Mechaniczno Biologiczna Wastewater Treatment Plant, Zarębki, Poland

Mechaniczno Biologiczna is a wastewater treatment plant located in Zarębki, within the gmina Zembrzyce in województwo małopolskie, Poland. It serves a small community of 1,171 people, reflecting its role in rural wastewater management in the Lesser Poland region. The plant provides secondary treatment, which is the standard biological treatment stage required under Polish regulations aligned with the EU Urban Waste Water Treatment Directive. For small agglomerations under 2,000 population equivalent, appropriate collection and treatment systems are mandated to protect local water quality. The treated effluent is discharged into local watercourses that ultimately drain into the Vistula River basin, which flows northward to the Baltic Sea. The plant's operation helps safeguard the ecological health of small streams and rivers in the Skawa catchment area, supporting aquatic biodiversity and downstream water quality.

The plant discharges into local streams that are part of the Skawa River catchment, a tributary of the Vistula River. The Vistula flows through Poland to the Baltic Sea, making the plant's treatment important for reducing nutrient loads that could contribute to eutrophication in coastal waters. The surrounding area features forested hills and agricultural land, where maintaining clean waterways supports both wildlife and local communities.