In Norway about 15 % of water supply is based on groundwater. This is rather low compared with many other European countries, such as Denmark, Austria and Iceland, which 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 because of reasons related to water quality and hygiene, and because water supply based on groundwater is often more economical.
Groundwater can be extracted through drilled wells in bedrock and tube wells in unconsolidated sediments. Every year about forty companies drill an estimated 5000 new wells in Norway, but only about 40 % of these wells are used for water supply. The remaining wells are used in energy production. Alternative sources of groundwater for drinking water are dug wells and natural springs.
Well drilling in unconsolidated sediments. Photo: Ø. Jæger, NGU
In Norway, the largest water works are based on groundwater from unconsolidated sediments, while groundwater in bedrock is normally used in small water works and for single dwellings or cabins. When considering having a well drilled, there are several aspects one has to be aware of. NGU has therefore included a specific menu-entry on drilling wells on the website Groundwater in Norway.
Rock surface with iron-rich coating. Photo: J. Cramer, NGUIn addition to water supply, groundwater is used in irrigation, production of mineral water, aqua-culture, and for the production of energy.
Groundwater has a good heat capacity and can therefore be employed as a source of energy when using heat pumps for either heating or cooling.
One requirement with energy extraction is a good chemical quality of the groundwater being used, in order to prevent problems with chemical precipitation of, for instance, carbonate- and iron minerals.