GIS Tools and Techniques for Analyzing and Modeling River Channel Data

Anisotropic nature of meandering river morphology poses unique challenges in analyzing and modeling river channel data using GIS. Standard GIS tools that use Cartesian (x,y) coordinates are not appropriate for dealing with river channels because of their inability to handle river anisotropy. The objectives of this paper are to highlight the importance of river anisotropy in GIS analysis, and propose techniques and tools to handle river channels in GIS. A GIS toolset called GIS River Analysis Toolkit (RAT) is developed to compute river attributes, perform spatial analysis and communicate with external hydraulic models. The basic foundation blocks of GIS-RAT are the geodatabase model which is inherited from ArcHydro, and the flow oriented coordinate system that honors river data according to the flow direction. Key functions in GIS-RAT are discussed, and presented in this paper by using data from several rivers in the United States.