Hazard Assessments of Riverbank Flooding and Backward Flows in Dike-Through Drainage Ditches during Moderate Frequent Flooding Events in the Ningxia Reach of the Upper Yellow River (NRYR)

Abstract

In this study, the riverbank inundation caused by moderate frequent flooding events (with recurrence periods of less than 20 years), along with the increasingly serious hazards of backward flows in dike-through drainage ditches in the Ningxia Reach of the upper Yellow River (NRYR), were investigated. Then, a comprehensive method for hazard assessment of the floodplains and backward flows in the NRYR was proposed, which fully integrated geographical information systems (GISs), remote sensing (RS), and a digital elevation model (DEM), as well as river dynamics theory. This study first established a one-dimensional unsteady hydrodynamic model for the NRYR. The historical flood hydrology observation from 2012, along with the aerial image measurement data of the study area, were used to calibrate and verify the accuracy of the model. The hazards of riverbank inundation and damages to water affected engineering facilities, as well as the backward flows of dike-through drainage ditches caused by the moderate frequent flooding events, were comprehensively analyzed. Also, this study configured the hazard map and proposed revisions to the flood hazard ranking regime definitions, and discussed the impacts and prevention and control measures of moderate frequent flood damages. The proposed method could effectively meet the hazard analysis demands of the moderate frequent flooding events in the NRYR. are widely used in the field of flood hazard analysis due to the rigorous approach. These abilities mainly include the applications of one-dimensional hydrodynamic models of river channels [4-8]; two-dimensional hydrodynamic models [2,[9][10][11][12][13][14][15]; one-and two-dimensional coupling models [16][17][18][19][20][21][22]; and three-dimensional hydrodynamic models [23][24][25][26][27][28]. In a previous related study, Anees et al. discussed the applicability and limitations of one-, two-, and three-dimensional numerical modeling techniques for flood analyses in river channels and floodplains [29]. With the rapid development of spatial information technology, such as geographic information systems (GISs), remote sensing (RS), and global positioning systems (GPSs), a large number of research studies have been recently carried out regarding the application of "3S" technology in flood inundation hazard assessments in river-floodplain areas. These have included flood inundation connectivity and evolution simulations of floodplains or surface flooding based on GIS and digital elevation model (DEM) technology [30][31][32][33][34][35][36][37][38]; flood hazard analyses and hazard graph mapping based on GIS and hydrodynamic numerical models [39][40][41][42][43][44][45][46][47][48]; and flood impact and loss evaluations based on 3S and DEM technology [49][50][51][52][53]. Meanwhile, some researchers have attempted to predict flood inundation hazards in large range or even global scales with low-resolution DEM data and hydrologic and hydrodynamic models [54][55][56][57][58].In recent years, the research team of the State Key Labora...

Review for Some Applications of Riverbanks Flood Models

“…Under the influence of annual increases in downstream sedimentation in the NRYR. The rise in recurring moderate flood levels resulted in greater frequency and higher risk of backflow According to the findings [18].…”

Accuracy and Reliability Analysis of Pipe Irrigation Metering Device for Sandy Water Source

“…Most of the agricultural irrigation water in Ningxia is obtained from the Yellow River. However, the Yellow River is a world famous natural muddy river with the highest sand concentration among the major rivers in the world [6,7].…”

Coupled modeling of bed deformation and stability analysis on a typical vulnerable zone on the Ningxia reach of the Yellow River during flood season

“…Damming and diversion are important human activities that affect the water and sediment conditions of the NRYR (Fan, Shi, Zhou, & Du, 2012; Fan, Wang, & Ran, 2010). The river channel possesses complex morphology, large mainstream swing, and erodible riverbanks in the NRYR (Tian, Ma, Yuan, Wang, & Yue, 2019; Yuan, Tian, Wang, Liu, & Chen, 2018). Flood disasters have occurred frequently throughout its history.…”