HORUS: A conceptual model of pollution simulation in sewer networks

This paper presents the conceptual model for solid production and transfer in combined or separate sewerage systems called HORUS. The objective of thi s model is, taking into account the characteristics of the catchment and th e structure of the sewerage system to reproduce the hydrographs. Total Susp ended Solids (TSS) and Chemical Oxygen Demand (COD) concentration generated by any rainfall. HORUS consists of main connected modules and the retained algorithms have been chosen after using a special Testing Bench of Polluti on Modelling Algorithm in Urban Sewer System. The main modules are: a hydro logical module (linear reservoir and runoff losses), a hydraulic module (de scribed by the Muskingum model), a module for solids production and transpo rt (build-up and washoff of catchment and solid transport in sewer) and a m odule for numerical optimisation. The improvement of the HORUS model is sho wn by a comparison between simulation results versus the initials algorithm s. Simultaneous measurements of rainfall, hydraulic, TSS and COD concentrat ions on nine very different catchments and about one hundred rainfall event s allowed a large range of validation which can be considered of good quali ty. HORUS provides a satisfying fitting of the real TSS and COD pollutograp hs (flow and concentration) and this, considering the global form, maximal values and the temporal position. (C) 1999 IAWQ Published by Elsevier Scien ce Ltd. All rights reserved.