Ceira Wastewater Treatment Plant, Coimbra, Portugal

The Ceira wastewater treatment plant is located in the Ceira parish of Coimbra, Portugal. It serves a population of approximately 2,900 residents, treating domestic wastewater from the local community. The plant is situated inland, away from coastal areas, and operates as part of the municipal wastewater infrastructure for the Coimbra region. 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. With a designed capacity of 3,000 m³/day and a current discharge volume of 483.52 m³/day, the plant operates well below its capacity, indicating room for future growth or seasonal variations. The treated effluent is discharged into the local watershed, which ultimately drains into the Mondego River, one of the major rivers in central Portugal. The Mondego River flows through Coimbra and empties into the Atlantic Ocean near Figueira da Foz. The plant plays a key role in protecting the water quality of the Mondego River and its downstream ecosystems.

The Ceira plant discharges into the Ceira River, a tributary of the Mondego River, which flows through Coimbra and reaches the Atlantic Ocean at Figueira da Foz. The Mondego River basin supports diverse aquatic life and is important for regional agriculture and biodiversity. The plant's secondary treatment helps reduce organic pollution and nutrient loads, safeguarding the river's ecological health and downstream coastal waters.