Spectral Analysis of Total Coliform in a Stream in East Tennessee

Improved understanding of bacterial behavior in watersheds is necessary in order to develop management strategies for mitigation of pathogen-impaired water quality. Bacterial occurrence and persistence in streams have been demonstrated to be linked to certain hydrologic processes. The hydrologic processes may involve interactions or storage in surface or sub-surface reservoirs. Spectral analyses may provide some insights into the behavior of bacterial loading and interface with certain hydrologic reservoirs. Spectral analysis of daily total coliform data for the Little River, in East Tennessee from October 1, 2000 to December 31, 2005 was used in this case study to elucidate behavior characteristics. The objective of the study was to analyze the total coliform concentration data to determine whether this indicator demonstrates any long-term or short-term persistence and temporal scaling using spectral analysis. The pathogen indicator concentration showed short-term as well as long-term persistence ranging from about 14 weeks to approximately one year. It is speculated that hydrologic influences (surface and subsurface flow) are responsible for short-term and long-term persistence.