GIS-based approach to sewer system design

In planning and design of sewer networks, most decisions am spatially depen dent because of the right-of-way considerations and the desire to have how by gravity. The geographic information system- (GIS-) based approach takes advantage of the spatial analysis capability of GIS in combination with a s ewer design program to develop an integrated procedure for the design of se wer systems. The program that was developed uses the user specified namhole s' locations to generate the sewer network. The GIS is used to analyze the area's topography, surface features, and street network to delineate subwat ersheds, to locate pump stations, and to determine the path for the force m ain. The program was successfully demonstrated for two areas in the town of Blacksburg, Va. In comparison with a traditionally designed path for the f orce main, the developed approach results in a better design. It also was p ossible to design a complete sewer network with minimal human intervention.