و تحليل هيدروليكي در محاسبه نشت شبكه هاي توزيع آب شهري GIS كاربرد مدل تلفيقي

APPLICATION OF COMBINED GIS AND HYDRAULIC SIMULATION MODELS ON LEAKAGE CALCULATION IN WATER DISTRIBUTION NETWORKS

Calculation of leakage and determination of leak location are very important for optimum management of water distribution systems. The hydraulic parameters such as pressure which are effective on leakage and are calculated by hydraulic models such as EPANET, can be stored and analyzed in a geospatial information system (GIS) model. Combination of these two models for leakage calculation is investigated in this research. In this paper the spatial data of water distribution networks is produced by AutoCAD and Arc/Info and the attribute data are added to the GIS model using Arc View. By developing two interface subroutines, the ArcView and EPANET models are combined. Then, the attribute data related to every operational situations of network are extracted from GIS and exported to the EPANET. After hydraulic simulation, the output data are imported to the GIS model to be viewed and analyzed. Applying the FAVAD concept and leakage-pressure relationship, values of leakage for the entire network and every pipe are calculated by the combined model in a discrete metered area (DMA) in the North of Iran. Based on the results of these calculations, the suspected pipes with different priorities for leak detection are identified.