Abstracts Geography

HMS-PrePro : a GIS preprocessing tool for extracting geospatial data and preparing HEC-HMS models

by -8825-9900

In hydrological modeling, GIS pre-processing tools use geographic data to spatially relate different datasets and simulate a series of processes that estimate hydrologic parameters. In order to derive basin parameters for HEC-HMS and other hydrologic models, a physical description of the watershed is required. Landscape information is in abundance through governmental agencies, research institutions, online searches, and data servers. Obtaining such data typically requires various sources with unique formats and resolutions. Often, the data must then be pre-processed on a local computer, which poses difficulties with user-storage requirements. The issue is no longer with data scarcity but instead with the timely acquisition and management of such information. Esri’s Living Atlas of the World was created to provide users with access to geospatial data in a cloud-based environment that may be used for common processing tasks. A tool called HMS-PrePro was developed that uses authoritative data from the Living Atlas for hydrological modeling. Specifically, HMS-PrePro is a GIS-based preprocessor that extracts data for a watershed of interest and prepares HEC-HMS model input files. Since a significant portion of HEC-HMS input data is spatially-derived, the Living Atlas is used to estimate parameters such as watershed losses or the runoff rate over a land surface. In HMS-PrePro, datasets from the Living Atlas are extracted for a watershed boundary and then spatially and topologically related using Python-programming in an ArcGIS environment. Comparison studies between HMS-PrePro and effective local models have resulted in an acceptable rainfall-runoff output for model initialization. HMS-PrePro has been shown to produce the same watershed parameters as HEC-GeoHMS, a popular GIS preprocessor from the U.S. Army Corps of Engineers. Findings from this research suggest that data services may be used in watershed modeling. Instead of representing hydrology through labor-intensive data processing, it is possible to characterize watersheds through an information-based GIS environment. Connecting data services with HEC-HMS allows modelers to continue working with familiar tools. HMS-PrePro provides a rapid operational link between raw hydrological data and end users. Advisors/Committee Members: Maidment, David R. (advisor), McKinney, Daene C (committee member).