URBAN DEVELOPMENT VS. WATER QUALITY: A COMPARISON OF FLOW IN RELATIONSHIP TO TURBIDITY, RAINFALL, NUTRIENTS, FECAL COLIFORM, AND WATERSHED COVER IN WEST GEORIA

Atlanta Georgia is one of the fastest growing cities in the United States. Due to urban sprawl the watersheds around the greater Atlanta area are experiencing environmental stresses that affect the water quality. In the west Georgia road construction, housing developments, increased water withdrawals, treated sewage discharge, and farming are contributing to potential water quality problem. Turbidity, fecal coliform bacteria, and nutrients are good indicators of drinking water quality and the ability of a watershed to support life. We are monitoring the Tallapoosa River, the Little Tallapoosa River, the Chattahoochee River and a small creek on the campus of the University of West Georgia (Central Campus Branch). Our research compares the relationship between turbidity, nutrients, fecal coliform and flow. With two years of data we will estimate how long it will take drinking water reservoirs in west Georgia to fill up with sediment.

The four sites have been sampled for one year. The sample sites are tested for turbidity up to 5 days a week in 12 to 24 hour intervals. Results show that turbidity is very sensitive to rain events and flow. Turbidity increases is also based on the intensity of the rainfall. Basin size has a direct effect on recovery time after a rain event, with small basins recovering quicker than large basins. Weekly sites are tested for Nitrate-Nitrite-N and Total Phosphorus. Minimum, median, and maximum values for N-N-N are: Tallapoosa (CTW-105) 0.13, 0.23, 0.48mg/L, Little Tallapoosa (CCW-104) 0.30, 1.20, 1.94mg/L, and Chattahoochee (CCM-101) 0.24, 1.06, 2.26mg/L. The phosphorus values are: CTW-105=0, 0.29, 1.33 mg/L, CCW-104=0, 0.16, 0.85 mg/L, and CCM-101=0.5, 0.21, 0.38mg/L. Results show that nutrient levels are a direct effect of land use. By sampling for fecal coliform 3 days a week we plan to determine the relationship between land use, turbidity, flow, rainfall, and fecal coliform colonies. Early results are CTW-105=390, 1100, 2500 colonies/dL, CCW-104=99, 1100, 2700 colonies/dL, CCM-101=50, 120, 230 colonies/dL, and the Tallapoosa =0, 140, 410 colonies/dL. The Little Tallapoosa River, which runs through Carrollton, GA, usually has the highest fecal count compared to our other sites. The sample sites on the Tallapoosa River and the Chattahoochee River are located in more rural areas.