Estimación del exponente aplicable en la ecuación de transferencia de caudales, para la Región del Alto Magdalena en Colombia

Abstract

The discharge estimation in at ungaged site can be done through the discharge transfer method. This method, allows to transfer data from measurement stations from a gaged site to an ungaged site, provided these have homogeneous hydrological characteristics. The purpose of this report is to determine the applicable exponent in the discharge transfer equation, for a limited subregion for the Alto Magdalena basin, following the methodology established by the United States Geological Survey (USGS). To obtain the parameters of the model the historical records of peak discharge of 51 hydrometric stations distributed throughout the study region were used. The discharge values associated to different return periods (T = 2.33, 5, 10, 25, 50 and 100 years) were calculated through the empirical methodology of the USGS and the adjustment to probability distribution functions of the data series. The application of the calculated exponent was evaluated with the Cross Validation-Leave one out (LOO) test, the Nash-Sutcliffe coefficient (NS), the percent bias (PBIAS) and the mean percentage error (MPE). The model calibrated in the present report is shown as an acceptable option for the estimation of peak discharge in analysis region, for sites that are located on the same stream. The value of the exponent associated to the discharge transfer method that incurs in smaller errors of estimation for the described zone is 0.821.