Groundwater level situation

There are no active bulletins on the groundwater level situation right now.

Why is groundwater important?

After glaciers, groundwaters make up the second largest fresh water reserve on the Earth. Compared to our population, we have plenty of high-quality and accessible groundwater in Finland, and around 65% of domestic water supplied by water utilities in this country is groundwater.

What is actually groundwater?

Groundwater refers to all water under the ground surface that fills open spaces in the soil and bedrock fractures. Groundwater is formed when rainwater, water from snowmelt or surface water infiltrates into soil layers or flows into cracks in the bedrock. Impurities are removed from groundwater as it is filtered through soil layers, making it ideal as a source of drinking water. Some of our tap water comes from artificially recharged groundwater deposits, where surface water has been infiltrated into the soil. While the groundwater reserves in Finland recharge rapidly, there are great variations in the recharge rate globally.

Where can groundwater be found?

Groundwater occurs everywhere but particularly large volumes are formed in areas with sand and gravel deposits ideal for the infiltration of water. Areas with a rich supply of groundwater are called groundwater areas. Groundwater levels are affected by geographical location, soil types, seasons, weather conditions and human actions. The groundwater surface is usually found at a depth of two to five metres below the ground level, and considerably deeper at the centre of sand and gravel deposits. If you have a well, you can see the groundwater level by looking into it. A spring is an outlet where groundwater bubbles out of the ground.

Groundwater and the seasons

Groundwater levels fluctuate naturally as seasons come and go. As the lengths of the seasons vary in different parts of the country, so do fluctuations in groundwater levels. The volume of groundwater decreases in winter because precipitation mainly comes as snow and soil frost prevents the infiltration of water into the soil. Groundwaters are typically at their lowest level in late summer as plants use up water and it evaporates in large quantities throughout the summer, and there may also be long periods of drought. The largest quantities of new groundwater are formed during spring snowmelt and autumn rains.

Fun facts about groundwater