HOW RAINFALL AFFECTS THE TURBIDITY AND NUTRIENTS OF THE LITTLE TALLAPOOSA RIVER AND CENTRAL CAMPUS BRANCH, CARROLL COUNTY, GEORGIA

Water quality testing of the Little Tallapoosa River and Central Campus Branch began in August 2004. The Little Tallapoosa River is the trunk stream that drains the area, and Central Campus Branch is a tributary to the river that drains much of the campus of the University of West Georgia. The Little Tallapoosa River serves as a major source of drinking water for the city of Carrollton. The watershed is a mix of farmland, forest, small towns, and light industry. In the recent years, the area has undergone much development including the construction of subdivisions, roads, parking lots, and shopping complexes. The river flows through the city of Carrollton before reaching the campus. Central Campus Branch watershed is extensively developed with buildings, parking lots, roads, side walks, lawns, and recreation fields. One sample site is at a weir on Central Campus Branch near its confluence with the river. Except after heavy rains the river is sampled downstream of the confluence with Central Campus Branch. Sampling was done up to five days a week for four months. Measured in the field were turbidity, pH, specific conductivity, dissolved oxygen, and flow. Samples were collected and analyzed for nitrite-nitrate-N and total phosphorus. Remnants of two hurricanes passed through the area during September. Tropical storm Frances produced 4.2 inches of rain on September 7, 2004 and Ivan’s rainfall on September 16, 2004 was 3.66 inches. These storms greatly increased turbidity reaching 240 and 75 NTU in Campus Branch and the river, respectively. Specific conductivity and pH were lowest after the heavy rains. The range of nitrite-nitrate-N was 0.13 to 1.4 mg/L and 0.18 to 1.55 mg/L for the Little Tallapoosa River and Central Campus Branch, respectively. The creek averages 0.9 mg/L nitrite-nitrate-N while the river averages 0.3 mg/L. The highest total phosphorus was 0.22 mg/L for Central Campus Branch and 0.34 mg/L for the Little Tallapoosa River. Because of flooding after large rain events we were unable to sample and determine the relationships between rainfall and nutrients.