Drinking water quality in Finland is very good: THL

Finnish drinking water is of a very good quality, according to a recent report published by the Finnish Institute for Health and Welfare (THL) on Wednesday.

Drinking water is water that is intended for household use, such as for drinking and cooking.

According to the report, the health-based requirements set for the quality of drinking water were met by 99.98 per cent of the samples in 2021. The quality requirements ensure that drinking water does not cause any health hazards to its users.

There were deviations in the health-based quality only in individual water supply areas and mainly in individual water samples. The quality of drinking water was improved to the level set in the requirements, for example, by discontinuing the use of a contaminated raw water well. Some of the quality deviations were caused by the water systems of the building.

“The quality of drinking water may change in the building’s water system, for example, if water is not used for a long time. It is then a good idea to let the water run for some time before using it again. This way, the drinking water that has not been moving in the building's pipes and inside the tap will be replaced by fresh water of a good quality,” said Outi Zacheus, Senior Planning Officer of THL.

The quality targets set for the usability of drinking water were also met well. These quality targets have not been set on health grounds, and deviations from them do not cause any health hazards to the user.

The greatest number of deviations were caused by a high iron or manganese content, an abnormal number of microbes, or coliform bacteria.

The usability of drinking water was also improved in many different ways, such as by servicing and cleaning water tanks and flushing water supply networks. The impact of the measures taken to improve the quality of drinking water was monitored by taking additional samples and conducting additional tests.

The results of THL’s drinking water report are based on the regulatory supervision of drinking water by municipal health protection authorities in 2021. The quality of drinking water was examined in the 147 largest water supply areas with a total of about 114,000 examinations. There are more than 4.6 million water users in the water supply areas.