Water Hardness in Vienna

The degree of water hardness correlates with the minerals absorbed by water from the soil. The Law on Detergents and Cleaning Products distinguishes between three levels of water hardness:

• I: 0 to 8,4 °dH (German hardness degree)
• II: 8,4 to 14 °dH (German hardness degree)
• III: in excess of 14 °dH (German hardness degree)

The dosage of detergents and anti-chalk agents (softeners) depends on these levels of hardness. Dishwashers should be set according to the locally prevailing level of hardness (see instruction manual).

In Vienna, water hardness levels are between 6 and 11 German hardness degrees – this range is also referred to as "soft water". In exceptional cases, water hardness can rise to 16 degrees in the 2nd, 3rd, 11th, 21st and 22nd municipal districts. For water hardness settings of domestic electric appliances, the Vienna Water generally recommend a level of less than/equal to 10 German hardness degrees, corresponding to hardness level 1 under the Law on Detergents and Cleaning Products.