GIS-Based Analysis of Development Options from a Hydrology Perspective

This paper summarizes research that investigated a range of suburban development alternatives from an urban hydrology perspective. Increasingly sustainable urban fringe design is characterized in this work by a mix of single family dwellings, semidetached dwellings, townhouses and apartments, a gridiron street pattern, smaller lot sizes, narrower streets, and significant open space. An analysis of a number of design scenarios based on the above characteristics was conducted for a representative urban fringe development application, with the aid of a storm water runoff simulation model (QUALHYMO) and geographical information systems software. Geographical information systems played an indispensable role in forming a connecting link between the spatial data and the simulation model, performing such tasks as watershed delineation, hydrologic parameter determination, location of developable areas, and presentation of design scenario applications. The rainfall and runoff model was used to simulate the peak flow and total runoff volume of a regional storm under current and future land use conditions. The results show that increasingly sustainable designs with smaller total development areas can effectively reduce peak flows and total runoff volumes when compared with less sustainable designs. The results of this research will be of interest to municipal engineers and local decision makers who are considering the range of possible effects of development proposals on their communities.