Grabow Wojtostwo Wastewater Treatment Plant, Giżyce, Greater Poland Voivodeship

Grabow Wojtostwo is a municipal wastewater treatment plant located in the village of Giżyce, within the Gmina Grabów nad Prosną in the Greater Poland Voivodeship. The plant serves a population of 5,757, classifying it as a small to medium agglomeration under Polish and EU regulations. Its location in a rural area of west-central Poland places it within the Prosna River catchment, part of the larger Oder River basin. The plant provides secondary treatment, which is the standard required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size discharging into freshwater. Secondary treatment typically involves biological processes to reduce organic matter and suspended solids. The designed capacity of 6,171 m³/day indicates the plant is sized to handle peak flows, with current discharge averaging 820.86 m³/day, suggesting ample reserve capacity. The treated effluent is discharged into local watercourses that eventually feed into the Prosna River, a tributary of the Warta River, which flows into the Oder River and ultimately the Baltic Sea. The plant plays a key role in protecting the Prosna River's water quality, supporting aquatic life and downstream ecosystems in the Oder basin. Its operation aligns with Poland's obligations under the EU Water Framework Directive to achieve good ecological status in surface waters.

The plant discharges into the Prosna River catchment, which flows into the Warta River, a major tributary of the Oder River. The Oder River drains into the Baltic Sea, making this plant part of a transboundary basin. The Prosna River supports diverse aquatic habitats and is important for regional biodiversity. The plant's secondary treatment helps reduce nutrient loads, mitigating eutrophication risks in downstream waters.