The model system STOFFBILANZ ( is a complex tool for modelling water, sediment and nutrient flows in catchment areas. It serves to make contributions to water management planning and the derivation of mitigation options in order to reduce sediment and nutrient emissions into waters. STOFFBILANZ is a model developed for the mesoscale and mediates between large-scale and small-scale processes. A detailed model description is available here.

Nitrate and phosphorus pathways

Users and application areas

Within the framework of various studies funded by the Federal Government and the Länder (e.g. Saxony, Baden-Württemberg, Saxony-Anhalt, Rhineland-Palatinate, Lower Saxony), associations, dam administrations and research institutions, the modelling of soil erosion by water and of sediment, nitrogen and phosphorus inputs in river basins was carried out. In this context the model STOFFBILANZ was established and successfully applied, optimised and further developed in many areas of Central Europe and meanwhile also in Asia and Africa.

Fields of application

In Germany, STOFFBILANZ model is mainly used in connection with the implementation of the EU Water Framework Directive (WFD), the Fertiliser Ordinance and the obligations to achieve the marine protection goals. The model results for nitrogen and phosphorus inputs can be used to derive reduction requirements for achieving environmental quality objectives and meeting environmental quality standards. Scenario calculations are used to assess the potential for reducing substance inputs. The focus here is on measures in the field of urban water management and agri-environmental measures in agriculture.

What can STOFFBILANZ do?

Modelling with STOFFBILANZ includes both Soil erosion by water and sediment, nitrogen and phosphorus inputsthe main sources and paths of input are identified and calculated for each specific natural area and use. The results represent spatially differentiated orders of magnitude of substance inputs.

As a balance sheet model, STOFFBILANZ basically allows statements on "steady-state" conditions for long-term observation periods. However, the progressive development of the model and the coupling with other process-oriented models (water balance - KLIWES and humus balance - CCB) has now made it possible to make calculations in annual steps. Depending on the data situation and requirements in the project, day-based approaches (USLEM, FAO evapotranspiration, surface runoff, ...) can also be used or integrated.

The improvement of the data situation with regard to digital elevation models and precipitation data, as well as the rapid developments in high performance computing, now allow us to work with very small raster resolutions. At the federal state level, modelling has already been carried out with 1m resolution and nationwide with 10m resolution.

The model STOFFBILANZ is designed in such a way that water, nitrogen and phosphorus budgets can be comprehensively calculated with varying data. Since the system is modular, individual approaches or even complete modules (e.g. groundwater path) can be replaced by coupling with other models (MODFLOW). On the other hand, STOFFBILANZ can only calculate individual modules (e.g. soil erosion) for model networks. Our long-term project experience has shown that cooperation and exchange with other modelling groups have a positive effect on the project results.


Important milestones in model development are:

2019Increase of the raster resolution for modeling and visualization in the STOFFBILANZ-Viewer up to 10m x 10m (Germany)
2019Integration of a binary data storage in raster format hdf5 (Hierarchical Data Format) as a basis for modeling and visualization.
2019Update of the viewer interface (front-end) to improve the user logic and simplify operation, making "state of the art" design adjustments
2015The software integration of a matrix computer now allows the processing of very large amounts of data in modeling with STOFFBILANZ.
2013Provision of the web-based portal STOFFBILANZ viewer for the BMBF-funded project "SPACES - SGD" (South Africa)
2012Technological redesign of the web-based STOFFBILANZ viewer.
2012Realisation of a day-based resolution of the modelling of water flows, soil erosion, sediment input and particle-bound P-input within the BMBF-funded project "Development and implementation of a scientifically based management system for the reduction of diffuse substance inputs into the Miyun drinking water reservoir near Beijing" (FKZ 02WM1049)
2011Integration of potentials of measures to reduce soil erosion and material input for the whole of Saxony on behalf of the LfULG
2010In the research project "Biomass" of the LfULG Saxony the model is used to investigate the effects of an increasing cultivation of renewable raw materials on the water balance and water protection based on scenarios.
2009The retention for N is determined by taking into account the N uptake rate from the sediment and the residence time of the water (Nutrient Spiralling concept). Retention in still waters / dams is done separately.
2009The long-term average annual amount of P (retention) retained in the inundation area of watercourses is calculated from the amount of sediment deposited and the specific particle-bound P concentration in the sediment.
2009Consideration of groundwater residence times in unconsolidated rock by modelling the distance velocities and flow paths in the upper aquifer using a multiple-flow approach.
2009Area-wide application and further development of the model approach STOFFBILANZ_Logar in the Upper Rhine Graben within the framework of the EU project "LOGAR" (responsible LUBW Karlsruhe, LTZ Augustenberg, Region Alsace, Agence de l'eau Rhin-Meuse, DIREN Alsace, BRGM)
2008Activation of the WebGIS based STOFFBILANZ viewer.
2008Mapping of dissolved N-loads with improved inclusion of mobilisation and immobilisation.
2007Initiation of the research project "Nährstoffatlas Sachsen" on behalf of the LfULG.
2007Development of the model "STOFFBILANZ_BW" modified for Baden-Württemberg conditions to model the N inputs into the endangered groundwater bodies of BW in the context of the implementation of the EU Water Framework Directive (WFD) (in cooperation with LTZ Augustenberg)
2006Further development of the particle-bound input path by including the probability of connection of erosive areas to the river network (DFG project GR 1432/5)
2006Modelling with STOFFBILANZ in the EU project "MoNit" to quantify nitrate inputs in the Upper Rhine Graben area as a partial model in a nested approach