Well water as domestic and drinking water

In sparsely populated areas without municipal water supply, domestic water is obtained from wells. Well water is groundwater formed from rain and meltwater absorbed into the soil. As water filters through soil layers, it is purified and various substances dissolve into it. The quality of well water can also be affected by human activity near the well and the condition of the well structures. Property owners are responsible for the condition of their wells and for getting the water tested.

Well water in Western Uusimaa

In Western Uusimaa, harmful levels of radon, uranium, arsenic and fluoride can occur especially in drilled wells. Therefore, regular testing of well water is important.

Radon

Radon is an odourless, tasteless and invisible gas. Radon in domestic water increases the risk of lung cancer because exposure to radon occurs mostly through the air we breathe. Radon is released into the air during activities like showering, heating water or using washing machines.

Fluoride

A small amount of fluoride is necessary for humans to prevent tooth decay. However, excessive fluoride intake causes developmental defects in tooth enamel. Therefore, it is especially important that the drinking water of infants and pregnant women does not contain too much fluoride. High intake of fluoride may also increase the risk of hip fracture, especially in the elderly.

Water with a fluoride content exceeding 2 mg/l should not be used permanently as drinking water or for cooking.

Arsenic

Long-term use of water containing arsenic most commonly causes bladder cancer, but lung and skin cancers have also been observed. At high concentrations, arsenic has also been linked to diabetes, cardiovascular diseases, skin changes, and damage to peripheral nerves.

Uranium

Excessive intake of uranium can impair kidney function, for example. However, uranium is poorly absorbed into the body through the digestive tract and is quickly excreted in urine. Exposure to uranium through shower water is also minimal.

Information about wells (vesi.fi, in Finnish)(external link, opens in a new window)

Chemical quality of well water (Finnish Institute for Health and Welfare, in Finnish)(external link, opens in a new window)

Quality of well water (vesi.fi, in Finnish)(external link, opens in a new window)

Well water testing

The quality of well water should be analysed at least every three years. This is important, as wells can be exposed to surface and meltwaters, especially in the spring. Well water should also be analysed if:

the colour, taste or odour of the water has notably changed;
it is suspected that the well water poses a health hazard;
the well has not been used for a long time;
construction work is carried out near the well;
there are small children or pregnant women in the family.

The analysis can only be carried out in a laboratory. The analysis is subject to a fee, and the well owner is responsible for getting the water analysed and paying the related fees. You should avoid drinking suspicious well water until it has been analysed in a laboratory.

Taking water samples in Espoo and Kirkkonummi

You can pick up water sample bottles from:

Espoo’s Urban Environment Customer Service in Otaniemi at Tekniikantie 15 (2nd floor), between 8:00 and 15:30
Kirkkonummi’s municipal service point at Ervastintie 2. Check the opening hours of the service point on the Kirkkonummi municipal website (only in Finnish).(external link, opens in a new window)

You can also order or pick up sample bottles directly from laboratories. You can find information on laboratories that analyse water samples on the website of the Finnish Food Authority (in Finnish)(external link, opens in a new window).

Samples that will be analysed at Metropolilab can be dropped off at:

Espoo’s Urban Environment Customer Service on Mondays by 11:00, or
Kirkkonummi’s municipal service point on Mondays by 13:00. Samples will then be delivered to the laboratory.

Kirkkonummi’s municipal service point is closed in July. During this time, water samples from private wells can be taken either directly to Metropolilab or to Espoo’s Urban Environment Customer Service in Otaniemi at Tekniikantie 15 by 11.00 on Mondays.

Water samples can also be taken directly to a laboratory.

Interpreting the results

If your well water contains harmful substances exceeding the recommended levels, it does not automatically mean that using the water will cause health problems. The potential health risks depend on several factors, such as how the water is used, the amount of the harmful substance, and the amount of well water consumed.

If you need help interpreting your well water test results, you can contact Espoo Region Environmental Health Services by email at talousvesivalvonta@espoo.fi.

Harmful substances can be removed from well water using various technical treatment methods. Many companies offer different treatment solutions for well water. Read more about well water treatment (vesi.fi, in Finnish)(external link, opens in a new window)

Check the condition of your well

You should check the condition of your well every spring. There are several important aspects to consider when checking the condition of the well:

The well cover must be tight-fitting and intact to prevent small animals or surface or meltwater from getting inside the well. It is a good idea to have a lock on the well cover to reduce the risk of vandalism.
The external and internal structures of the well should be in good condition when checked visually, the seams should be tight, and the frost insulation should be in place.
The inside of the well should be clean, and there should be no runoff marks indicating that rain, surface or meltwater has seeped inside.
The water in the well should be clear and free of debris.

You should also inspect the surroundings of the well. Pay attention to ground depressions, which may damage the structures of the well or form pools of rain or meltwater. At the construction stage, the land around the well should be contoured so that it slopes away from the well, taking rain and meltwater with it.

Well repairs and disinfection should be carried out by trained professionals. There are several companies specialising in well maintenance and disinfection.

Well-related notifications

A written notification of a water distribution area must be submitted to Espoo Region Environmental Health Services in the following cases:

establishment of a new domestic water well shared by properties (more than 50 users or volume of supplied water at least 10 m3 per day);
well water is used in food premises or in public or commercial activities.