Grabownica Wastewater Treatment Plant - Grabownica Starzeńska, Poland

The Grabownica wastewater treatment plant is located in Grabownica Starzeńska, in the Podkarpackie Voivodeship of southeastern Poland. It serves a population of approximately 4,971 people, classifying it as a small to medium agglomeration 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 agglomerations of this size. The designed capacity of 8,523 m³/day indicates that the plant has significant headroom for future growth, as the current discharge volume is 708.79 m³/day. The treated effluent is discharged into local watercourses that eventually drain into the San River basin, a tributary of the Vistula River, which flows into the Baltic Sea. The plant plays a key role in protecting the local watershed from nutrient pollution and safeguarding downstream aquatic ecosystems.

The plant's discharge enters the local drainage network within the San River basin, part of the larger Vistula River system that empties into the Baltic Sea. This region supports diverse freshwater habitats and is important for migratory fish species. The secondary treatment process reduces organic load and suspended solids, helping to maintain water quality in the sensitive Carpathian foothills ecosystem.