COV Velke Kostolany - Secondary Wastewater Treatment Plant in Veľké Kostoľany, Slovakia

COV Velke Kostolany is a municipal wastewater treatment plant located in Veľké Kostoľany, a village in the Piešťany District of Trnavský kraj, western Slovakia. The plant serves a population of 930, classifying it as a small agglomeration under Slovak and EU regulations. It operates secondary treatment, which is the minimum standard required by the EU Urban Waste Water Treatment Directive for inland freshwater discharges. The plant's designed capacity is 1133 m³/day, with an average daily discharge of 190.33 m³/day, indicating it operates well below its design load. As a secondary treatment facility, it removes organic matter and suspended solids but does not include nutrient removal unless specifically required for sensitive areas. Under the EU UWWTD, small agglomerations like this may be subject to less stringent requirements, but national regulations may impose additional standards. The treated effluent is discharged into a local watercourse that ultimately drains into the Váh River basin, a major tributary of the Danube River. The Váh River flows into the Danube, which then reaches the Black Sea. The plant's location inland and its small scale mean its environmental impact is localized, contributing to the protection of downstream aquatic ecosystems in the Danube basin.

The plant discharges into a small watercourse within the Váh River basin, which flows into the Danube River and eventually the Black Sea. The Váh is the longest river in Slovakia and supports diverse aquatic life, including fish species such as barbel and chub. The plant's secondary treatment helps reduce organic pollution, protecting the ecological health of the receiving stream and downstream waters.