Saur Konstancja Sp zoo Wastewater Treatment Plant, Bielawa, Poland

Saur Konstancja Sp zoo is a former wastewater treatment plant located in Bielawa, a district of Konstancin-Jeziorna in the Mazowieckie voivodeship of Poland. The plant was designed with a capacity of 30,000 cubic meters per day and provided secondary treatment, which is the standard biological treatment required under Polish and EU regulations for municipal wastewater. Although the plant is now closed, its design capacity indicates it served a medium-sized agglomeration. Under the EU Urban Waste Water Treatment Directive (91/271/EEC), agglomerations with a population equivalent (PE) over 15,000 typically require secondary treatment, and those in sensitive areas may need tertiary treatment. The plant's secondary treatment level aligns with these standards for its scale. The plant's discharge would have entered local watercourses that drain into the Vistula River basin, eventually reaching the Baltic Sea. The Vistula is Poland's largest river and a vital ecological corridor, supporting diverse aquatic life and migratory fish species. The closure of this plant likely means its service area is now handled by another facility in the region.

The plant is situated in the Vistula River basin, which drains into the Baltic Sea via the Vistula Lagoon. The Vistula is a major European river supporting diverse ecosystems, including wetlands and floodplains that provide habitat for waterfowl and fish. The Baltic Sea is a brackish, semi-enclosed sea sensitive to nutrient pollution, making wastewater treatment in its catchment critical for preventing eutrophication.