Suurupi Wastewater Treatment Plant, Harju maakond, Estonia

Suurupi wastewater treatment plant is located in Harju maakond, Estonia, serving the village of Suurupi and surrounding areas. With a population equivalent of 1,100, it is a small-scale facility that provides advanced treatment to protect the local environment. The plant has a designed capacity of 10,000 m³/day, indicating room for future growth. As an advanced treatment plant, Suurupi goes beyond secondary treatment to remove nutrients and other pollutants, meeting stringent standards under Estonian and EU regulations. Estonia, as an EU member state, implements the Urban Waste Water Treatment Directive (91/271/EEC), which requires appropriate treatment for discharges into sensitive areas. The plant's advanced level suggests it operates in a sensitive catchment or coastal zone. The treated effluent is discharged into the Baltic Sea, a semi-enclosed sea with limited water exchange, making it sensitive to nutrient pollution. The plant's advanced treatment helps reduce eutrophication risks in the Gulf of Finland and the broader Baltic Sea, supporting marine biodiversity and coastal water quality.

The plant discharges into the Baltic Sea via local coastal waters. The Baltic Sea is a brackish, semi-enclosed sea with limited water exchange, making it highly sensitive to nutrient inputs that can cause algal blooms and oxygen depletion. The advanced treatment at Suurupi helps mitigate these impacts by removing nitrogen and phosphorus, protecting the coastal ecosystem and supporting fisheries and recreational uses.