Total emission of an urban area considering the interaction between drainage system and treatment plant

Continuous longterm calculations of quantity and quality processes on the catchment surface, the sewerage system and the treatment plant of the City of Hildesheim have to be carried out in order to estimate the effect of the urban area on the receiving water. The calculations are performed with a pollutant-load-calculation model including a coupled hydrologic-hydrodynamic runoff-transportation module. The achievement of the developed model is shown in the example of two different subcatchments of the City of Hildesheim. With the help of this concept, it is possible to consider the existing transport, storage and treatment capacity more flexible and to find optimal rehabilitation concepts concerning the emission loads just like the resulting costs.