ONAS Chotrana Wastewater Treatment Plant, Tunis, Tunisia - Municipal Wastewater Facility

ONAS Chotrana Wastewater Treatment Plant is a key municipal facility located in the Tunis region of Tunisia. It is operated by the National Sanitation Office (ONAS) and serves the densely populated capital area, handling wastewater from households and industries. The plant is part of Tunisia's national wastewater management infrastructure, which aims to protect public health and the environment. The plant operates under Tunisia's regulatory framework for wastewater treatment, which aligns with Mediterranean standards. For a facility of this scale, secondary treatment is typically required, and advanced treatment may be implemented to meet discharge standards for sensitive receiving waters. It is a major component of the Tunis sanitation network. The treated effluent is discharged into the Mediterranean Sea via the Lake of Tunis and the Tunis Canal. This coastal discharge supports the ecological health of the Gulf of Tunis, which is an important area for marine biodiversity and fisheries. The plant plays a critical role in reducing pollution loads to the coastal environment, helping to maintain water quality for tourism and local communities.

The plant's treated wastewater flows into the Lake of Tunis, a shallow coastal lagoon connected to the Mediterranean Sea via the Tunis Canal. This water body supports diverse aquatic life and is an important migratory corridor for birds. The Gulf of Tunis receives the discharge, and its coastal waters are used for fishing and recreation. Effective treatment is essential to prevent eutrophication and protect marine ecosystems in this semi-enclosed basin.