# Evaluation of Different Simulation Methods for Analyzing Flood Scenarios in the Danube Delta
## 5 Discussion
Figures 15 and 16 indicate that the areas flooded under the four flood stages in the static method, varied between 0.85 km\({}^{2}\)-1.76 km\({}^{2}\) (Partizani), 0.29 km\({}^{2}\)-0.54 km\({}^{2}\) (Ilganii de Sus), 0.11 km\({}^{2}\)-0.40 km\({}^{2}\) (Vulturu), 0.04 km\({}^{2}\)-0.20 km\({}^{2}\) (Maliuc), 0.11 km\({}^{2}\)-0.75 km\({}^{2}\) (Gorgova), 0.23 km\({}^{2}\)-0.86 km\({}^{2}\) (Mila 23), 0.08 km\({}^{2}\)-0.40 km\({}^{2}\) (Crisan), and 0.28 km\({}^{2}\)-1.60 km\({}^{2}\) (Sulina). Figure 15: The differences of flooded area for the analyzed scenarios by using static method and dynamic method at: (**a**)—Partizani, (**b**)—Ilganii de Sus, (**c**)—Vulturu, and (**d**)—Maliuc settlements. Referring to the first flood stage, the largest percentage differences between the two methods regarding the flooded area were observable for Vulturu (difference of 9.63%) and Maliuc (difference of 9.17%). The smallest percentage differences in the first flood stage were observable for Partizani (difference of 1.68%) and Gorgova (difference of 3.68%). For the second flood stage, the largest percentages, in terms of the differences regarding the flooded area, appeared in Ilganii de Sus (difference of 12.55%), Vulturu (difference of 16.85%), Maliuc (difference of 13.76%), and Crisan (difference of 10.44%), and the smallest difference was found in Mila 23 (difference of 4.30%). In the third flood stage, the largest percentage differences regarding the flooded area were recorded in the settlements of Crisan (difference of 21.89%) and Sulina (difference of 21.20%). At the same time, the smallest percentage differences were present in Partizani (difference of 9.46%), Ilganii de Sus (difference of 8.96%), Vulturu (difference of 9.63%), and Gorgova (difference of 9.83%). The dynamic method gives the lowest percentage of flooded areas for all the settlements. This is due to the fact that the dynamic method involves flooding the surfaces gradually, and depending on the topography of the terrain. Gradual surface flooding is induced by the flow of the river, and so the area flooded by considering the dynamic method at water levels such as those shown in flood stages II and III, was smaller than the area flooded by considering the static method. In addition to this fact, the physical-geographical factors had a certain influence on the process of flood leakage in the dynamic method. Here the relief influences the size, and especially the distribution, of the flood leakage by its degree of fragmentation and by the size of the slope of the land in the localities considered. If we analyze the evolution of the flood at all flood stages, in Figures 11 and 12 we can see that the flooded area increased sharply in the localities Vulturu (from 0.10 km\({}^{2}\) in flood stage II to 0.29 km\({}^{2}\) in flood stage III), and Maliuc (from 0.04 km\({}^{2}\) in flood stage III to 0.18 km\({}^{2}\) in flood stage IV). In the case of the settlements Partizani and Ilganii de Sus, the flooded area showed a constant increase in all flood stages. This was due to the fact that the land surface tends to a smoother slope compared to Vulturu and Maliuc settlements, where the slope in some areas becomes steep. At the same time there are other factors that influenced the process of flood leakage in the dynamic method, such as vegetation, which has an important role in the leakage process. On one hand by influencing the soil formation, and on the other hand contributing to increasing capacity of infiltration in the soil and reducing soil erosion. Another important factor is the land use. This essentially and negatively influences flood leakage conditions.