Pirne Wastewater Treatment Plant

In 2015, the Municipality of Aytos is implementing a project titled: “Construction of a Modular Wastewater Treatment Plant (WWTP) – Pirne Village, Municipality of Aytos.” The project is being implemented with financial support from the Rural Development Program—State Fund “Agriculture.” The total project budget is 359,887 BGN. The plant was commissioned in 2019 and has been transferred to “Water Supply and Sewerage” EAD, Burgas, for management, maintenance, and operation.
The “Pirne” WWTP treats wastewater from the village of Pirne. The plant’s design capacity is 800 PE and a hydraulic load of 129.60 m³/d, or an annual water volume of 47,304 m³/y.

The main treatment process takes place in the following facilities:
• coarse screen, mechanical screening via a fine rotary screen, primary clarifier;
• biological treatment—a biological tank with zones for nitrification, denitrification, and phosphorus removal;
• secondary clarifier;
• aerobic stabilizer.

The treated wastewater is discharged from the WWTP into the Northern Stream, a tributary of the Aytoska River.