In Norway about 15 % of water supply is based on groundwater. This is rather low compared to many other European countries: Denmark, Austria and Iceland use groundwater for more than 95 % in their water supply. The reason for the limited use of groundwater is ready access to abundant fresh surface water in Norway. However, recently groundwater is increasingly being used in rural areas where water quality and sanitation may be of concern, and because groundwater is often more economical.
Groundwater can be extracted through drilled wells in bedrock and tube wells in unconsolidated sediments. A well drilled in bedrock must be deep enough to ensure a stable inflow of water, even during long, dry periods. Because the most common rocks in Norway are non-porous, a bore well must cross one or more water-bearing fractures in order to produce water. Groundwater from in hard rock is usually used to supply smaller freshwater facilities and homes. Tube wells, forced through soil, gravel or sand usually provide larger volumes of water than bore wells. Tube wells are fitted with customized screens which prevent sediment from entering the water in well.
Groundwater is not just for drinking - 40% of the wells drilled in Norway each year are used for the public water supply. Groundwater is also used for irrigation, in aquaculture, and increasingly for renewable energy production using heat pumps. Its heating capacity makes groundwater ideal for use as an energy source both for heating and for cooling of houses and industrial buildings.
Does a landowner have rights to the groundwater under the surface, to be used as they wish? According to Water Resources Act, the landowner owns the groundwater underneath the surface, but their access to it is limited. Regulations and licensing obligations related to use of groundwater can be found in the Water Resource Act - NVE Facts No. 6 2002 (PDF). Landowners are free to extract water for their households, including livestock and irrigation of crops. For any water withdrawal that exceeds this, the landowner must apply to NVE for a license. Withdrawing water for domestic use may also be a matter of concern if nearby waterways is affected. The rate at which groundwater is withdrawn should not be faster than the rate it is replaced.