Influence of rain pattern on flood control in mountain creek areas: a case study of northern Zhejiang

Abstract

Mountain creek areas are a type of flood-prone area, and the flood control in these areas has not been well understood. This study aims to evaluate the impact of rain patterns on the water level and the establishment of flood control standard in mountain creek areas by conducting a case study. The case study was performed on a typical mountain creek area, called Shiliqu watershed in Hangzhou, China. A MIKE11 model was first established to analyze the required flood control standard through investigating the river level impacted by two rain patterns (the designed rainstorm and the typhoon Fitow). The results show that the designed rainstorm pattern and the typhoon Fitow rain pattern have the single-peak and multi-peak profile, respectively. The peak rainfall value of the designed rainstorm pattern is much higher than that of the typhoon Fitow. However, the large fluctuations under the typhoon Fitow rain pattern causes multi-level overtopping which threats the safety of the flood control. Also, the typhoon Fitow could have a greater influence on the water level of the tributaries of the river than that of the mainstream. The selection of rain pattern on the design of flood control standard in mountain creek areas is discussed.

Water Level Prediction Using Different Numbers of Time Series Data Based on Chaos Approach

“…This clearly shows that the same values of parameter τ and m used in prediction may contribute to the same value of CC. Meanwhile, the value of CC exceeded 0.9400 for SD4000, SD5000 and SD6000 with the parameter combinations of (24,7), (22,6) and (18,5), respectively. This shows that the different amount of data used gives different prediction values.…”

“…Cao, Tao, Dong and Li [5] asserted that floods occur when excessive water level rises in river areas, whether in natural or man-made conditions. From a scientific vocabulary point of view, floods are caused by the existence of excessive heavy rain that cannot be supported by the river basin and thus the water overflows to the riverbanks or floodplains [18].…”

Flood Susceptibility Assessment with Random Sampling Strategy in Ensemble Learning (RF and XGBoost)

“…Land use categories provide insights into hydrological characteristics, such as infiltration and roughness at the watersoil interface, influencing the dynamics of flood movement [11]. With the advancement of computer capabilities and parallel computing technologies, it is now possible to use distributed hydrological and hydraulic models for precise calculations of flood movements in mountainous urban areas at a watershed scale [12][13][14]. These models, however, show varying degrees of accuracy in mountainous terrains compared to plains [15], and specialized models have been developed for watershed-scale mountainous urban areas to better represent the complex causes of flood disasters in these regions [16,17].…”