Water Quality Estimation from Regional Characteristics Using GIS

Author: Jeffery S. Horsburgh
Organization: Utah State University

4110 Old Main Hill
Logan, UT 84322-4110
USA

Phone: (435) 797-7369
Fax: (435) 797-1185
jeff.horsburgh@usu.edu

Readily available GIS data coverages and ArcView GIS were used to explore the possible relationships between water quality in streams and the regional characteristics of the streams' upstream contributing area. This study evaluated the relationships between total phosphorous measurements and the upstream distribution of land use, elevation, and total contributing area. Simple regressions on the data extracted using ArcView GIS were shown to explain a very significant portion of the variation in measurements of total phosphorous in the streams. Study results support the use of regional analysis for prediction of water quality in many applications including development of total maximum daily loads.