judgement ruled (emphasis added):
“an ‘appropriate assessment’ must, on the one hand, catalogue the entirety of habitat types and species for which a site is protected, and, on the other, identify and examine both the implications of the proposed project for the species present on that site, and for which that site has not been listed, and the implications for habitat types and species to be found outside the boundaries of that site, provided that those implications are liable to affect the conservation objectives of the site.”
This ruling emphasises the need for Appropriate Assessments to consider effects on habitats and species outside of Natura 2000 sites, where these are impacted by development and may have implications for the conservation objectives of the protected sites.
The judgement also ruled that (emphasis added):
‘…..the competent authority is permitted to grant to a plan or project development consent which leaves the developer free to determine later certain parameters relating to the construction phase, such as the location of the construction compound and haul routes, only if that authority is certain that the development consent granted establishes conditions that are strict enough to guarantee that those parameters will not adversely affect the integrity of the site.’
The Advocate General’s Opinion, which sets out further detail on this matter, clarifies that such certainty is only achieved when there is ‘no reasonable scientific doubt’ that the parameters left to be decided later by the developer will not affect the integrity of the protected site.
These rulings emphasise the strict nature of the tests that must be passed in order for a plan or project to satisfy the requirements of the Habitats Directive, including the detailed information and high level of certainty required to inform an Appropriate Assessment.
The fourth ruling of the Holohan judgement relates to the EIA Directive. This ruling states:
‘4. Article 5(1) and (3) of, and Annex IV to, Directive 2011/92/EU of the European Parliament and of the Council of 13 December 2011 on the assessment of the effects of certain public and private projects on the environment, must be interpreted as meaning that the developer is obliged to supply information that expressly addresses the significant effects of its project on all species identified in the statement that is supplied pursuant to those provisions.’
This ruling is informed by the Advocate General’s Opinion, which sets out further detail on this matter (emphasis added):
‘84. Since the fauna and flora are made up of the various species present [on the site concerned], the developer must provide information on the effects on certain species. However, that obligation does not cover all effects on all species present, but only the main effects. That restriction to the main effects is confirmed, moreover, by the fact that, under Article 5(1) of the EIA Directive, the developer is required to provide only information which is relevant and which he can reasonably be required to compile.
The key requirement of this ruling is therefore that potentially significant effects on flora and fauna are identified. This largely relates to protected species, although consideration should be given to other species where relevant in terms of a likely significant effect. However, effects on widely distributed species would not typically constitute a significant effect.
 Brian Holohan and Others v An Bord Pleanála. Judgment of the Court (Second Chamber) of 07/11/18. Case C-461/17.
 Opinion of Advocate General Kokott – Case C-461/17 (delivered on 07/08/2018)
 Opinion of Advocate General Kokott – Case C-461/17 (delivered on 7 August 2018)