The above two case studies demonstrated how well the VEP-NLMM-L performs in the parameter calibration stage. However, the optimal parameters obtained by the RAGA have not been examined as to whether they are suitable for routing other different floods occurring in the same river reach. Thus, two flood events that occurred in the River Wye in December 1960 (Scenario I) and January 1969 (Scenario II) were used in this case to further validate the applicability and reliability of the VEP-NLMM-L. First, parameters of the VEP-NLMM-L (L = 4) for Scenario I were estimated. Then, the obtained parameters were applied to predict the outflow hydrograph for Scenario II. The optimal parameter vectors by optimizing the LMM and VEP-NLMM-L (L = 4) for Scenario I are listed in Table 6. The corresponding estimated outflows of Scenario I are shown in Figure 4.