The use of geographical information systems in catchment hydrology modeling : a case study from the Göksu river

Abstract

During the past few decades many enhancements have been made to traditional catchment-scale hydrological modeling by the help of Geographical Information Systems (GIS); with gradual availability of such data and increased computer power, most of the recent hydrological analyses make use of GIS as the main methodological approach to catchment discretization. GIS have also frequently been used in input-output data handling for hydrological modeling purposes, derivation of flow direction-length and slope maps from Digital Elevation Models (DEMs). As a methodological protocol, this study is uniquely applicable to rainfall-runoff analysis using SWMM and ArcGIS software. Integration of data file exchange was a critical link for this study. In this case, attribute tables for soil, land-use and virtual rainfall were generated by ArcMap and analyzed to develop the parameters for the input files for SWMM. SWMM and ArcGIS were chosen because of their relative popularity with many professionals. The main aim in this study is to determine a solid information collection and implementation strategy that could make maximum use of geographical information systems, with which; data, results, images and graphs also become more understandable during and after the study overall. As noted by Intergovernmental Panel on Climate Change (IPCC, 2007), we still do not have an adequate understanding and ability to model and predict water cycle processes and the associated feedbacks. This study is just a brick in this tower of learning.