When a member state, pursuant to article 4(2)(b) of Council Directive 85/337/EEC, with regard to projects falling within the scope of the discretion under Annex II whether to carry out an environmental assessment (“EA”), established a threshold which was incompatible with the obligations laid down in articles 2(1) and 4(3) of that directive, the provisions of articles 2(1) and 4(2)(a) and (3) of the directive had direct effect, which meant that the competent national authorities had to ensure that it was first examined whether the projects concerned were likely to have significant effects on the environment and, if so, that an assessment of those effects was then undertaken.

The Court of Justice of the European Union (Fifth Chamber) so ruled in a request for preliminary ruling by the Austrian Supreme Administrative Court in proceedings between Salzburger Flughafen GmbH (the operator of Salzburg Airport) and the Umweltsenat (Environmental Tribunal) (“the tribunal”) concerning the obligation to subject certain projects which expanded the infrastructure of the airport to an environmental impact assessment (“EIA”).

After building an additional terminal at Salzburg airport which was situated in an urban area, the airport operator applied to expand the airport further. Austrian national law provided that projects that required an EIA included the modification of airports, “if this is expected to increase the number of aircraft movements … by 20,000 or more per year”. The tribunal, which heard the eventual proceedings, decided that both the extension of the airport infrastructure already in existence, following the construction of the additional terminal, and the expansion proposed in the permit applications required a EIA in accordance with national law and Directive 85/337, which provided by article 4(3), that for the establishment of thresholds or criteria under article 4(2)(b), regard had to be had to, inter alia, the absorption capacity of the natural environment, particularly in densely populated areas. The airport operator appealed against that decision to the Supreme Administrative Court.

THE COURT (FIFTH CHAMBER) said that a threshold such as that in the national provisions was incompatible with the general obligation laid down in article 2(1) of Directive 85/337 for the purposes of correct identification of projects likely to have significant effects on the environment. The establishment of such a high threshold meant that changes to the infrastructure of small or medium-sized airports could never, in practice, give rise to an EIA, despite the fact that such works might have significant effects on the environment. Moreover, with a view to deciding whether an EA had to be carried out, it was necessary to take account of the effects on the environment of both the earlier construction of the additional terminal and the later expansion of the airport area and it could be necessary to take account of the cumulative effect of projects. Accordingly, articles 2(1) and 4(2)(b) and (3) of Directive 85/337 precluded national legislation which made projects which changed the infrastructure of an airport and fell within the scope of Annex II to that directive subject to an EIA only if those projects were likely to increase the number of aircraft movements by at least 20,000 per year.