Ocsanalos Szennyviztisztito Telep - Advanced Wastewater Treatment in Onga, Hungary

Ocsanalos Szennyviztisztito Telep is a small advanced wastewater treatment facility located in the village of Ócsanálos, part of Onga in Borsod-Abaúj-Zemplén county, northern Hungary. The plant serves a population of 130 and has a designed capacity of 200 m³/day, with an actual discharge volume of 15.33 m³/day. As an advanced treatment plant, it goes beyond secondary treatment to remove nutrients and other pollutants, aligning with Hungary's implementation of the EU Urban Waste Water Treatment Directive (91/271/EEC). For small agglomerations under 2,000 population equivalent, the directive requires appropriate treatment, and Hungary applies advanced standards in sensitive areas. The plant's treated effluent is discharged into local waterways that drain into the Sajó River, a tributary of the Tisza River, which flows into the Danube and ultimately the Black Sea. This contributes to protecting the Tisza River basin's aquatic ecosystems and downstream water quality.

The plant discharges into the Sajó River catchment, part of the Tisza River basin, which flows into the Danube and reaches the Black Sea. The Tisza basin supports diverse aquatic life and is an important ecological corridor in Central Europe. Advanced treatment helps reduce nutrient loading, protecting downstream waters from eutrophication.