For large parts of the Ruhr area, detailed digital land use data is available from the Ruhr Regional Association (RVR) as a so-called land use type catalogue of the land use map. This land use catalogue can be converted into the land use codes NSFN required for SPRING, for the groundwater recharge calculation according to Schroeder and Wyrwich, or NMFN for the groundwater recharge calculation according to Messer. For this purpose, the RVR code must be provided via the element attribute KVRN.

Note: It should be expressly pointed out that the transformation between the individual utilisation classifications listed here is based on empirical values from which it may be necessary to deviate in individual cases. A check for plausible groundwater recharge rates with the aid of a topographical map matching the RVR code is therefore recommended.

RVR code with land utilisation according to Schroeder and Wyrwich