Osjakow Wastewater Treatment Plant, Mokrsko, Poland | Secondary Treatment

Osjakow wastewater treatment plant is located in Mokrsko, within the Łódź Voivodeship of Poland. It serves a population of 2,264 and operates as a secondary treatment facility, discharging 322.81 cubic meters of treated wastewater per day. The plant's designed capacity is 3,000 cubic meters per day, indicating it operates well below its maximum capacity. As a Polish wastewater treatment plant, Osjakow operates under the EU Urban Waste Water Treatment Directive (91/271/EEC), which requires secondary treatment for agglomerations of this size. The plant's secondary treatment level meets the directive's standards for inland freshwater discharges, ensuring adequate removal of organic matter and suspended solids. The treated effluent from Osjakow is discharged into local watercourses that ultimately drain into the Warta River basin, a major tributary of the Oder River. The Oder flows into the Baltic Sea, making the plant's performance important for both local water quality and the broader Baltic Sea ecosystem, which is sensitive to nutrient pollution.

The plant discharges into the Warta River basin, which flows into the Oder River and eventually reaches the Baltic Sea. The Baltic Sea is a semi-enclosed sea with limited water exchange, making it highly sensitive to nutrient inputs that can cause eutrophication. The plant's secondary treatment helps reduce organic pollution and nutrient loads, supporting the ecological health of downstream rivers and the coastal marine environment.