Polczyn Zdrój Wastewater Treatment Plant, Ostrowąs, West Pomeranian Voivodeship

The Polczyn Zdrój wastewater treatment plant is located in Ostrowąs, a village within the gmina of Połczyn-Zdrój in the West Pomeranian Voivodeship of northwestern Poland. The facility serves a population of approximately 38,500, classifying it as a medium-sized agglomeration under EU regulations. Its location near the historic spa town of Połczyn-Zdrój places it in a region known for its natural springs and tourism. As a Polish facility serving over 10,000 people, the plant is subject to the EU Urban Waste Water Treatment Directive 91/271/EEC, which requires secondary biological treatment for all discharges from agglomerations of this size. The directive also mandates more advanced treatment if the receiving waters are designated as sensitive areas, such as those prone to eutrophication. The plant's compliance with the directive ensures a minimum level of pollutant removal before discharge. The treated effluent from the plant is discharged into local watercourses that eventually drain into the Parsęta River basin, which flows northward into the Baltic Sea. The Baltic Sea is a semi-enclosed brackish sea highly sensitive to nutrient pollution, making effective wastewater treatment critical for reducing eutrophication. The plant's operation contributes to protecting both local streams and the broader marine environment.

The Polczyn Zdrój plant discharges into the Parsęta River catchment, which flows into the Baltic Sea near Kołobrzeg. The Baltic Sea is a brackish water body with limited water exchange, making it highly susceptible to nutrient enrichment from wastewater and agricultural runoff. Effective treatment at this plant helps reduce nitrogen and phosphorus loads that could otherwise contribute to algal blooms and oxygen depletion in coastal waters. The region's glacial landscape and numerous small lakes also mean that local streams are ecologically sensitive, supporting diverse aquatic life and migratory fish species.