COV Zarnovica Wastewater Treatment Plant - okres Žarnovica, Slovakia

COV Zarnovica is a municipal wastewater treatment plant located in okres Žarnovica, within the Banskobystrický kraj region of central Slovakia. The plant serves a population of 3,556, classifying it as a small agglomeration under EU standards. The plant provides secondary treatment, which is the minimum required by the EU Urban Waste Water Treatment Directive (91/271/EEC) for freshwater discharges from agglomerations of this size. Its designed capacity is 29,215 m³/day, with a current discharge volume of 727.75 m³/day, indicating ample reserve capacity. The treated effluent is discharged into a local watercourse that eventually drains into the Hron River, a major tributary of the Danube. The Danube then flows into the Black Sea. The plant plays a key role in protecting the Hron River basin from nutrient pollution and supporting downstream aquatic ecosystems.

The plant discharges into a tributary of the Hron River, which flows through central Slovakia before joining the Danube near Štúrovo. The Hron River supports diverse fish populations and is used for recreation and irrigation. The Danube, as Europe's second-longest river, ultimately carries the treated effluent to the Black Sea. Protecting the Hron from excessive nutrients is critical for maintaining water quality in the Danube delta and the Black Sea's coastal zone.