Water is one of our most important sources of nutrition. Most of the drinking water in Sweden consists of groundwater. It is therefore necessary to map our groundwater resources, i.e. their locations, the threats to which they are exposed, the possibility of protecting them, their capacity etc.
SGU’s groundwater mapping is an element of this work, and we provide documentation both for private water supplies and public drinking water planning programmes. Mapping is also important for the planning of land use, for instance the location of new roads, industries, and landfill sites etc., as well as for environmental monitoring in Sweden. The information is used by local authorities, county councils, public authorities, companies, and private individuals.
The main focus of mapping activities in this field is on measurements carried out with the help of seismic tools, georadar and by drilling. Seismic tools and georadar are both methods that make it possible to interpret conditions deep in the ground with the help of sound waves and electromagnetic waves. We also carry out extensive field work, measuring the water level in wells, observation tubes and springs. In the case of springs, the flow is recorded too.
The level of detail and the content of the mapping is adapted to different user groups and purposes. At present, groundwater mapping is mainly carried out at local authority level (scale: 1:50,000). It is done in periurban regions. Within the framework of the national environmental objectives programme, mapping of groundwater resources concentrates on large groundwater resources in other areas and in areas where groundwater is scarce. The local authority area groundwater maps are published on CD-ROM or can be ordered as plotted copies from SGU.