The curve number method is a universally accepted and widely explored model in the last four decades which is used to estimate event-based surface runoff. Its simplicity and versatility have made it popular, and the basic equation is used as an important part of various hydrological models. In the development of the SCS-CN model, various advanced and more data-intensive models were developed. These different versions introduced new parameters, but it cannot be applied directly in approximating real situations. To overcome these problems, this study has proposed two simple SCS-CN event-based runoff models. The two simple versions of the SCS-CN model (M1) are presented by taking initial abstraction as a function of P (Ia = αP) instead of S (M2) and by incorporating P5 in the fractional form to obviate undesirable sudden jump (M3). The performance of existing M1 and formulated M2 and M3 models has been compared using root mean square error (RMSE), Nash–Sutcliffe efficiency (NSE), PBIAS statistics, and ranking and grading system. Based on their ranking score for M2 and M3, model scores were significantly higher than the M1 model. Based on all statistics criteria and r2 value, both M2 and M3 models performed significantly well over the existing model.
Examining Curve Number-Based Modified Models for Runoff Estimation
Lecture Notes in Civil Engineering
International Conference on Hydraulics, Water Resources and Coastal Engineering ; 2021 December 23, 2021 - December 25, 2021
2023-05-01
10 pages
Article/Chapter (Book)
Electronic Resource
English
Runoff Curve Number: Has it Reached Maturity? Victor M. Ponce and Richard H. Hawkins
British Library Online Contents | 1997
|Curve Number Estimation of Ungauged Catchments considering Characteristics of Rainfall and Catchment
Online Contents | 2019
|Curve Number Estimation of Ungauged Catchments considering Characteristics of Rainfall and Catchment
Springer Verlag | 2019
|