Seeking coherence among environmental directives

European environmental law consists of a large number of directives and regulations dealing with environmental domains such as air, water, or waste, or with issues such as greenhouse gases, chemicals or industrial emissions. These directives and regulations do not form a comprehensive system of environmental law. Particularly those subjects which have transboundary effects or affect the internal market are regulated at the EU level. In view of the subsidiarity principle (Article 5(3) TEU), other parts of environmental law are left to the Member States. Member States each have their own existing national system of environmental law. Directives have to be transposed into those national systems by the Member States. It is in this process of transposition that flaws in or discrepancies between directives are likely to be felt. In order to facilitate their implementation, it is important that directives form a coherent system: provisions from different directives should not clash, and preferably the same terms and definitions should be used. This enables the Member States to implement the directives in a general act in the field of environmental law, and moreover does not force them to differentiate between terms coming from different directives. This chapter will first pay attention to the implementation of environmental directives (Section 1). Then, several environmental directives will be used as an illustration of the problems which may arise when there is a lack of coherence between directives (Section 2).