Water hardness in Brno by neighbourhood
Water hardness decides how much limescale builds up in the kettle, how much detergent you need and how to set the dishwasher. In Brno it differs by neighbourhood and even by street. Where the water is softer, where hard and what to do about it.
What water hardness is
Water hardness says how much dissolved calcium and magnesium the water contains. It is measured in millimoles per litre (mmol/l), but appliances are mostly set in German degrees (°dH). Detergent packs divide water into three grades: soft below 1.5 mmol/l, medium from 1.5 to 2.5 mmol/l and hard above 2.5 mmol/l. Hard water is not bad for your health, calcium and magnesium are actually good for you; it is mainly appliances that suffer.
How Brno compares
Brno’s water network is fed from more than one source, so the hardness differs by neighbourhood and by street. We compare the hardness for 36 neighbourhoods based on water analyses at their addresses. The softest water is in Kohoutovice (2.01 mmol/l), Líšeň (2.07 mmol/l) and Horní Heršpice (2.21 mmol/l), the hardest in Obřany (2.95 mmol/l), Lesná (2.92 mmol/l) and Soběšice (2.89 mmol/l). The middle neighbourhood has 2.62 mmol/l.
Water hardness in Brno: where the softest water flows
- 2.01 mmol/l Kohoutovice Brno-Kohoutovice
- 2.07 mmol/l Líšeň Brno-Líšeň
- 2.21 mmol/l Horní Heršpice Brno-jih
- 2.23 mmol/l Žebětín Brno-Žebětín
- 2.33 mmol/l Bystrc Brno-Bystrc
- 2.35 mmol/l Slatina Brno-Slatina
- 2.51 mmol/l Řečkovice Brno-Řečkovice a Mokrá Hora
- 2.52 mmol/l Stránice Brno-střed
- 2.61 mmol/l Nový Lískovec Brno-Nový Lískovec
- 2.62 mmol/l Chrlice Brno-Chrlice
What to set on your appliances
- Dishwasher: set the water hardness for your neighbourhood (in °dH, 1 mmol/l ≈ 5.6 °dH) and top up the regeneration salt. With softer water it needs less.
- Washing machine: choose the detergent dose by the hardness on the pack. Soft water needs a smaller dose, hard water a bigger one.
- Kettle and coffee machine: with hard water limescale builds up faster, so descale more often. Some coffee machines have a hardness setting just like a dishwasher.
- Boiler and water heater: hard water scales up the heating element, so regular maintenance pays off.
The hardness at a specific address may differ from the neighbourhood’s, depending on which part of the network the building is supplied from. Check an address in Brno shows the water hardness at your address.
Frequently asked questions
Where is the softest water in Brno?
According to water analyses, the softest tap water is in Kohoutovice (2.01 mmol/l), Líšeň (2.07 mmol/l) and Horní Heršpice (2.21 mmol/l).
Where is the hardest water in Brno?
The hardest water is in Obřany (2.95 mmol/l), Lesná (2.92 mmol/l) and Soběšice (2.89 mmol/l). In half of Brno’s neighbourhoods the water is harder than 2.62 mmol/l.
How do I convert mmol/l to °dH?
1 mmol/l is roughly 5.6 German degrees (°dH). Water with a hardness of 2 mmol/l is therefore about 11 °dH. Most dishwashers and coffee machines are set in °dH.