2015 GSA Annual Meeting in Baltimore, Maryland, USA (1-4 November 2015)

Paper No. 210-96
Presentation Time: 9:00 AM-6:30 PM

TURBIDITY, TOTAL SUSPENDED SOLIDS, AND E. COLI CORRELATION ON THE LITTLE TALLAPOOSA RIVER, CARROLL COUNTY, GEORGIA


SIMPSON, John and HOLLABAUGH, Curtis L., Geosciences, University of West Georgia, Carrollton, GA 30118, jsimpson9@my.westga.edu

In the Piedmont province of Georgia the Little Tallapoosa River provides drinking water for 43,845 people in Carroll County. Long-term water sampling has been conducted by the UWG Center for Water Resources and provides key data for the Little Tallapoosa’s health. Though numerous tests are conducted both in field and in the laboratory the purpose of this research is aimed at proving a correlation first between Total Suspended Solids (TSS) and turbidity and between TSS and E. coli bacteria present in the Little Tallapoosa River. To determine the relationship between TSS and turbidity of the Little Tallapoosa River system in Carroll County, five sites on the Little Tallapoosa that are sampled 12 times a year were examined. The sampling was done from late 2003 to early 2015 at these sites. TSS measurements were developed in the lab following EPA approved methods. TSS is measured by filtering the sample water, and then calculating the change in mass for the filter. The turbidity portion was recorded in the field using a turbidimeter and a blank before each sample. Turbidity is the measure of how much transparency is lost caused by suspended particles. TSS reflects on everything suspended in the water column -- be it soil, plankton, microscopic lifeforms, or bacteria. This research showed a correlation between TSS and turbidity in most areas of the river. At site CTN-120 the R2 = .4222 and then at site CTS-70 further downstream the R2 = .831 for the TSS / turbidity relationship. This wide range of values could be caused by several factors such as rainfall, urban versus rural runoff, construction, reduced velocity, and stagnant water to name a few factors. For TSS vs E.coli the R2 values range from .7244 to .8952; indicating a significant relationship the higher the E.coli values corresponding to higher TSS values. If E. coli measurements are not available, E. coli predications based on TSS values could be used with a statistical best fit formula. TSS sampling is relatively time consuming, however it is less expensive than the analysis of E. coli. TSS data is also available within hours of sampling whereas E. coli samples require a 24 hour wait time. In larger watershed basins, automated turbidimeters have been used to record and predict E. coli levels. In this basin, turbidity did not correlate well with E. coli.