Costa de Lavos Wastewater Treatment Plant, Figueira da Foz, Portugal

Costa de Lavos is a former wastewater treatment plant located in the coastal area of Lavos, part of Figueira da Foz municipality in the Coimbra district of Portugal. The plant served a population of approximately 3,000 people and was designed with a capacity of 3,000 cubic meters per day, indicating it was sized for a small agglomeration. The facility is currently closed, and its operational status reflects a transition in local wastewater management. As a secondary treatment plant, Costa de Lavos provided biological treatment to reduce organic matter and suspended solids before discharge. Under Portuguese and EU regulations, secondary treatment is the minimum standard for inland and coastal discharges from agglomerations of this size, as outlined in the EU Urban Waste Water Treatment Directive (91/271/EEC). The plant's discharge volume of 500.19 cubic meters per day suggests it operated below its designed capacity. The plant discharged treated wastewater into the Atlantic Ocean, given its proximity to the coast (within 10 km). The receiving environment includes the coastal waters of the Portuguese western seaboard, which support diverse marine life and are important for local fisheries and tourism. Improving treatment efficiency and environmental protection for the coastal zone.

The treated effluent from Costa de Lavos was discharged into the Atlantic Ocean near the mouth of the Mondego River, which flows through Figueira da Foz. The coastal waters in this area are ecologically sensitive, supporting diverse marine habitats and serving as a nursery for fish species. The Mondego River estuary is a vital ecosystem for migratory birds and aquatic life, and the plant's discharge contributed to nutrient loads in the coastal zone. With the plant now closed, the local watershed benefits from reduced anthropogenic nutrient inputs, aiding the recovery of marine water quality.