ARIELLI Wastewater Treatment Plant, Ortona, Italy

ARIELLI is a wastewater treatment plant located in the Contrada Arielli area of Ortona, in the province of Chieti, Italy. The plant serves a population of approximately 2,000 people and operates with secondary treatment, which is the standard level required under the EU Urban Waste Water Treatment Directive for agglomerations of this size. With a designed capacity of 2,000 m³/day and an average discharge volume of 395.93 m³/day, the plant operates well below its capacity. The facility is situated near the Adriatic coast, within 10 km of the shoreline, and its treated effluent is discharged into the local watershed, ultimately reaching the Adriatic Sea. The plant plays a key role in protecting the coastal environment of the Abruzzo region. By providing secondary treatment, it reduces organic pollutants and suspended solids before discharge, helping to maintain water quality in the Adriatic Sea and supporting the region's marine and coastal ecosystems.

The plant discharges into the local drainage network that flows into the Adriatic Sea, a semi-enclosed sea with limited water exchange. The coastal waters near Ortona support diverse marine life, including seagrass meadows and fish nurseries. Secondary treatment reduces nutrient loads, helping to prevent eutrophication in this ecologically sensitive coastal zone.