Zakrucze Wastewater Treatment Plant, Bolmin, Poland

Zakrucze is a municipal wastewater treatment plant located in Bolmin, within the świętokrzyskie province of Poland. It serves a population of approximately 5,700 people, placing it in the small-to-medium agglomeration category under Polish and EU regulations. The plant provides secondary treatment, which is the minimum standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for inland discharges from agglomerations of this size. Its design capacity is 8,400 m³/day, with an average daily discharge volume of 812.73 m³/day, indicating operational headroom. Treated effluent is discharged into the local watershed, which ultimately drains into the Vistula River basin and then to the Baltic Sea. The plant plays a key role in protecting downstream water quality and supporting the ecological health of the region's rivers and coastal waters.

The plant discharges into the local catchment of the Vistula River basin, which flows northward through Poland into the Baltic Sea. The downstream environment includes sensitive aquatic habitats that benefit from reduced nutrient and pollutant loads. Secondary treatment helps mitigate eutrophication risks in the Baltic Sea, a semi-enclosed sea vulnerable to algal blooms.