FREDERIKSHAVN Wastewater Treatment Plant, Frederikshavn, Denmark

FREDERIKSHAVN is a wastewater treatment plant located in Frederikshavn, a coastal city in the Region Nordjylland of Denmark. The plant serves a population of approximately 39,000 people, classifying it as a medium-sized agglomeration under EU regulations. Its location near the Kattegat sea places it in a sensitive coastal environment. As a Danish facility, the plant operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for agglomerations of this size. For discharges into sensitive coastal areas, more stringent treatment may be mandated. The treated effluent is discharged into the Kattegat, a sea area connecting to the North Sea and ultimately the Atlantic Ocean. This coastal discharge requires careful management to protect marine ecosystems, including fish populations and benthic habitats. The plant plays a key role in safeguarding the local marine environment from nutrient pollution.

The plant discharges into the Kattegat, a shallow sea between Denmark and Sweden that connects to the North Sea. This marine area supports diverse aquatic life, including important fish stocks and migratory species. Nutrient discharges from wastewater can contribute to eutrophication, so the plant's treatment level is critical for maintaining water quality in this ecologically sensitive coastal zone.