Comparative Baseflow Hydrochemistry of Various Septic System Density Groups within the Yellow River Watershed, Gwinnett County, Georgia

Baseflow water chemistry between different septic system density groups was analyzed to understand how septic system usage impacts the water quality of the Yellow River Watershed located in Gwinnett County, Georgia. Seventy water samples were collected at baseflow conditions in the summer of 2006. The samples were analyzed for the abundance and distribution of chlorides, sulfates, nitrates, and specific conductance. Geographic Information Systems were used to determine sample collection sites, assign samples into density groups, and spatially analyze and display the results. Statistical methods were used to compare the results of each density group with all others,and to find any correlation of the anions with respect to specific conductance. Regression coefficient values between nitrate and specific conductance in all groups average 0.77 and the elevated nitrate concentrations in group four suggest a limited relationship between septic system density and baseflow water quality