WATER FRAMEWORK DIRECTIVE

Despite the “autonomous status” and the “general scope” of this obligation to prevent deterioration, the frontier between this obligation and the obligation to enhance the status of bodies of water in order to achieve a good status for theses water bodies by 2015 is not so clear.
In Case C-559/19, the Court states that “as long as the level of overexploitation of a body of groundwater of poor quantitative status does not increase, there cannot be any deterioration of that status which is contrary to the obligation under article 4 (1) b) i) of that directive” . Conversely, measures adopted to achieve a balance between abstraction and recharge of groundwater “such as end to excessive abstraction, and consequently good status of the groundwater body in question, is covered by the enhancement obligation” . In this case, the Court concludes that the documents submitted by the Commission “do not show that overexploitation has increased further, causing a deterioration” of the Almonte-Marismas aquifer since the adoption of the Guadalquivir Basin Hydrological Plan (2015-2021) on January 2016.
The Court was also asked about the criteria to be used to determine if the obligation of non-deterioration was not complied with. According to article 2 (7) of WFD the definition of surface water status is determined by the poorer of the ecological status and the chemical status of the body of surface water. Annex V indicates that a body of surface water is to be classified in the class immediately below as soon as the ratio of the quality elements falls below the level of the current class. However, article 4 (1) of the WFD does not refer to this annex and the so-called “one out all out” rule. The Court therefore considers that “application of the one out all out in conjunction with the status classes theory would also result in waters in the lowest class being excluded from the scope of the obligation to prevent deterioration of their status”. In addition, it underlines that “application of status class theory would result in a weakening of the protection of waters failing within the highest classes”. However, the obligation of non-deterioration “encompasses all change liable to undermine achievement of the principle objective of directive 2000/60”. The Court concludes that there is deterioration of the status of a body of surface water “as soon as the status of at least one of the quality elements, within the meaning of annex V (…) falls by one class, even if that fall does not result in a fall in classification of the body of surface water as a whole. However, if the quality element concerned, within the meaning of that annex, is already in the lowest class, any deterioration of that element constitutes a deterioration of the status of a body surface” .
Despite the difference in the method for determining the status of bodies of water (surface water and groundwater ), the Court considers that “the same principles determine the scope of the concept of deterioration of the status of water, irrespective of the type of water concerned” . Thus, the failure to “observe one the quality elements referred to in point 2.2.2 of Annex V (…) constitutes a deterioration of the chemical status of the body of groundwater” . In addition, “any subsequent increase in the concentration of a pollutant that (…) already exceeds an environmental quality standard or a threshold value set by the Member State also constitutes a deterioration. The values measured at each monitoring point must be taken into account individually” .
More recently the Court has been asked by the French Council of State to precisely define the legal consideration of short-term temporary negative impacts on the state of water bodies in light of the non-deterioration obligation. The Court recalls that unless derogation granted (article 4 (7)), “any deterioration of bodies of water (…) is to be avoided” and it highlights that “to consider that a deterioration of a foreseeable duration of months or even years would not be contrary to article 4 (1) (…) is manifestly incompatible” . The Court concludes that Member states when they assess the compatibility of a particular programme or project with the obligation of non-deterioration they “are not allowed to disregard temporary impacts of short duration with no long-term consequences on water bodies, unless it is clear that such impacts on the status of the bodies of water concerned and cannot lead to deterioration of that status within the meaning of article 4” (1).