Oczyszczalnia biologiczna w Osinie - Secondary Wastewater Treatment Plant in Osina, Poland

Oczyszczalnia biologiczna w Osinie is a municipal wastewater treatment plant located in Osina, a village in the West Pomeranian Voivodeship of northwestern Poland. The plant serves a population of approximately 794 residents, placing it in the small agglomeration category under Polish and EU regulations. The plant provides secondary biological treatment, which is the standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. With a designed capacity of 2020 m³/day and an actual discharge volume of 113.21 m³/day, the facility operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into local watercourses that eventually drain into the Baltic Sea via the Odra River basin. The plant plays a key role in protecting the region's surface waters and groundwater from nutrient pollution, supporting the ecological health of the Baltic Sea catchment area.

The plant discharges into small streams that flow into the Odra River basin, which ultimately reaches the Baltic Sea. The Baltic Sea is a semi-enclosed brackish sea sensitive to eutrophication from nutrient inputs. The plant's secondary treatment helps reduce organic load and nutrients, contributing to the health of downstream aquatic ecosystems and the coastal environment.