How is the Water Supply in the Canton of Zurich Ensured?
Forty percent of the canton of Zurich is supplied with water from Lake Zurich. The region has a rich groundwater reservoir, so there are hardly any shortages in the drinking water supply of the area. Furthermore, the municipal infrastructures are well interconnected, so that in the event of regional shortages, supra-regional suppliers can step in. 95 percent of the population is connected to the water supply. The water supply in the Zurich region has several pillars. If one fails, another takes over. The pipeline system is of high quality and is constantly maintained, so it is stable and intact over long distances.
Should you have any questions about the supply, the Office for Waste, Water, Energy, and Air, Water Protection Department in Zurich is at your disposal.
This is how the water quality is tested in the canton of Zurich
The Health Directorate is responsible for testing the water in the canton of Zurich. The laboratory examines the origin and changes of the cantonal water. The chemical analysis provides information on the contamination with foreign substances. These can include heavy metals and other corrosion parameters, organic trace substances, or nitrates. Routine checks are carried out on water hardness and the nitrate, sulfate, or chloride content. The focus is on groundwater sources and lake water plants, which are tested for organic residues (pesticides) or heavy metals.
The health of the population in the canton is paramount. Therefore, there is close cooperation with the Water Protection Laboratory of the AWEL of the Building Department. In addition, the Cantonal Laboratory Zurich is also responsible for the quality of the water in the baths. Only through regular testing of the water in the canton of Zurich can good water quality be ensured. The AWEL, Water Protection Department, Surface Water Protection Section is responsible for the water quality of the region's lakes. These include
• Lake Hüttner,
• Lake Zurich,
• Lake Greifen,
• Lake Türler, as well as six selected small lakes.
The water quality in the canton of Zurich is checked every two years on a monthly basis. Compliance with quality criteria according to the Water Protection Ordinance (GSchV) is monitored.
What is the water hardness of drinking water in the canton of Zurich?
Water hardness affects the taste of water. In addition, high hardness levels can lead to deposits in household installations, which influence the amount of cleaning agents needed. The decisive factor is the amount of dissolved magnesium and calcium ions.
In the Swiss Midlands, the water is very hard. In Ticino, it is very soft. In the canton of Zurich, depending on the municipality and area, the hardness ranges from 14 to 18 °fH. In Rümlang, it can even reach a hardness of 41 °fH. In the municipality of Volken, the value ranges from 43 to 46 °fH. In Zumikon, however, the hardness ranges between 15 and 16 °fH. This municipality thus has the softest water in the region.
Are there any challenges regarding the water supply?
Generally, there should be no concerns about drinking and using tap water in Switzerland. However, this requires good maintenance of household plumbing systems.
As more and more fertilizers are being used in recent years, which also seep into the groundwater, wastewater treatment plants in Switzerland are being upgraded with special treatment stages. Swiss citizens can always get detailed information about the quality of their water on the website of the Swiss Gas and Water Industry Association (SVGW) or request a water analysis for the canton of Zurich.