COV Spissky Stvrtok Wastewater Treatment Plant, Spišský Štvrtok, Slovakia

COV Spissky Stvrtok is a municipal wastewater treatment plant located in Spišský Štvrtok, a village in the Levoča District of Prešovský kraj, eastern Slovakia. The plant serves a population of 1,548 and has a designed capacity of 2,600 m³/day, with an actual discharge volume of 316.80 m³/day, indicating it operates well below its capacity. The plant provides secondary treatment, which is the standard required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations with a population equivalent (PE) between 2,000 and 10,000. As a small-scale facility, it meets the directive's requirements for biological treatment to reduce organic matter and suspended solids before discharge. The treated effluent is released into local streams that drain into the Hornád River basin, eventually reaching the Tisza River and the Black Sea. The plant plays a key role in protecting the water quality of the Hornád River and its tributaries, which support diverse aquatic life and are used for recreation and irrigation in the region.

The plant discharges into small watercourses that flow into the Hornád River, a major tributary of the Tisza River system. The Hornád River valley is ecologically sensitive, supporting fish populations and riparian habitats. The treated effluent contributes to maintaining water quality in this sub-catchment of the Danube River basin, which ultimately drains into the Black Sea.