# Council Directive of 21 May 1991 concerning urban waste water treatment (91/271/EEC), Article 10

Extent: E+W+S+N.I.

Member States shall ensure that the urban waste water treatment plants built to comply with the requirements of Articles 4, 5, 6 and 7 are designed, constructed, operated and maintained to ensure sufficient performance under all normal local climatic conditions. When designing the plants, seasonal variations of the load shall be taken into account.

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Source: https://www.legislation.gov.uk/eudr/1991/271/article/10 (the official version)
Page: https://openlegislation.uk/eu-directive-1991-271/article-10
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.