Effective discharge is defined as the discharge responsible for carrying the most sediment over a significant period of time (e.g., 20 years). As such, it is often thought to be the discharge that drives the average morphologic response of a river, i.e. the dominant discharge. The objective of our study is to compare the effective discharge calculated with standard methods, along with another potential measure of the dominant discharge known as the half-load discharge, to that obtained from the solution of the 1D morphodynamic model based on the work of Bolla Pittaluga et al. (2014). To accomplish this we compare the effective discharge of Lanzoni et al. (2015), obtained with this new method applied to a large reach on the Po River, to calculations made using the standard effective discharge and the sediment half-load discharge. Results show that the classic effective discharge calculations underestimate the dominant discharge obtained through morphodynamic modeling by a factor of 2; whereas the half-load discharges provide estimates of the dominate discharge that are in line with the modeling analysis. Comparison of the three measures of the dominant discharge show that all methods yield statistics that are significantly lower than typical flow statistics used to estimate the dominate discharge for this section of the Po River.