COV Topolniky Wastewater Treatment Plant, Topoľníky, Slovakia

COV Topolniky is a wastewater treatment plant located in Topoľníky, a village in the Dunajská Streda district of Trnavský kraj, western Slovakia. The plant provided secondary treatment for the local population before its closure. As a secondary treatment facility, COV Topolniky would have met the standard requirements under Slovak and EU regulations for organic matter removal. Plants of this scale in Slovakia typically operate under the EU Urban Waste Water Treatment Directive, which mandates secondary treatment for agglomerations above 2,000 population equivalent. The area drains into the Danube River basin via local streams and canals. The Danube ultimately flows into the Black Sea, making this region part of a major transboundary watershed that supports diverse aquatic ecosystems.

The plant is situated in the Danube River basin, a major European watershed that drains into the Black Sea. Local waterways in the Trnavský kraj region feed into the Danube via the Váh or other tributaries. The area is part of the fertile Danubian Lowland, which supports agriculture and wetlands that provide habitat for migratory birds and fish species.