HAVET & VANHUFFEL – Association d’avocats
In its judgment of 12 June 2026 (Case C-841/24 – Commission v Hellenic Republic), the Court of Justice of the European Union found that the Hellenic Republic had failed to fulfil its obligations concerning collection systems, secondary treatment, enhanced treatment in sensitive areas, and appropriate treatment of urban waste water under Directive 91/271/EEC
This case (C-841/24) concerns an infringement action brought by the European Commission against the Hellenic Republic (Greece) before the Court of Justice of the European Union. The Commission alleged that Greece failed to comply with several obligations under the Urban Waste Water Treatment Directive (Directive 91/271/EEC), particularly regarding the collection and treatment of urban wastewater in numerous Greek agglomerations.
The Directive requires Member States to equip agglomerations above certain population thresholds with wastewater collection systems and treatment facilities. It also imposes stricter requirements for wastewater discharged into environmentally sensitive areas and coastal waters. The objective is to protect public health and the environment by ensuring adequate collection, treatment, and monitoring of urban wastewater.
The dispute originated after Greece reported in 2016 that a significant proportion of wastewater was still being managed through individual systems rather than collective sewerage networks. The Commission requested further information and concluded that many agglomerations were not complying with the Directive. Following a letter of formal notice in 2020 and a reasoned opinion in 2021, the Commission ultimately referred the matter to the Court.
The first complaint concerned 153 agglomerations that lacked compliant wastewater collection systems. Greece relied on individual systems such as septic tanks in many of these areas. The Commission argued that Greece had not demonstrated that collective sewer systems were unnecessary for environmental reasons or disproportionately costly, as required by the Directive to justify such an exception.
The Commission further maintained that Greece had not proven that the individual systems provided a level of environmental protection equivalent to that of proper collection systems. Concerns included leakage risks, insufficient monitoring, inadequate inspections, and the absence of guarantees that wastewater received the required level of treatment before discharge.
Greece argued that its national legislation regulates the construction and operation of individual wastewater systems and that environmental monitoring showed no significant deterioration in water quality. It also emphasized that many wastewater infrastructure projects were underway or had already been completed after the relevant period considered by the Commission.
The Court rejected Greece’s arguments regarding subsequent improvements. According to established case law, compliance must be assessed based on the situation existing at the expiry of the deadline set in the reasoned opinion, namely 2 February 2022. Measures implemented after that date could not eliminate the infringement.
The second complaint concerned 143 agglomerations that failed to ensure proper secondary treatment of wastewater and adequate operation of treatment plants, contrary to Articles 4 and 10 of the Directive. The Court held that where collection systems are deficient, compliance with treatment obligations cannot be established. Four agglomerations also lacked wastewater treatment plants altogether at the relevant date.
The third and fourth complaints related respectively to the agglomeration of Gerakas, located in a sensitive area requiring more stringent treatment, and to thirteen coastal agglomerations where wastewater was not receiving the appropriate treatment required for discharges into coastal waters. The Court found that the deficiencies in collection systems automatically undermined compliance with these stricter treatment obligations as well.
The Court therefore upheld all four complaints brought by the Commission. It ruled that Greece had failed to fulfil its obligations under Articles 3, 4, 5, 7, and 10, as well as Annex I of Directive 91/271/EEC, in numerous agglomerations across the country. As the unsuccessful party, Greece was ordered to bear its own costs and those incurred by the European Commission.
To access the judgment, please follow the link below : https://eur-lex.europa.eu/legal-content/FR/TXT/?uri=CELEX:62024CJ0841