Drought and drinking water in Switzerland – ensuring quality, recognising risks

Periods of drought are becoming more frequent in Switzerland and are creating new challenges for households, municipalities and water suppliers. Many people are looking for reliable information about drinking water during drought, possible quality problems and specific protective measures. This landing page explains in simple terms how drought can affect the drinking water supply, when it makes sense to have drinking water analysed and how drinking water contamination during drought can be detected. Official Swiss sources are also included to ensure that the information remains technically accurate and up to date.

Why drought is relevant to drinking water in Switzerland

Climate change and longer periods of drought

• Less precipitation during certain seasons
• Higher evaporation due to rising temperatures
• Falling water levels in springs, streams and groundwater

According to the Federal Office for the Environment (FOEN), climate change is increasingly affecting water availability on a regional and seasonal basis. Smaller water supplies in particular can be sensitive to prolonged periods of drought.

Source: FOEN – Water and climate change

What does this mean for households?

• Pressure fluctuations in the water network
• Local appeals to conserve water
• Greater attention to water quality

Drinking water during drought generally remains safe as long as the water supply is properly monitored. Nevertheless, consumers should pay attention to official notices from their municipality.

Difference between water shortage and a quality problem

This is often where concerns about drinking water contamination during drought arise, although contamination does not occur automatically.

How drought can affect drinking water quality

Concentration of substances in the water

When water levels are lower, certain substances may become more concentrated, including:

• Minerals
• Nitrate
• Pesticide residues

This does not automatically mean there is a health risk, but it may be a reason to have your drinking water analysed.

Risk of drinking water contamination during drought

Possible causes:

• Surface water can enter springs more easily
• Cracks in the ground alter water flow paths
• Stagnation in rarely used pipes

Source: Swiss Gas and Water Industry Association (SVGW)

How can possible problems be recognised?

Look out for:

• unusual odour
• cloudiness
• discolouration
• metallic or earthy taste

If you notice such changes, we can carry out a detailed analysis of your drinking water quality in our accredited laboratory.

How to protect drinking water during drought

For private households

• Use water sparingly
• Flush pipes after a prolonged absence
• Maintain household water installations

For owners of wells and springs

Particular care is required here. Private water supplies should be checked regularly, as drinking water during drought can fluctuate more in private springs than in public water networks.

Recommended:

• Visual inspection of the spring
• Protection against surface water
• Microbiological testing

When should drinking water be analysed?

An analysis is useful in the following situations:

• when using a spring for the first time
• after a prolonged period of drought
• if there is an unusual taste or odour
• after flooding following a drought

Having drinking water analysed provides clarity about germs, nitrate and other relevant parameters.

Source: Federal Food Safety and Veterinary Office (FSVO)

What to do if drinking water contamination is suspected during drought?

Immediate measures

1. Do not drink the water without boiling it
2. Contact the municipality or water supplier
3. Follow official instructions

Boiling water – when does it help?

Boiling reduces many microbiological risks but does not remove dissolved chemical substances such as nitrate or pesticide residues.

Professional testing

If drinking water contamination during drought is suspected, the water should be professionally sampled. Sterile sampling is important to ensure meaningful results.

• Guide to water analysis
• Cost of drinking water testing in Switzerland
• Check household installations and water hygiene

How municipalities and water suppliers safeguard the water supply

Monitoring water quality

Public water suppliers carry out regular checks, including:

• microbiological tests
• chemical analyses
• water network monitoring

As a result, drinking water during drought remains of high quality in most Swiss municipalities.

Technical measures

• Interconnected networks between municipalities
• Additional storage facilities
• Alternative water sources
• Leakage control

Why transparency is important

Water suppliers frequently publish information about:

• water hardness
• origin of the water
• analysis results
• current notices

Anyone who wants to have their drinking water analysed can use this data for comparison.

Source: SVGW and municipal water suppliers

Conclusion – prevention provides reassurance

Periods of drought are expected to become more frequent in Switzerland. For households, this means above all: staying informed, using water sparingly and having drinking water analysed if anything appears unusual. Drinking water contamination during drought is possible, but can usually be managed effectively through monitoring, maintenance and rapid action. Anyone who follows official information from their municipality, FOEN, FSVO and SVGW can continue to use drinking water during drought safely.