Private households who are not catered to by a water supply agency get their drinking water from drilled wells or driven wells
Driven wells (ring wells)
Driven wells, or ring wells, are only a few meters deep and are lined with concrete rings. The oldest wells are lined with stones.
The water quality of shallow wells may be compromised if surface water gets in, as it brings bacteria into the well. Surface water can cause well water to become cloudy during spring and autumn. The well water often has high iron concentrations. Wells near fertilized fields or manure storage may have high concentrations of nitrate, which makes the water unsafe to drink.
Drilled wells are constructed by drilling into bedrock, sometimes as deep as 200 meters. In Pirkanmaa, risks to water quality include radon and arsenic. Individual wells can vary drastically, so the only way to know is by taking a water sample.
Water quality requirements and recommendations for private wells are ruled in the decree 401/2001 by the Ministry of Social Affairs and Health.
The structural condition of the well should be inspected annually and a water sample should be taken every three years, if no abnormalities appear in the taste, smell, or colour of the water. You can easily take the water sample yourself. Health inspectors provide guidance on well water samples and well repair. The owner of the well is responsible for paying the laboratory’s fee for testing water samples.