Lynetten Wastewater Treatment Plant, Copenhagen, Denmark

Lynetten is a major wastewater treatment plant serving the Danish capital, Copenhagen, and surrounding areas. Located on the island of Amager, it handles wastewater from a population equivalent of approximately 687,000 people, making it one of the largest treatment facilities in Denmark. The plant is situated near the coast and discharges into the Øresund, the strait that separates Denmark from Sweden. As a large agglomeration serving over 150,000 people, Lynetten operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires advanced treatment for discharges into sensitive areas. The Øresund is considered a sensitive area due to its ecological significance, and thus the plant is expected to provide tertiary treatment to reduce nutrients and protect the marine environment. The designed capacity of the plant is 1.00 million cubic meters per day, indicating its substantial scale. The treated effluent from Lynetten flows into the Øresund, which connects the Baltic Sea to the Kattegat and ultimately the North Sea. This water body supports diverse marine life, including fish, seabirds, and benthic communities. The plant plays a critical role in protecting the coastal waters of Copenhagen and the broader Baltic Sea ecosystem from nutrient pollution and other contaminants.

Lynetten discharges treated wastewater into the Øresund, a strait connecting the Baltic Sea to the Kattegat. This marine environment is ecologically sensitive, supporting diverse species such as herring, cod, and migratory birds. Nutrient loading from wastewater can contribute to eutrophication in the Baltic Sea, making advanced treatment essential for protecting water quality and marine habitats.