Abstract - An Evaluation of Using ArcInfo to Derive Basin Physiographic Parameters from DEMs

Track: Water Resources

Xinhao Wang
University of Cincinnati

Cincinnati, OH 45221-0016

Telephone: 513-556-0497
Fax: 513-556-1274
E-mail: xinhao.wang@uc.edu

Zhi-Yong Yin

An Evaluation of Using ArcInfo to Derive Basin Physiographic Parameters from DEMs

Characteristics of drainage networks and drainage basin physiographic parameters have been used widely in hydrologic calculation and modeling. Automated generation of drainage networks has become increasingly popular with the use of GIS and availability of digital elevation models (DEMs). This study presents an effort to explore the capability of ArcInfo in generation of drainage network and various drainage basin physiographic parameters. About twenty basins ranging from 400 km2 to 1,000 km2 in West Virginia, a geologically complex region, were included in this study. It was assumed that the generated networks based on the 1:24,000 scale DEMs can fully represent the network characteristics. This assumption was tested by various measures of geometric and topological integrity with the drainage networks on the U.S. Geological Survey 1:100,000 scale digital line graph (DLG) files. Then the networks and basin parameters based on the1:250,000 scale DEMs were compared with the 1:24,000 scale networks and basins. Basin parameters commonly used in hydrology and geomorphology were examined including drainage density, stream frequency, mainstream length, relief ratios, ruggedness number, and shape measurements. The errors and the sensitivity of these parameters to DEM scales were evaluated in relation to basin size, complexity of the networks, geology, and topography. The purpose of this study is to evaluate the feasibility of using 1:250,000 scale DEMs for small or medium sized basins. Although 1:24,000 scale DEMs should render better results than the 1:250,000 scale DEMs, the use of the latter usually takes less resources and processing time. In addition, a complete coverage of the 1:250,000 scale DEMs for the United States is available on-line free of charge. It is recognized that the DLG data do not include true first-order streams if they do not have stream flow. However, it is our intention to focus on these streams represented on the DLGs because they have well defined drainage basins and valleys. As these streams at least have ephemeral flows, they are important in water resources planning and management.