Reduser skriftstørrelsen Øk skriftstørrelsen

The National River Network Database (ELVIS)

12.05.2011 | 10:30

ELVIS is the river network database for Norway’s river system

In ELVIS all river system elements are represented by line objects connected in a logical network with a defined flow direction. The line segments in ELVIS are identified by use of the Norwegian Mapping Authority’s (Statens kartverk) digital main map series N50 Kartdata (accuracy matching map scale 1:50 000). Through lake and wide river polygons, mathematical centrelines are generated, then linked with the other river line objects to create the complete river network. Correct flow direction is defined in the dataset.

Each line segment – or water system section – is given a unique National Identification Number (strekn_nr) which is the reference number for all elements of the surface water system; streams, rivers and lakes. The ELVIS database contains information about the relevant catchment area number and lake number for each river segment.

ELVIS Database Attribute Table Content

  • National Identification Number (strekn_nr)
  • Catchment number (vassdragnr)
  • Lake number (when passing through lake)
  • River/lake/catchment area name
  • Length of segment

    The National Identification Numbers enable storage, systematic registration and retrieval of water related information and ensure correct connection with other national databases. Furthermore, they ensure that all parties refer to the same river segment(s) and are used in national and regional databases related to water use, management, environment, pressure etc.

    ELVIS is updated and maintained by NVE and available for users in the map application NVE Atlas (

    ELVIS is also available on the WMS format (Web Map Service). The list of WMS is available here, or at the National Map Portal  established by Norge digital/Norway Digital.

    Requests about the database may be sent to