Follow water from homes through sewers and treatment back to the river. Explore equipment, look inside tanks and discover how the processes connect to the Directive.
Physical, chemical or combined processes, such as sedimentation, remove part of the pollution. Under the Directive’s definition, BOD₅ (five-day biochemical oxygen demand) is reduced by at least 20% and suspended solids by at least 50%.
Reduces nitrogen, phosphorus or both in wastewater and limits eutrophication. It can take place in the same biological stage as secondary treatment; it does not always require a separate tank downstream.
Reduces a wide range of micropollutants, such as pharmaceutical residues and hormones. Ozonation and activated carbon illustrate these processes in the model. UV disinfection alone does not meet this definition.
An illustrative larger plant. Equipment and treatment combinations vary; flow speed and particle size are simplified.
