Waters Protection Act (WPA)
English is not an official language of the Swiss Confederation. This translation is provided for information purposes only and has no legal force.
Art. 1 Purpose
The purpose of this Act is to protect waters against harmful effects. In particular it aims: a. to preserve the health of people, animals and plants; b. to guarantee the supply and economic use of drinking water and water required for other purposes; c. to preserve the natural habitats of indigenous fauna and flora; d. to preserve waters suitable as a habitat for fish; e. to preserve waters as an element of the landscape; f. to ensure the irrigation of agricultural land; g. to permit the use of waters for leisure purposes; h. to ensure the natural functioning of the hydrological cycle.
Art. 2 Scope of application
This Act applies to all surface and underground waters.
Art. 3 Duty of care
Everyone is required to take all the care due in the circumstances to avoid any harmful effects to waters.
Art. 3a Polluter pays principle
Anyone who causes measures to be taken under this Act must bear the costs.
Art. 3a — Inserted by No I of the FA of 20 June 1997, in force since 1 Nov. 1997 (AS 1997 2243; BBl 1996 IV 1217).
Art. 4 Definitions
In this Act: a. surface waters means water bodies and their beds including the bottoms and banks, together with the fauna and flora living there; b. underground waters means groundwater (including spring water), aquifer, lower and upper confining beds; c. detrimental effects means pollution and any other operation which harms the character or function of a water; d. pollution means any detrimental physical, chemical or biological change in the nature of water; e. wastewater means water which has been altered by domestic, industrial, commercial, agricultural or other uses, as well as that which flows with such water in sewers, and precipitation water flowing off built-up or sealed area; f. polluted wastewater means wastewater which may pollute waters into which it flows; g. farm manure means liquid manure, stable manure stemming from animal husbandry as well as liquids emitted by fodder silo; h. flow rate Q347 means the flow rate which, averaged over ten years, is reached or exceeded on
let. m — Inserted by No I of the FA of 11 Dec. 2009 (Restoration), in force since 1 Jan. 2011 (AS 2010 4285; BBl 2008 8043 8079). let. n — Inserted by Annex No 4 of the FA of 15 March 2024, in force since 1 Aug. 2025 (AS 2025 430; BBl 2023 858).
Art. 5 Exemptions for reasons of national defence or emergencies
If required in the interests of national defence or in the event of emergencies, the Federal Council may, by ordinance, provide for exemptions from the provisions of this Act.