Zajezierze Wastewater Treatment Plant, Kobylany, Poland

Zajezierze wastewater treatment plant is located in Kobylany, within the gmina Skaryszew in the radomski powiat of województwo mazowieckie, Poland. This facility serves a small population of 346 residents, reflecting its role in a rural or small community setting. The plant provides secondary treatment, which is the standard biological treatment stage required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The designed capacity of 4360 m³/day indicates the plant's infrastructure is sized well above the current discharge volume of 49.33 thousand m³/year, suggesting spare capacity for future growth. The treated effluent is discharged into a local watercourse, ultimately contributing to the Vistula River basin, which drains into the Baltic Sea. The plant's operation helps protect local water quality and supports the ecological health of downstream aquatic environments.

The plant discharges into a local watercourse that is part of the Vistula River basin, Poland's largest river system. The Vistula flows northward into the Baltic Sea, a semi-enclosed sea sensitive to nutrient pollution. Secondary treatment reduces organic load and suspended solids, helping to mitigate eutrophication risks in the Baltic Sea. The surrounding area is predominantly agricultural, so the plant also helps control nutrient inputs from domestic sources.