Mark P. Kumler, Ph.D.
Douglas M. Flewelling, Ph.D.
Excessive amounts of nutrients in a water body can create a “dead” lake. The process of eutrophication causes the lake to lose oxygen, the aquatic life die, and the health of the water is diminished both biologically and aesthetically. One group of common nutrients involved in this process are phosphate, which can enter a water body through hydrologic runoff.
Dr. Blodwyn McIntyre, an environmental science professor at the University of Redlands, researches phosphate loading in the high elevation lakes of the Sierra Nevada in central California. She needed a way to quantify the amount of phosphates being contributed to the lake as a result of hydrologic runoff as well as visualize phosphate amounts in Silver Lake and Convict Lake.
A GIS was designed to perform a multi-criteria analysis in which environmental factors were analyzed to determine their effect on phosphate loading at the watershed level. The process was automated using ArcGIS for desktop’s Model Builder and ArcScene software. The results were displayed on a close-to-reality three dimensional model.
The analysis resulted in a potential non-point source pollution index that estimates the amount of phosphates coming from different areas of the watershed during a rainfall event. The final information product was a user friendly interactive 3D web scene.
Taylor, M. S. (2014). WNAT: A Tool for Modeling Phosphate Loading from Hydrologic Runoff using Multi-Criteria Analysis and 3D GIS (Master's thesis, University of Redlands). Retrieved from https://inspire.redlands.edu/gis_gradproj/209