Kostkow Wastewater Treatment Plant, Kostków, Poland - Secondary Treatment Facility

Kostkow is a wastewater treatment plant located in Kostków, a village in the Podkarpackie Voivodeship of southeastern Poland. The facility serves a population of 2,604 and is part of the municipal infrastructure for the gmina of Jarosław. The plant is situated inland, away from coastal areas, and its operations are regulated under Polish environmental law, which transposes the EU Urban Waste Water Treatment Directive (91/271/EEC). The plant provides secondary treatment, which is the minimum standard required under the EU directive for agglomerations with a population equivalent between 2,000 and 10,000. The designed capacity of the plant is 3,000 cubic meters per day, and the current discharge volume is 371.29 cubic meters per day, indicating a utilization rate well below capacity. This suggests the plant has room to accommodate future growth or seasonal variations. The treated wastewater is discharged into the local watershed, which ultimately drains into the San River, a tributary of the Vistula River. The Vistula flows into the Baltic Sea, making the plant part of a larger transboundary water system. The plant's secondary treatment helps protect downstream water quality and supports the ecological health of the region's rivers and the Baltic Sea.

The plant discharges into the local catchment that feeds the San River, a major tributary of the Vistula River. The Vistula flows northward into the Baltic Sea, a semi-enclosed sea sensitive to nutrient pollution. Secondary treatment reduces organic matter and suspended solids, but does not remove nutrients like nitrogen and phosphorus, which can contribute to eutrophication in the Baltic. The region's agricultural land use may also influence nutrient loads in the watershed.