Gnojnik SBR Wastewater Treatment Plant, Gnojnik, Lesser Poland

Gnojnik SBR is a secondary wastewater treatment plant located in Gnojnik, a village in the Lesser Poland Voivodeship (województwo małopolskie) of southern Poland. The plant serves a population of approximately 2,142, classifying it as a small agglomeration under Polish and EU regulations. It is situated in a rural area near the Brzesko district, within the drainage basin of the Vistula River. The plant employs secondary treatment, which is the minimum standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The designed capacity is 2,000 cubic meters per day, and the reported discharge volume is 305.42 cubic meters per day, indicating operational capacity well within design limits. As a small plant, it is subject to national monitoring and permitting under Polish environmental law, which implements EU directives. The treated effluent is discharged into local watercourses that ultimately flow into the Vistula River, Poland's longest river, which drains into the Baltic Sea. The plant plays a key role in protecting the local environment by reducing organic pollutants and nutrients, thereby supporting water quality in the Vistula basin and downstream ecosystems.

The plant discharges into the Vistula River basin, which flows northward through Poland and empties into the Baltic Sea via the Gulf of Gdańsk. The Vistula supports diverse aquatic life and is an important migratory corridor for fish species. The surrounding region is predominantly agricultural, so the plant's nutrient removal helps mitigate eutrophication risks in downstream waters, including the Baltic Sea, which is sensitive to nitrogen and phosphorus loading.