By 2035, urban wastewater will undergo secondary treatment...

By 2035, urban wastewater will undergo secondary treatment (i.e., the removal of biodegradable organic matter) before it is discharged into the environment, in all agglomerations of the size of 1,000 population equivalent (p.e., standard measuring unit describing the average pollution released by one person per day) or more. By 2039, tertiary treatment (i.e. the removal of nitrogen and phosphorus) will be applied in all wastewater treatment plants covering 150,000 p.e. and above, and by 2045 in those covering 10.000 p.e. and above. An additional treatment removing a broad spectrum of micro-pollutants ('quaternary treatment') will be mandatory for all plants over 150,000 p.e. (and over 10,000 p.e. based on a risk assessment) by 2045.