Short answer. Swiss water suppliers are responsible for drinking-water quality and cantonal laboratories supervise them 5; we found no national list of boil-water notices, and trinkwasser.ch carries no emergency messages 1. The federal supply office (FONES) asks every household to store at least 9 litres of water per person, one six-pack of 1.5 L bottles, for three days 2. Drought warnings are issued for 38 regions 3.
How do I know if my tap water in Switzerland is unsafe?
The Federal Food Safety and Veterinary Office (FSVO, German BLV) states that water suppliers are responsible for the quality of drinking water and test it regularly, and that cantonal laboratories supervise the suppliers 5. We found no single national list of boil-water notices. The industry platform trinkwasser.ch, run by the SVGW (a trade association, not an authority), lets you search by postcode or map for your supplier's data, but publication there is voluntary for each supplier 1. The site states that it provides no real-time information or emergency messages about contaminated drinking water, and that questions about the quality data go directly to your supplier 1.
In practice: know the name of your water supplier and how it contacts residents, and follow its instructions. If you are told to boil water or not to drink it, see our guides on a boil-water notice and a do-not-drink notice. For official warnings in general, see our Switzerland alerts page.
How much water should I store in Switzerland?
FONES sets the minimum at 9 litres per person, the equivalent of one six-pack of 1.5 L bottles, for drinking and cooking over three days 2. It also states that water suppliers must restore a minimum drinking-water supply from the fourth day of an interruption 2. Our Switzerland emergency supplies page covers food and the rest of the list; how much water per person compares other agencies' figures, and water storage containers covers how to keep it.
Is Switzerland short of water?
Not on average. Using the World Resources Institute's Aqueduct 4.0 data, the median Swiss city sits in the "low" baseline water-stress category today and is still "low" in the 2050 business-as-usual projection 4. Drought risk is higher: the median city falls in the "medium" drought-risk category 4. These are medians across 1,567 cities weighted by population; individual valleys and regions differ.
Droughts are monitored nationally. The federal drought platform issues official warnings per region, based on a weekly expert assessment, using two levels of the national hazard scale 3:
| Level | What it means | What to do |
|---|---|---|
| 2 (yellow), moderate | A prolonged drought is developing; local restrictions on water use are possible | Check the situation in your region, find out about possible restrictions, use water sparingly 3 |
| 4 (red), high | Significant impacts; restrictions likely at local to regional level, bans possible | Follow the instructions and bans of local authorities on water use and forest-fire risk; use water sparingly 3 |
Level 4 is aimed at the general public: from that level, people should expect to be directly affected by restrictions set by cantons or municipalities 3. Warnings cover 38 regions, based on the federal warning regions also used for storm and flood warnings 3. See drought preparedness.
What if the water stops or a flood hits?
If the tap runs dry, start with your stored water and read no running water. After a flood, treat tap and well water with caution until your supplier says otherwise; see water after a flood and water purification. We found no federal page on private wells; if you rely on one, see private well emergency.
Your household plan can record your supplier and your stored water in one place.
Frequently asked questions
Will trinkwasser.ch tell me about a boil-water notice?
No. The site states that it offers no real-time information or emergency messages about drinking-water contamination 1. Your water supplier is responsible for water quality, under the supervision of the cantonal laboratory 5.
Is 9 litres of water per person enough in Switzerland?
FONES presents 9 litres as the amount for drinking and cooking over three days, and says suppliers must restore a minimum supply from the fourth day 2.
Who decides watering bans during a drought?
Cantons and municipalities. The federal platform warns; at level 4 it tells the public to follow local authorities' bans and restrictions on water use 3.
Where can I see the drought situation for my region?
On the federal drought platform, trockenheit.admin.ch, which publishes the situation and warnings for 38 regions 3.
Sources
- SVGW (Swiss Gas and Water Industry Association), trinkwasser.ch — Trinkwasserqualität an Ihrem Wohnort — https://www.trinkwasser.ch/ (accessed 2026-10-27)
- Bundesamt für wirtschaftliche Landesversorgung BWL — Kluger Rat – Notvorrat — https://www.bwl.admin.ch/de/kluger-rat-notvorrat (accessed 2026-10-27)
- Nationale Trockenheitsplattform (BAFU, MeteoSchweiz, swisstopo) — Trockenheitswarnungen und Verhaltensempfehlungen — https://www.trockenheit.admin.ch/de/trockenheit/trockenheitswarnungen-und-verhaltensempfehlungen (accessed 2026-10-27)
- World Resources Institute — Aqueduct 4.0 (water stress, 2050 projection, drought risk) — https://www.wri.org/aqueduct (accessed 2026-10-27)
- Bundesamt für Lebensmittelsicherheit und Veterinärwesen BLV — Trinkwasser — https://www.blv.admin.ch/de/trinkwasser (accessed 2026-10-27)
Turn this into action
Your plan for Switzerland, worked out for your household.
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Sources
- SVGW (Swiss Gas and Water Industry Association), trinkwasser.ch · Trinkwasserqualität an Ihrem Wohnort checked 2026-10-27
- Bundesamt für wirtschaftliche Landesversorgung BWL · Kluger Rat – Notvorrat checked 2026-10-27
- Nationale Trockenheitsplattform (BAFU, MeteoSchweiz, swisstopo) · Trockenheitswarnungen und Verhaltensempfehlungen checked 2026-10-27
- World Resources Institute · Aqueduct 4.0 (water stress, 2050 projection, drought risk) checked 2026-10-27
- Bundesamt für Lebensmittelsicherheit und Veterinärwesen BLV · Trinkwasser checked 2026-10-27