PEAK FLOW-RATE AND RECESSION-CURVE CHARACTERISTICS OF A KARST SPRING IN THE INNER BLUEGRASS, CENTRAL KENTUCKY

The flow rate at the terminal spring of a 1929 ha karst ground-water catchment has been continuously monitored for 2 years, and 108 identifiable events were analyzed. The peak flow rates followed a beta frequency distribution with parameters alpha = 0.365 and gamma = 1.135. Events were separated into high-flow and low-flow. High-flow events had characteristics attributable to pipe flow. Correlation and stepwise regression were used to develop peak flow rate prediction equations for the combined 108 events and for the 81 low-flow events. The portion of the recession curve identified as pipe flow was a watershed constant and time invariant. The base flow was seasonal, increasing in the winter to approximately 0.071 m3 s-1 and decreasing in the summer to approximately 0.014 m3 s-1.