VALLO Wastewater Treatment Plant, Guardiagrele, Italy

The VALLO wastewater treatment plant is located in Guardiagrele, a town in the province of Chieti, Abruzzo, Italy. It serves a population of approximately 2,000 residents, making it a small-scale facility within the region's municipal wastewater infrastructure. The plant provides secondary treatment, which is the standard biological treatment required under the EU Urban Waste Water Treatment Directive (91/271/EEC) for agglomerations of this size. The directive mandates secondary treatment for all discharges from agglomerations with a population equivalent (PE) between 2,000 and 10,000, ensuring effective removal of organic matter and suspended solids. The treated effluent is discharged into local watercourses that ultimately drain into the Adriatic Sea via the Aterno-Pescara river system. The plant plays a key role in protecting the water quality of the surrounding watershed, which supports diverse aquatic life and is important for both ecological balance and recreational use in the region.

The plant discharges into the local watershed that feeds into the Aterno-Pescara river system, which flows into the Adriatic Sea. This coastal area supports diverse marine and freshwater ecosystems, including important fish nurseries and migratory bird habitats. The secondary treatment provided helps reduce nutrient loading and organic pollution, safeguarding water quality in the downstream environment.