An integrated public information system for geology, groundwater and drinking water in Denmark

Denmark has a long tradition for having central geological databases, including a systematic collection and storage of geological and hydrological information from all surficial boreholes which was initiated in 1926. Since the mid-1970s such data have been stored digitally. A large variety of users access a central Danish, geological database: the public, for information about their local drinking water quality, environmental employees in municipalities, regions and the state for using, entering and updating data as well as consultants and drilling companies working for public administration and local water works. The local Danish administrative system previously consisted of 14 counties and 248 municipalities. The counties were responsible for groundwater mapping, drinking water management and activities concerning contaminated soil, as well as for harmonisation and transfer of data to the central database. With effect from 1 January 2007, this administrative system was replaced by five regions, seven environmental centres and 98 municipalities, which required major changes in the administrative handling of borehole data at the local and regional levels. For this, a public and shared central database was established and a countrywide harmonisation of data, transfer and storage was initiated and all geological, groundwater and drinking water data were transferred to this central database at Geological Survey of Denmark and Greenland (GEUS). In an updated database system, public authorities were set up to access the central database to store their relevant borehole data and almost all data were made publicly available. The database is maintained by GEUS. It is directly connected to other public databases at GEUS including the shallow geophysical database GERDA, where e.g. borehole loggings are stored, and to the Model Database where simple geological models are stored (Fig. 1). An integrated public information system for geology, groundwater and drinking water in Denmark