Council Directive 91/271/EEC

The Council Directive 91/271/EEC concerning urban waste-water treatment was adopted on 21 May 1991. Its objective is to protect the environment from the adverse effects of urban waste water discharges and discharges from certain industrial sectors (see Annex III of the Directive) and concerns the collection, treatment and discharge of:

  • Domestic waste water
  • Mixture of waste water
  • Waste water from certain industrial sectors (see Annex III of the Directive

This is illustrated in the figure below:

Wastewater discharge scheme according the council directive 91/271/EEC

Wastewater discharge scheme

Four main principles are laid down in the Directive:

  • Planning
  • Regulation
  • Monitoring

Information and reporting

Specifically the Directive requires:
The Collection and treatment of waste water in all agglomerations of >2000 population equivalents (p.e.);
Secondary treatment of all discharges from agglomerations of > 2000 p.e., and more advanced treatment for agglomerations >10 000 population equivalents in designated sensitive areas and their catchments;
A requirement for pre-authorisation of all discharges of urban wastewater, of discharges from the food-processing industry and of industrial discharges into urban wastewater collection systems;
Monitoring of the performance of treatment plants and receiving waters; and
Controls of sewage sludge disposal and re-use, and treated waste water re-use whenever it is appropriate.