Abstract
WATER QUALITY IN RELATION TO STREAM FLOW IN THE RED RIVER BASIN
Steven W. Hamilton1
Gregory S. Ridenour2
Between June 1998 to August 2002 physical and chemical parameters were measured from locations in the Red River watershed. Water temperature, dissolved oxygen, and pH were measured in the field using multiparameter probes (Hydrolab and YSI). Parameters measured in the lab were totals alkalinity, calcium, hardness, nitrate-nitrite nitrogen, orthophosphate, total phosphorus and sulfate. While many of the samples were collected on tributaries of the Red River, six were collected from the Red River at Port Royal where a USGS stream flow gauging station is located. These data are analyzed for this study. The parameters were associated with a stream flow value by downloading flow values and dates from the USGS National Water Information System and matching them with the dates of our samples. A flow duration curve was constructed using software developed by Bruce Cleland of America’s Clean Water Association to display the percentage of time that a given flow is equaled or exceeded. Flows were divided into five regimes (high, moist, mid-range, dry, and low) whose midpoints are 5%, 25%, 50%, 75%, and 95%, respectively. Only total alkalinity showed a significant correlation with flow at the 5% significance level. Calcium was just outside the 10% significance level. Perhaps the lack of correlation between flow and the other parameters resulted from sampling at primarily low to dry flow conditions. Collection of data over a wider range of flows should be attempted to better elucidate the relationship between discharge and nutrient concentrations and other physicochemical parameter in this watershed.
1 Professor, Center for Field Biology, Austin Peay State University, Clarksville, TN 37044, hamiltonSW@apsu.edu
2 Associate Professor, Geosciences Program, Austin Peay State University, Clarksville, TN 37044, ridenourg@apsu.edu
Charts & Tables
Pollutant Levels vs. Discharge at Red River, below Port Royal