OPINION OF ADVOCATE GENERAL

GEELHOED

delivered on 25 March 2004 ( )

Case C-280/02

Commission of the European Communities

v

French Republic

(Failure by a Member State to fulfil its obligations – Directive 91/271/EEC – Article 5 – Urban waste water treatment – Failure to identify sensitive areas)

I – Introduction

1. In these Treaty-infringement proceedings, the Commission asks the Court to declare that the French Republic has failed to fulfil a number of obligations under Council Directive 91/271/EEC of 21 May 1991 concerning urban waste-water treatment ( ) (hereinafter: ‘the Directive’). The Commission alleges first, that the French Republic failed to identify certain areas as sensitive areas with respect to eutrophication, in the catchment areas of Seine-Normandie, Loire-Bretagne, Artois-Picardie and Rhône-Méditerranée-Corse, and secondly, that it failed to subject to more stringent treatment discharges of urban waste water from agglomerations with a population of more than 10 000 into sensitive areas, or areas which should have been identified as such.

II – Legal context

2. Article 1 states that the Directive regulates the collection, treatment and discharge of urban waste water and the treatment and discharge of waste water from certain industrial sectors; its objective is to protect the environment from the adverse effects of such discharges.

3. Article 2 of the Directive includes the following definitions:

‘1. “urban waste water” means domestic waste water or the mixture of domestic waste water with industrial waste water and/or run-off rain water;

2. “domestic waste water” means waste water from residential settlements and services which originates predominantly from the human metabolism and from household activities;

3. “industrial waste water” means any waste water which is discharged from premises used for carrying on any trade or industry, other than domestic waste water and run-off rain water;

4. “agglomeration” means an area where the population and/or economic activities are sufficiently concentrated for urban waste water to be collected and conducted to an urban waste water treatment plant or to a final discharge point;

5. “collecting system” means a system of conduits which collects and conducts urban waste water;

6. “1 p.e. (population equivalent)” means the organic biodegradable load having a five-day biochemical oxygen demand (BOD5) of 60 g of oxygen per day;

...

8. “secondary treatment” means treatment of urban waste water by a process generally involving biological treatment with a secondary settlement or other process in which the requirements established in Table 1 of Annex I are respected;

...

11. “eutrophication” means the enrichment of water by nutrients, especially compounds of nitrogen and/or phosphorus, causing an accelerated growth of algae and higher forms of plant life to produce an undesirable disturbance to the balance of organisms present in the water and to the quality of the water concerned;

…’

4. Article 5 provides inter alia:

‘1. For the purposes of paragraph 2, Member States shall by 31 December 1993 identify sensitive areas according to the criteria laid down in Annex II.

2. Member States shall ensure that urban waste water entering collecting systems shall before discharge into sensitive areas be subject to more stringent treatment than that described in Article 4, by 31 December 1998 at the latest for all discharges from agglomerations of more than 10 000 p.e.

...

5. Discharges from urban waste water treatment plants which are situated in the relevant catchment areas of sensitive areas and which contribute to the pollution of these areas shall be subject to paragraphs 2, 3 and 4.’

5. Annex II to the Directive, entitled ‘Criteria for identification of sensitive and less sensitive areas’ provides as follows under Section A (‘Sensitive areas’): ‘A water body must be identified as a sensitive area if it falls into one of the following groups:

(a) natural freshwater lakes, other freshwater bodies, estuaries and coastal waters which are found to be eutrophic or which in the near future may become eutrophic if protective action is not taken.

The following elements might be taken into account when considering which nutrient should be reduced by further treatment:

(i) lakes and streams reaching lakes/reservoirs/closed bays which are found to have a poor water exchange, whereby accumulation may take place. In these areas, the removal of phosphorus should be included unless it can be demonstrated that the removal will have no effect on the level of eutrophication. Where discharges from large agglomerations are made, the removal of nitrogen may also be considered;

(ii) estuaries, bays and other coastal waters which are found to have a poor water exchange, or which receive large quantities of nutrients. Discharges from small agglomerations are usually of minor importance in those areas, but for large agglomerations, the removal of phosphorus and/or nitrogen should be included unless it can be demonstrated that the removal will have no effect on the level of eutrophication;

(b) surface freshwaters intended for the abstraction of drinking water which could contain more than the concentration of nitrate laid down under the relevant provisions of Council Directive 75/440/EEC of 16 June 1975 concerning the quality required of surface water intended for the abstraction of drinking water in the Member States ( ) ... if action is not taken;

(c) areas where further treatment than that prescribed in Article 4 of this Directive is necessary to fulfil Council Directives.’

III – Pre-litigation procedure

6. On 22 October 1999, following a protracted exchange of letters with the French authorities on the implementation of the Directive, the Commission sent the French Government a letter of formal notice, in which it drew attention to a number of deficiencies. The Commission regarded the French Republic’s response to the letter as insufficient, and accordingly dispatched a reasoned opinion to it on 10 April 2001; this likewise failed to elicit a response which the Commission considered adequate. The Commission thereupon brought the present action on 30 July 2002.

7. The Commission asks the Court to declare that the French Republic has failed to fulfil its obligations pursuant to Article 5(1) and (2) of and Annex II to the Directive, having

– failed to identify certain areas as sensitive areas with respect to eutrophication, in the catchment areas of Seine-Normandie, Loire-Bretagne, Artois-Picardie and Rhône-Méditerranée-Corse,

and

– failed to subject to further treatment discharges of urban waste water from agglomerations with a population equivalent (p.e.) of more than 10 000 into sensitive areas or areas which should have been identified as sensitive.

8. The French Republic claims that the first plea in law should be dismissed, save in so far as it concerns the River Vistre. The second plea in law should also be dismissed, save in so far as it concerns agglomerations in sensitive areas where certain discharges of urban waste water are still not subject to more stringent treatment.

IV – The subject-matter of the proceedings

9. The Commission’s action rests on two pleas in law. The first plea has two limbs – one deals specifically with the concept of eutrophication; the other, building on the first, concerns deficiencies in the identification of sensitive areas. The second plea in law concerns the French Republic’s alleged failure to subject to more stringent treatment discharges of urban waste water from agglomerations with a population of more than 10 000.

V – First plea in law: the concept of eutrophication and the identification of sensitive areas

A – The concept of eutrophication

Submissions of the parties

10. Article 2(11) of the Directive lists four factors which together constitute eutrophication. These are:

1. enrichment of water by nutrients, especially compounds of nitrogen and/or phosphorus, which

2. causes an accelerated growth of algae and higher forms of plant life, thereby

3. producing an undesirable disturbance to the balance of organisms present in the water and

4. a deterioration in water-quality.

11. Both parties agree that the directive stipulates a causal link between the first two criteria, and between the second criterion and the third and fourth.

12. The French Government emphasises that the four elements are cumulative. The mere fact that one or two occur in a given body of water is not enough to prove eutrophication: the various elements which constitute eutrophication must be shown to be interrelated.

13. The Commission and the French Republic disagree on the interpretation of the third element (an undesirable disturbance to the balance of organisms present in the water). The Commission maintains that the French Government interprets the concept too narrowly: it obtains not only when individual species disappear, or their numbers decrease, but also when one species proliferates while others remain stable.

14. The French Republic responds that, so long as the balance between the other organisms in the water is not disturbed, the proliferation of a single plant species cannot in itself support the conclusion that there has been an undesirable disturbance to the balance of the various organisms present. The Commission, it says, has failed to show cogently why certain phenomena should be labelled undesirable.

15. In its reply, the Commission cites literature describing the undesirable effects of the enrichment of water through nutrients and the resulting accelerated growth of algae and higher forms of plant life. Such undesirable effects may consist in the disruption of food chains within an ecosystem, the disturbance of the balance between the various species present, and a decrease in the oxygen content of the water. In addition, aquatic plants may disappear because large quantities of algae have made the water turbid and prevented light from reaching the seabed. Toxic algae may flourish – these can poison shellfish, endanger human health and cause high fish mortality.

Assessment

16. The aim of the Directive, as is clear from the third and eighth recitals in the preamble and from Article 1, is to protect the environment from the adverse effects of the disposal of both urban and industrial waste water.

17. The fourth recital states that in sensitive areas it is necessary to require more stringent treatment. Article 5(1) and (2) require Member States:

– by 31 December 1993, to have identified sensitive areas according to the criteria laid down in Annex II, and

– by 31 December 1998 at the latest, to ensure that urban waste water entering collecting systems shall before discharge into sensitive areas be subject to further treatment than secondary treatment or an equivalent treatment, for all discharges from agglomerations of more than 10 000 p.e.

18. Annex IIA to the Directive sets out which water bodies are to be identified as sensitive areas. These are:

– water bodies which are found to be eutrophic or which in the near future may become eutrophic if protective action is not taken;

– surface freshwaters intended for the abstraction of drinking water which contains or could contain more than the concentration of nitrate laid down under the relevant provisions of Council Directive 75/440/EEC of 16 June 1975 concerning the quality required of surface water intended for the abstraction of drinking water in the Member States;

– areas where further treatment than secondary treatment or an equivalent treatment is necessary to fulfil Council Directives.

19. The parties differ as to the scope of the concept of eutrophication. The Commission favours a broad interpretation; the French Government understands it more narrowly. That difference is reflected in two ways in the parties’ submissions. The French Government emphasises the causal link which it believes must exist between the various elements of the concept, whereas the Commission asserts that the mere presence of all four elements constitutes sufficient grounds for concluding that the water in question is eutrophic. The parties also differ on how the third element in the definition should be interpreted, the Commission being more readily inclined than the French Government to conclude that the balance between the various organisms present in a body of water has been disturbed.

20. The concept of eutrophication in effect determines the scope of the Directive. As I indicated above at points 17 and 18, Member States are required to identify as sensitive areas water bodies which are found to be eutrophic or which in the near future may become eutrophic if protective action is not taken. Furthermore, urban waste water discharges into sensitive areas must be treated so as to filter out most of the nutrients they contain. The aim of that process is to make the water body less prone to eutrophication. Construing eutrophication broadly will therefore have the effect of increasing the number of water bodies to be identified as sensitive.

21. In determining the proper construction to be placed on the concept of eutrophication, and on the issues of the causal link and destruction of the balance of aquatic life, one must proceed from the aim and structure of the Directive, as well as from the actual terms of Article 2(11).

22. It is apparent from the text, the scheme and the whole thrust of the Directive that its aim is to counter the eutrophication of surface waters by eliminating nutrients from household and urban waste water, thereby forestalling any adverse effects on the environment. In the light of that objective, ‘eutrophication’ should be interpreted in such a way as to ensure that water does not become unsuitable, or less suitable, for consumption, as a result of its quality declining.

23. Moreover, it follows from the scope of the Directive that the concept of eutrophication should not be understood too narrowly. Thus it is not only those water bodies which already are eutrophic, but also (vide Annex IIA) those at risk of becoming eutrophic, which must be identified as sensitive.

24. Article 2(11) indicates that eutrophication consists of four interrelated elements. The first is the enrichment of water by nutrients, primarily nitrogen and/or phosphate compounds. That enrichment leads to the accelerated growth of algae and other higher forms of plant life – the second element. The third and fourth elements relate to the adverse situation which eventually results – an undesirable disturbance of the balance between the various organisms present in the water, and a deterioration in water quality.

25. The above definition is predicated on a causal link between the introduction of nutrients into the aquatic environment, and the eventual deterioration in the quality of the water. Discharges of household waste water increase the amount of nitrogen and phosphate in the water, and make the habitat more nutrient-rich. This has an adverse effect on aquatic life. The increased nutrient load promotes the strong growth of water-plants such as algae and other microscopic plants, which can reduce the water’s oxygen content and lead to an increase in the activity of certain anaerobic bacteria. Moreover, the proliferation of algae may make the water turbid and prevent light from penetrating as deeply as it had before: some fish, and some other organisms, may fail to survive. In such circumstances, a water body’s biological diversity declines sharply.

26. On the basis of the above, I do not believe that there is any need for separate proof of the existence of the causal link: in the light of the definition of eutrophication in Article 2(11) of the Directive, that may simply be presumed.

27. The next question is whether there can be said to be an undesirable disturbance of the balance between various organisms present in a body of water if only one species proliferates excessively while the others remain stable. I believe there can. I have already determined that the objective of the Directive should not be frustrated by interpreting the concept of eutrophication too narrowly. Accordingly it is immaterial whether only one single species proliferates, or more than one. What matters is whether water quality deteriorates as a result of exogenous factors. It is quite possible for that to happen where only one species develops disproportionately.

28. The following example may make this clear. Water affected by the growth of algae which produce toxic substances should be regarded as water the quality of which has deteriorated. Such a toxin can reach humans via the food-chain – for example, through the consumption of mussels in which the toxin has accumulated. Only one (toxic) species of algae has proliferated excessively – yet the biological composition of the water has changed, and the quality of the water has deteriorated. Thus the four elements which constitute eutrophication are present, and the body of water must be identified as being eutrophic.

B – Identification of sensitive areas

29. Since the parties disagree on the concept of eutrophication, they are also at odds on the identification of sensitive areas. The Commission accuses the French Government of failing to identify a sufficient number of sensitive areas.

30. The Commission considers that the French Republic has failed to fulfil its obligations pursuant to Article 5(1) and Annex II by failing to identify the following areas:

– in Seine-Normandie: the Seine bay, the Seine and its tributaries downstream from its confluence with the Andelle;

– in Loire-Bretagne: Lorient harbour, the Elorn estuary, the bay of Douarnenez, Concarneau bay, the Gulf of Morbihan and the bay of Vilaine;

– in Artois-Picardie: the coastal waters and, for mainland waters, the hydrographic system between the canalised Aa and the Escaut on the one hand and the Belgian border on the other hand, the Scarpe downstream from Arras, the Lens Canal downstream from Lens and the whole of the Somme;

– in Rhône-Méditerranée-Corse: the River Vistre and Thau lake.

31. The Commission considers that it has been proved that the abovementioned water bodies either present evidence of eutrophication, or will shortly become eutrophic.

In Seine-Normandie: the Seine bay

Submissions by the parties

32. The Commission considers that the French Republic has infringed Article 5(1) of and Annex II to the Directive by failing to classify the waters of the Seine bay as eutrophic within the meaning of the Directive. The Commission refers inter alia to the excessive development in the bay of two algae, dinophysis (which is toxic), and phaeocystis, caused by the build-up of nutrients.

33. In its application, the Commission confirmed that oxygen levels in the Seine bay had not been found to be too low. Strong tides – a local feature – prevent any major reduction in dissolved oxygen content at the bottom of the bay. The Commission emphasises, however, that it is not only when a water-body has a low oxygen level that its balance can be said to be disturbed and its quality impaired; in circumstances such as those of the present case, the adverse consequences consist in the poisoning of mussels as a result of the proliferation of a toxic alga – dinophysis – and in the foam caused by another alga – phaeocystis – and whipped up by waves.

34. The French Government denies that the water of the Seine bay is eutrophic within the meaning of the Directive. Dinophysis had indeed been found to have developed in certain areas, but only in negligible quantities. The Commission had utterly failed to demonstrate any resulting disturbance to the balance between the various organisms present in the water, or any deterioration in water quality. More specifically, the Seine bay did not suffer from a phenomenon such as algae-induced anoxia, nor was there any causal link between the enrichment of water by nutrients and the excessive development of algae.

Assessment

35. It is, I think, appropriate to recall that the French Government, in the documents it has submitted to the Court, does acknowledge that nutrient-enrichment, and the accelerated development of algae and higher plant species, have both occurred in the Seine bay. However, it disputes any suggestion of a causal link between the two phenomena.

36. As is apparent from point 24, the concept of eutrophication should not be interpreted too narrowly. If a significant deterioration in water quality occurs or is likely to occur as a result of discharges of urban waste water, the area in question is sensitive and must be identified as such. Water affected by the growth of algae which produce toxic substances should be regarded as water the quality of which has been impaired. The fact that the French authorities have acknowledged the presence of dinophysis in the Seine bay, and have not been able to show that it is only present in negligible amounts, compels the conclusion that the French Government has failed to identify the Seine bay as a sensitive area.

In Seine-Normandie: the Seine and its tributaries downstream from its confluence with the Andelle

Submissions of the parties

37. The Commission claims that the French Government erred in failing to identify the Seine and its tributaries downstream from its confluence with the Andelle as sensitive areas. It refers inter alia to two studies by the Institut français de recherche pour l’exploitation de la mer (IFREMER), in which the problems of those waters are described. The studies report that the Seine and its tributaries suffer from acute anoxia as a result of excessive development of algae. This has caused water quality to deteriorate significantly, with all that that entails for aquatic organisms.

38. The French Government’s view is that the Seine and its tributaries downstream from its confluence with the Andelle are not eutrophic within the meaning of the Directive. Since the 1970s, it says, industry made repeated attempts to curb pollution, achieving a 96% reduction in phosphate discharges. However, this had virtually no effect on average oxygen levels in the Poses-Honfleur area, which had risen only one point per year.

39. In its reply, the Commission emphasises that the treatment of urban waste water discharges involves reducing not merely phosphate, but nitrate as well.

Assessment

40. The French Government has not disputed that there has been an accelerated development of algae in the Seine and its tributaries downstream from its confluence with the Andelle, with the undesirable consequence that in large areas of these waters, oxygen levels are too low. The Government therefore does not dispute that the waters in question are eutrophic – it simply states that eliminating phosphate had virtually no effect on oxygen levels in the waters in question.

41. However, the mere fact that a reduction in the emission of one particular nutrient has no actual effect on oxygen levels does not dispense the French Government from its duty to identify eutrophic waters as sensitive areas. It may be a reason for not removing phosphate from waste water during the treatment process – the Directive itself acknowledges that possibility, in Annex II, point i. Yet it cannot justify a failure to fulfil the other obligations which the Directive imposes. Accordingly, I conclude that the French Republic has failed to identify the waters of the Seine and its tributaries downstream from its confluence with the Andelle as eutrophic, and consequently sensitive, areas.

Loire-Bretagne: Lorient harbour, the Elorn estuary, the bay of Douarnenez, Concarneau bay, the Gulf of Morbihan and the bay of Vilaine

Submissions of the parties

42. The Commission considers that Lorient harbour, the Elorn estuary, the bay of Douarnenez, Concarneau bay, the Gulf of Morbihan and the bay of Vilaine should have been identified as eutrophic, or else as waters which in the near future may become eutrophic if protective action is not taken. It takes this view because discharges of urban waste water into those waters contribute significantly to their eutrophication.

43. The Commission considers that national authorities are required to identify a body of water as sensitive if discharges of urban waste water alongside pollution by nitrates from agricultural sources ‘contribute significantly’ to eutrophication. The Commission deduces this (mutatis mutandis) from Standley, ( ) where the Court held that the nitrates directive ( ) applies where the discharge of nitrogen compounds from agricultural sources contributes significantly to pollution.

44. In Lorient harbour, the urban waste water discharge rate is approximately 10%; the Commission believes that this contributes significantly to pollution. Accordingly steps must be taken to curb urban waste water discharges, in addition to what has already been done to protect water against pollution by nitrates from agricultural sources.

45. Another IFREMER report – ‘L’eutrophication des eaux marines et saumâtres en Europe, en particulier en France’ ( ) – states that macroalgae occur in Lorient harbour. The undesirable consequences of such algae are, the Commission believes, superabundantly clear.

46. In the Elorn estuary, the bay of Douarnenez, Concarneau bay and the Gulf of Morbihan, the figures for urban waste water discharges are respectively 21%, 21%, 31% and 33%. The Commission believes that these discharges contribute significantly to the pollution of the waters in question. The bay of Vilaine is likewise eutrophic. The Commission points to the excessive development of a toxic alga (dinophysis), and an excess of phytoplankton.

47. The French Government cannot understand why the Commission, having accepted that such discharges do not contribute significantly to pollution in the case of the bay of Saint-Brieuc, should take a different view in the case of Lorient harbour. Urban waste discharges are at virtually identical levels in the two cases – 8.9% in the bay of Saint-Brieuc, 9.8% in Lorient harbour. The French Government believes that in both cases, the discharges of urban waste water do not contribute significantly to pollution, and that consequently eliminating nutrients from the discharges would not significantly affect the eutrophication status of the area concerned.

48. The Government adds that the French research centre REPHY ( ) has not reported any major development of phytoplankton in Lorient harbour since 1996. Thus one criterion described in the definition of eutrophication – the accelerated growth of algae and higher plant forms – has not been satisfied.

49. The French Government acknowledges that excessive algae development has occurred in the bay of Douarnenez and in Concarneau bay – green tides and excess phytoplankton occur at both sites. However, in both cases the principal cause of pollution is nutrients from agricultural sources, as several studies have confirmed.

50. In regard to the Gulf of Morbihan, the French Government points out that recent studies by IFREMER and others have shown that turbid water and green tides hardly occur there at all.

51. The French Government contends that there is likewise no need to identify the bay of Vilaine as a sensitive area since it receives no direct discharges of urban waste water from agglomerations with more than 10 000 inhabitants.

Assessment

52. Essentially, the point in dispute between the French Government and the Commission is this: in what circumstances can there be said to be a significant contribution to pollution if that pollution is not caused solely by discharges of urban waste water, but also by nitrates from agricultural sources?

53. Two pieces of Community legislation attack the specific problem posed by pollution by phosphates and nitrates, and the ensuing eutrophication: Directive 91/271 concerning urban waste-water treatment, and Directive 91/676/EEC concerning the protection of waters against pollution caused by nitrates from agricultural sources. Both seek to combat the eutrophication of water, one by removing nutrients from urban waste water, the other by reducing the quantity of nitrates from agricultural sources.

54. In my view, once it has been established that a particular body of water is eutrophic or may become so in the near future, and that that situation is caused both by nitrates from agricultural sources and by discharges of urban waste water, it is immaterial what proportion is caused by which source. Together, both contribute to the eutrophication of the water. The two directives, 91/271 and 91/676, complement each other – the obligations arising under them are not mutually exclusive. If discharges of urban waste water, together with nitrates from agricultural sources, cause a particular body of water to become eutrophic, the relevant national authorities must identify it as a sensitive area pursuant to Directive 91/271.

55. It follows, first, that Lorient harbour must be identified as a sensitive area. The study submitted by the Commission indicates that macroalgae have developed there. The French Government has not proved the contrary, but merely denied the existence of excess phytoplankton. Accordingly that Government has not done enough to combat the eutrophication of Lorient harbour.

56. Secondly, the French Government, among its submissions, acknowledged excess algae development in the bay of Douarnenez and Concarneau bay. It has also not denied that the Bay of Vilaine is eutrophic. These, too, should accordingly have been identified as sensitive areas.

57. In regard to the Elorn estuary and the Gulf of Morbihan, the parties have not submitted enough evidence to enable any assessment to be made of the status of these areas. Accordingly the Commission’s plea is unfounded.

Artois-Picardie: coastal and mainland waters

Submissions by the parties

58. The Commission claims that the French Government erred in failing to identify the coastal and mainland waters ( ) in Artois-Picardie as sensitive areas.

59. The Commission maintains that it is apparent from the IFREMER study cited above at point 45 that the Somme bay, Boulogne-sur-mer and Dunkirk are nutrient-enriched, and that, as a result, the coastal waters in Artois-Picardie suffer virtually every year from phaeocystis. In its application, the Commission emphasises that the development of that particular alga is itself enough to disturb the balance between marine organisms. In addition, phaeocystis proliferation in the Somme bay had also led to oxygen deficiency at certain depths.

60. The French Government considers that the existence of a seasonal nutrient cycle and the development of a phytoplankton cycle are insufficient reasons for assuming a causal link between the two. The Government refers also to another IFREMER study – not submitted – reportedly showing no fish or shellfish mortality in the Somme bay. On its own, accelerated growth of phaeocystis does not lead to an undesirable imbalance between the various organisms present in the water: moreover, it produced no toxic substances.

61. In its reply, the Commission refers to the IFREMER study ( ) cited above, which reported the causal link between the nutrient cycle and the phytoplankton cycle.

62. In its rejoinder the French Government submitted a further IFREMER study ( ) reportedly demonstrating that fewer algae occurred at Boulogne-sur-mer and Dunkirk than in the Somme bay.

63. In regard to the mainland waters in Artois-Picardie, the French Government acknowledges that excess development of plant species has occurred, while, however, denying that such phenomena could disturb the balance between the various organisms present in the water. They point out that no damage was sustained by the fish population, and that no toxic algae were reported.

Assessment

64. The French Government has conceded that the coastal and mainland waters in Artois-Picardie suffer from excess development of algae, and that large quantities of nutrients are present in these waters. The studies submitted indicate that the deterioration in water quality here consists of a degradation in the colour, appearance and odour of the water, and in the appearance of a layer of foam on the surface.

65. However, the French Government denies that the various phenomena are causally related. I have already pointed out, at point 25, that if all four of the elements which constitute eutrophication are present, a causal link is presumed to exist between them. In such circumstances it is for the Member State in question to show that there is no causal link. As the French Government has not indicated why they consider that there is no such link, I hold the Commission’s plea to be well founded.

66. It follows that the French Government should have identified the coastal waters in Artois-Picardie as sensitive areas.

Rhône-Méditerranée-Corse: the River Vistre and Thau lake

Submissions of the parties

67. Finally, the Commission accuses the French Government of erring in failing to identify the River Vistre and Thau lake in Rhône-Méditerranée-Corse as sensitive areas.

68. In regard to the River Vistre and Thau lake, the specific point at issue is not so much whether the waters in question are eutrophic, but whether any treatment more stringent than secondary treatment would actually be effective. The French Government concedes that discharges into the Vistre must be subject to treatment beyond secondary treatment. However, it sees no need to apply more stringent treatment to discharges into Thau lake, as eutrophication there has declined since the 1970s.

Assessment

69. Whatever the merits of the French Government’s contention that more stringent treatment is not necessary, it is, I believe, more significant that the Directive requires Member States to identify as a sensitive area any waters which are eutrophic or may become so in the near future. That is the decisive consideration here. This is not the occasion to debate the need for or efficacy of any particular water-treatment method.

70. The French Government has acknowledged that the River Vistre is eutrophic; pursuant to the Directive, therefore, it should have identified it as a sensitive area.

71. Similarly, the Thau lake should have been identified as a sensitive area. The documents submitted by both sides indicate that it has been vulnerable to eutrophication since the 1970s. The French Government’s argument that secondary treatment of the discharges is sufficient to improve its eutrophication level is not cogent. The Directive prescribes more advanced treatment for bodies of water which are eutrophic or may become so in the near future. It follows that the French Government should have identified the Thau lake as a sensitive area.

72. In the light of the foregoing considerations the conclusion must be that the French Republic, by failing to identify as sensitive areas, pursuant to Article 5(1) and (2) of and Annex II to the Directive, certain areas subject to eutrophication in the catchment areas of Seine-Normandie, Loire-Bretagne (with the exception of the Elorn estuary and the Gulf of Morbihan), Artois-Picardie and Rhône-Méditerranée-Corse, has failed to fulfil its obligations under the Directive.

VI – Second plea in law: treatment of discharges of urban waste water in sensitive areas

Submissions of the parties

73. By its second plea in law the Commission accuses the French Government of failing to subject to more stringent treatment discharges of urban waste water from agglomerations with a population equivalent (p.e.) of more than 10 000. The French authorities had conceded that the urban water-treatment plants of 130 agglomerations did not comply with the requirements of the Directive by the deadline of 31 December 1998.

74. In its reasoned opinion, the Commission gave the French Government until 10 June 2001 to repair the omission. Replying on 19 September 2001, the French authorities claimed that in some of the 130 agglomerations discharges were currently subject to the more stringent treatment; according to the Commission, however, only the agglomerations of Vichy, Aix-en-Provence and Mâcon could actually be deleted from the list of 130.

75. In response to the Commission’s charge that currently only three agglomerations were in fact subject to more stringent treatment, the French authorities submitted the names of seven agglomerations which were operational before the deadline of 11 June 2001, and 22 which similarly complied with the requirements of the Directive from June 2001. It claims that only 98 agglomerations failed to comply with the Directive.

Assessment

76. On the Commission’s second complaint – that the French Government erred in failing to subject to more stringent treatment discharges of urban waste water from agglomerations of more than 10 000 p.e. into sensitive areas and consequently infringed Article 5(2) of the Directive – I can be brief.

77. The parties agree that, in respect of 130 agglomerations, the French Government failed to comply with Article 5(2) of the Directive in that the municipal water-treatment plants did not meet the requirements of the Directive by the deadline of 31 December 1998.

78. It is apparent from the submissions of the parties that the water-treatment plants of 10 of the 130 agglomerations became operational before 10 June 2001.

79. Thus the French Government remained in default in respect of 120 agglomerations after June 2001. I consider the Commission’s plea in law to be well founded inasmuch as the municipal water-treatment plants for 120 agglomerations did not satisfy the requirements of the Directive on 10 June 2001.

VII – Conclusion

80. On the basis of the foregoing I am of the opinion that the Court should:

(1) Declare that the French Republic has failed to fulfil its obligations under Article 5(1) and (2) of and Annex II to Council Directive 91/271/EEC of 21 May 1991 concerning urban waste-water treatment, by not identifying certain areas subject to eutrophication in the catchment areas of Seine-Normandie, Loire-Bretagne (with the exception of the Elorn estuary and the Gulf of Morbihan), Artois-Picardie and Rhône-Méditerranée-Corse as sensitive areas, and by not subjecting to more stringent treatment discharges of urban waste water from agglomerations with a population of more than 10 000 p.e. into sensitive areas, or areas which should have been identified as such.

(2) Order the French Republic to pay the costs.