Rozyny Wastewater Treatment Plant, Różyny, Poland

Rozyny is a small wastewater treatment plant located in Różyny, a village in the Pomeranian Voivodeship of northern Poland. The plant serves a population of 26, making it a very small agglomeration under Polish regulations. It is situated near the city of Gdańsk and operates within the broader context of the Vistula River basin. The plant provides secondary treatment, which is the standard level required by the EU Urban Waste Water Treatment Directive for smaller agglomerations. Its designed capacity is 52 m³/day, with an actual discharge volume of 3.71 m³/day, indicating significant spare capacity. The plant is not within 10 km of the coast but is within 50 km, reflecting its inland location. Treated effluent is discharged into local watercourses that eventually drain into the Baltic Sea via the Vistula River or its delta. The plant plays a role in protecting the sensitive coastal and marine environment of the Baltic Sea, which is designated as a sensitive area under the EU directive due to eutrophication risks.

The plant discharges into local streams that flow into the Vistula River, which empties into the Baltic Sea via the Vistula Lagoon or directly into the Gulf of Gdańsk. The Baltic Sea is a brackish, semi-enclosed sea highly susceptible to nutrient pollution. Secondary treatment helps reduce organic load and nutrients, supporting the health of downstream aquatic ecosystems and mitigating eutrophication in the Baltic.