Performance of Different Models for Curve Number Estimation (Case study: Bar Watershed in Khorasan Razavi Province, Iran)

Among different models for runoff estimation in watershed management, the Soil Conservation Services-Curve Number (SCS-CN) method along with its modifications have been widely applied to ungauged watersheds because of quickly and more accurate estimation of surface runoff. This approach has been widely accepted by hydrologists, water resources planners, foresters, and engineers, as well. Therefore, this work was aimed to estimate the curve number using CN-values through several methods viz. SCS, Sobhani (۱۹۷۵), Hawkins et al. (۱۹۸۵), Chow et al. (۱۹۸۸), Neitsch et al. (۲۰۰۲) and Mishra et al. (۲۰۰۸) in Bar Watershed, Iran. According to the results, the Neitsch formula showed the best performance for estimating the Curve Number in situation with low (CNI) and high (CNIII) antecedent moisture conditions. However, the weakest performance was related to Mishra (۲۰۰۸) in CNI and CNIII-conversions. The weakest performance was resulted from the exponential form of the Neitsch et al. formula and the variable meteorological conditions of the Bar Watershed over the year.

کلیدواژه ها:

Antecedent soil moisture ، Flood estimation ، North-Eastern Iran ، Rainfall-runoff modeling