COS w Herbach Wastewater Treatment Plant, Herby, Silesia, Poland

COS w Herbach is a wastewater treatment plant located in Herby, within the Silesian Voivodeship of southern Poland. The facility serves a population of approximately 1,735 residents, placing it in the small agglomeration category under Polish and EU regulations. The plant is situated in a region characterized by mixed urban and rural landscapes, with proximity to the historic town of Częstochowa. The plant provides secondary treatment, which is the minimum standard required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for discharges into freshwater bodies. With a designed capacity of 4,386 m³/day and an actual discharge volume of 247.38 m³/day, the facility operates well below its capacity, indicating potential for future growth or seasonal variability. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The treated effluent is discharged into local watercourses that eventually drain into the Vistula River basin, which flows northward to the Baltic Sea. The plant plays a key role in protecting the region's surface waters from nutrient pollution, supporting aquatic life and downstream ecosystems. Its operation is subject to Polish environmental permits aligned with EU directives, ensuring compliance with discharge standards.

The plant discharges into local streams that are part of the Vistula River basin, one of Poland's major river systems. The Vistula flows through central Poland and empties into the Baltic Sea via the Gdańsk Bay. The watershed supports diverse aquatic habitats and is important for migratory fish species. The region's moderate climate and mixed land use mean that nutrient loading from wastewater must be carefully managed to prevent eutrophication in downstream lakes and coastal waters.