GLEREYAZ Wastewater Treatment Plant, Châtillon, Aosta Valley, Italy

GLEREYAZ is a wastewater treatment plant located in Châtillon, within the Aosta Valley region of northwestern Italy. The facility serves a population of approximately 5,700 people, supporting the local community in this Alpine valley setting. The plant is situated near the Autostrada della Valle d'Aosta, reflecting its role in the region's infrastructure. As a plant serving a small agglomeration, GLEREYAZ operates under Italy's implementation of the EU Urban Waste Water Treatment Directive (91/271/EEC). For settlements with a population equivalent between 2,000 and 10,000, the directive requires appropriate treatment to protect receiving waters. The plant's treatment processes are designed to meet these standards, ensuring compliance with national and European regulations. The treated effluent from GLEREYAZ is discharged into the local watershed, which ultimately drains into the Dora Baltea River. This river flows through the Aosta Valley and joins the Po River, one of Italy's major waterways, before reaching the Adriatic Sea. The plant plays a key role in protecting the water quality of this Alpine river system and the downstream Po basin.

GLEREYAZ discharges into the Dora Baltea River, a tributary of the Po River, which flows into the Adriatic Sea. The Aosta Valley watershed is characterized by Alpine ecosystems and supports diverse aquatic life, including fish species adapted to cold, oxygen-rich waters. The plant's treatment helps maintain water quality in this sensitive mountain environment, preventing nutrient enrichment and protecting downstream habitats.