Drinking-Water Initiative: Better Water Quality in Switzerland, Higher Environmental Impacts Abroad

In Switzerland, implementing the Drinking-Water Initiative would have positive consequences for the environment, but more food would have to be imported. A life-cycle assessment study by Agroscope analyses the overall impact.

The use of pesticides and imported animal feed is viewed in an increasingly critical manner. Switzerland will therefore soon vote on two popular initiatives that aim to reduce their negative consequences. One of these is the Drinking-Water Initiative (DWI).

Two DWI measures examined

Agroscope examined the environmental impacts of two DWI measures, to wit, that only those farms which

  1. produce without pesticides, and
  2. keep only as many animals as could be fed with forage that could be produced on-farm will still be entitled to direct payments.

Comprehensive study of the environmental impacts

This study is based on the life-cycle assessment method, which quantifies all environmental impacts for the entire life cycle of a product. Both agricultural production as well as its upstream processes such as the production of fertilisers, pesticides or machinery, changes in land use and production practice within Switzerland, and the effect of changing import and export volumes were considered. Three external experts have confirmed the quality of the study in terms of international standards.

Food imports are increasing

The life-cycle assessment study is based on the same scenarios developed in an earlier Agroscope study. An important finding of this previous study was that in all scenarios, food imports would rise compared to the reference, since the implementation of the Drinking-Water Initiative would cause a fall in the domestic production of crops and animals. In the current life-cycle assessment study, the environmental consequences of these scenarios were compared with those of a reference scenario corresponding to the continuation of the current agricultural policy. For each scenario, the impacts of a ‘basket’ of agricultural products that also contained imported products were calculated. The study assumes that imports are from the same countries of origin as at present.

Swiss water bodies benefit significantly

The study concludes that implementing the DWI would reduce environmental impacts in Switzerland: Depending on the scenario, the pollution of water bodies with organic contaminants would fall by 51% to 75% compared to the reference scenario. For the remaining DWI target impacts (biodiversity, eutrophication and acidification), improvement in Switzerland compared to the reference stands at a maximum of 10%. The remaining environmental impacts also improve within this range.

Greater environmental pollution abroad

If we look at the environmental impacts of the entire basket of products, i.e. including the environmental impacts abroad caused by the increasing imports, then only the pollution of water bodies with organic contaminants shows a certain improvement. Terrestrial eutrophication and the demand for abiotic resources remain constant, and all other environmental impacts, including species loss, deforestation and water scarcity, become worse.

Stark environmental consequences of meat imports

With implementation of the DWI, the two measures – ‘forgoing pesticides’ and ‘reducing livestock numbers’ – affect the life-cycle assessment of the Swiss basket of products differently:

  • Forgoing pesticide use only affects some of the environmental impacts: organic pollutants in water bodies decrease, whilst water scarcity increases (e.g. owing to the production of plant-based foods in countries with greater water scarcity).
  • The reduction and extensification of the livestock population influences all environmental impacts, and leads to significant trade-offs: In Switzerland, ammonia pollution (acidification, terrestrial eutrophication), greenhouse-gas emissions and demand for abiotic resources all fall, but the importing of animal-based foods leads to high impacts abroad in almost all environmental areas.


  • With implementation of the Drinking-Water Initiative (DWI), the contamination of Swiss water bodies with organic pollutants would fall significantly (by 51% to 75%).
  • Other environmental impacts in Switzerland that the DWI aims to improve, such as biodiversity or nutrient enrichment in aquatic and terrestrial ecosystems, would also be positively affected, but to a less significant extent (max. 10%).
  • Looking at the entire basket of products (including imports), implementation of the DWI slightly improves the contamination of water bodies with organic pollutants; the remaining environmental impacts remain the same, or worsen (e.g. biodiversity, deforestation and water scarcity).
  • The DWI measures ‘forgoing pesticide use’ and ‘reduction of livestock numbers’ affect the environmental footprint differently. ‘Reduction of livestock numbers’ in particular leads to significant trade-offs, since rising imports of animal-based foods strongly increase the environmental impact of the Swiss basket of products abroad.
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