In this reference from the Irish Supreme Court, the CJEU has once again considered the integrity test under Article 6(3) of the Habitats Directive. That provision requires Member States to withhold agreement to potentially harmful plans or projects unless satisfied, following an appropriate assessment, that the plan or project would not adversely affect the integrity of a Natura 2000 site.


An Bord Pleanála (Planning Board) granted consent to develop the Galway City Outer Bypass on an alignment crossing the Lough Corrib SCI. At the date of the decision the Irish Government had notified the site as a candidate SAC but the Commission had not yet listed it. The works would result in permanent loss of 1.47ha of a total of 270ha of limestone pavement, a priority habitat type listed in Annex I and the main reason for proposing the site’s listing. An Bord took the view that the loss of this small proportion of habitat would not affect the integrity of the site as a whole.


The CJEU rejected An Bord’s contention that EU law was inapplicable: once a Member State has notified a candidate site, the Directive’s protection applies at least until the Commission’s decision ([21]-[23]).

On the substantive issue, the Court reminded itself of the Directive’s scheme of definitions: Articles 1(l) and 3(1) define SCIs and SACs as sites where the habitats in question are to be “maintained or… restored at a favourable conservation status in their natural range.” By Article 1(e), “favourable” conservation status means that a habitat’s “natural range and areas it covers are stable or increasing…”. The Court agreed with A-G Sharpston that “no adverse effect” on a site’s integrity entails “the lasting preservation of the constitutive characteristics of the site… connected to the presence of a… habitat type whose preservation was the objective justifying designation of that site.” ([4]- [8], [37]-[39]).

The Court noted that the precautionary approach to assessment of impacts “applies all the more” where the affected habitat is a priority habitat type ([42]). It held that if the competent authority “concludes that the plan or project will lead to the irreparable loss of the whole or part of a priority natural habitat type whose conservation was the objective that justified the designation of the site… the view should be taken that such a plan or project will adversely affect the integrity of the site” ([47], emphasis added).


Given the UK courts’ notorious reluctance to refer environmental cases to Luxemburg, this decision, relating to similar national legislation, is of real interest. First, the court treated the issue whether, on these facts, there was an adverse effect on integrity as a question of law for the court, not primarily a question for the national authorities’ judgment. Second, it appears that the loss of only part – even a very small part – of a habitat for which the site was designated must be regarded as adversely affecting integrity, at any rate where the habitat is a priority type listed in Annex I.

What is not clear - because the CJEU did not need to decide it - is how far these principles apply to non- priority habitat types. That is important, because the English courts appear to have taken a rather different approach. In R (Merricks) v. Sec of State for Trade & Industry [2006] EWHC 2698 (Admin), [2007] EWCA Civ 1034), the decision-maker’s conclusion on integrity, based on the appropriate assessment, was treated as an ordinary question of administrative judgment, subject only to Wednesbury review. In Hargreaves v. SSCLG [2011] EWHC 1999 (Admin), interference with feeding grounds for pink-footed geese was held not to adversely affect integrity when offset by provision of 12.1ha of new feeding grounds. Neither case dealt with priority habitat types, nor, arguably, involved permanent loss of habitat (they concerned the effects of timelimited consents for wind turbines). Depending on the proper scope of the approach taken in Sweetman, these issues may need to be revisited. But doubtless we will have to await a reference from another Member State before we know the answer.