Greece is facing European Union court action for failing to ensure that urban wastewater is properly treated.

The case concerns areas where between 2,000 and 15,000 people live. The European Commission said that Greece was first warned about the matter in 2010, and although many of the original concerns have since been addressed, the scale of the remaining problems has led the Commission to refer the case to the E.U.'s Court of Justice.

The Urban Waste Water Treatment Directive (91/271/EEC) requires member states of the European Union to ensure that towns and cities properly collect and treat their urban wastewater. As the Commission explained, untreated wastewater can be contaminated with harmful bacteria and viruses, presenting a risk to public health. It also contains nutrients such as nitrogen and phosphorous which can damage rivers, lakes and the ocean by promoting excessive algae growth.

When the legislation was introduced in 1991, member states were given until the end of 2000 to ensure appropriate treatment for wastewater from large towns and cities, and until the end of 2005 for discharges from smaller residential areas.

However, progress has been slow in Greece and the latest reports from the Greek authorities show that appropriate treatment facilities are still lacking in five areas: Prosotsani, Doxato, Eleftheroupoli, Galatista and Vagia.

Additionally, for three other areas (Polichronou, Chanioti and Desfina) the Commission said it believed that the data submitted was either incomplete, or showed a failure to comply with the appropriate standards.