The purpose of the project is to ensure that the wastewater from Çayırhan (Nallıhan), currently being discharged into the Sarıyar Dam Lake, undergoes advanced biological treatment, including nitrogen and phosphorus removal. This aims to prevent long-term negative environmental impacts.

The primary objectives of the project are the treatment of domestic wastewater from Çayırhan Neighborhood, Nallıhan District, Ankara Province, in compliance with regional and national characteristics, as well as existing laws and regulations, in the most economical and technical manner, and the discharge of the treated water.

Geotechnical studies have been conducted for this facility, and ground improvement projects have been prepared as part of the project scope.