Warnell School of Forestry and Natural Resources, The University of Georgia
Abstract
Proceedings of the 2011 Georgia Water Resources Conference, April 11, 12, and 13, 2011, Athens, Georgia.Since its inception in the 1950s, worldwide adoption and use of the Curve Number (CN) methodology for estimating runoff has highlighted some inconsistencies, limitations and problems. Analysis of curve numbers derived from 34 years of rainfall-runoff data, gathered from a 2.7 ha Georgia Piedmont catchment managed under no-till, showed that the average CN (57) that led to mean runoff estimate matching the mean measured runoff was 16 less than the average of the range of CN values (73) given in standard handbook tables for the catchment. The derived median value of the initial abstraction ratio (λ) was 0.04, compared to 0.2, the standard value. Many researchers recommend 0.05 for λ. Use of standard CN coefficients and values for fields managed in no-till, and possibly other conservation tillage systems, would likely lead to overestimation of runoff.Sponsored by:
Georgia Environmental Protection Division
U.S. Geological Survey, Georgia Water Science Center
U.S. Department of Agriculture, Natural Resources Conservation Service
Georgia Institute of Technology, Georgia Water Resources Institute
The University of Georgia, Water Resources FacultyThis book was published by Warnell School of Forestry and Natural Resources, The University of Georgia, Athens, Georgia 30602-2152. The views and statements advanced in this publication are solely those of the authors and do not represent official views or policies of The University of Georgia, the U.S. Geological Survey, the Georgia Water Research Institute as authorized by the Water Research Institutes Authorization Act of 1990 (P.L. 101-307) or the other conference sponsors
