Water quality

Did you know that the domestic water we deliver fulfils all of the quality requirements and recommendations issued by the Ministry of Social Affairs and Health with ease? The water flowing from your tap is artificial groundwater produced at Virttaankangas.

Quality of tap water in Turku in 2021

Quality of tap water in Turku in 2021
General quality measures: unit average
Temperature °C 10,6
pH 8,6
Electrical conductivity µS/cm 140
Color mg Pt/l <1
Opacity FNU <0,1
Odor no odor
Taste no taste
Free chlorine mg/l 0,02
Total chlorine mg/l 0,21
Microbiological quality:
Coliform bacteria pmy/100 ml 0
Echerichia coli pmy/100 ml 0
Number of colonies (22 °C) pmy/ml 0
Metals and semi-metals:
Aluminium (Al) µg/l 16
Manganese (Mn) µg/l <1
Iron (Fe) µg/l 12
TOC (total organic carbon) mg/l 1,7

The quality of tap water in Turku is excellent

The quality of our domestic water remains very consistent all year round. The water in the water supply network is comfortably cool even in the summer. This means that tap water can be used for drinking, household water and washing without property-specific filtering or other treatment or a softener.



We monitor the water quality regularly in accordance with the health inspector’s approval and the monitoring study program that meets the requirements of the Domestic Water Ordinance. We send the water samples according to the program for analysis to the laboratory of Lounais-Suomen vesi- ja ympäristötutkimus Oy, which is a testing laboratory accredited by the FINAS accreditation service (T101). Also voluntarily, we observe the quality of water ourselves and participate in research projects in cooperation with other operators in the field.


Added chlorine

We want drinking water to remain fresh everywhere in Turku’s water supply network. Because of this, a small amount of chlorine has been added to the water in the form of bound chlorine, i.e. chloramine. The concentration of chloramine is affected by the temperature of the water and the length of time in the network. Some people may detect the taste or smell of chloramine in their drinking water. If the smell or taste bothers you, store the drinking water for a while in a water jug, so that the chlorine can evaporate from the water.


Water hardness

In Turku the tap water is very soft, meaning the water’s lime content is low. This means that even a small amount of detergent is enough when using a washing machine. Using too much detergent does not guarantee a cleaner end result – on the contrary – so check the correct amount of detergent according to the hardness of the water on the detergent package. No water softener or softening salt is needed.

The pH of the water is about 8.6, i.e. it is slightly alkaline, which prevents corrosion of piping materials. The pH of the water rises to this level naturally in the form of calcite from the Virttaanharju soil, so no additional chemicals are used to raise the pH.


Problems with water quality?

If you notice disturbances in the water quality, please let us know. See Turun Vesihuolto’s contact information for reporting water quality problems here.

Frequently asked questions about the quality of tap water

How hard is tap water in Turku and what is the pH of it?
Expressed with the German hardness units shown on detergent packages, the hardness of Turku tap water is 2.8 °dH (very soft). Hardness can also be expressed in mmol/l, in which case the hardness is 0.5.

The pH of Turku's tap water is 8.5–8.9, i.e. the water is alkaline.
Can warm water be used for cooking?
Warm water is not classified as domestic water and there are no quality requirements or recommendations for it. Warm water can be clearly inferior in quality to cold water, because metals from house pipes and heat exchangers can dissolve in it. It may contain too many microbes. If the water temperature is not high enough, harmful bacteria can also grow in warm water. The suitable temperature for warm water is 55–60 °C.
Why does the water sometimes look cloudy?
Turbidity is usually caused by air bubbles in the water. The phenomenon is harmless and the water becomes clear quite quickly when left standing. Turbidity almost always occurs in hot water. The air escapes upwards, making the water clear from the bottom up. If the turbidity sinks to the bottom, there is another problem.
Why does water sometimes look rusty / yellow / brown?
The reason is usually the loosening of deposits (iron and manganese) from either the public or the property's own water supply network. Detachment is most often caused by the fact that the direction of water flow has temporarily changed due to network repair or alteration work. This kind of water is usually not dangerous to health, but it is still worth avoiding drinking the water until the harm goes away by running the water from the tap. However, the water may stain laundry and water fixtures. If the water does not become normal after running the water for a reasonable amount of time, contact the water company.
Why does water look green?
If you notice a green color in the water coming from the tap, the reason may be the property's heat exchanger is broken. Green dye has been added to the district heating water as a marker. Repairing or replacing the heat exchanger is the responsibility of the property owner.
Does Turun Vesihuolto investigate the quality of well water?
The water utility only examines the quality of the water it distributes.