Reestablish of flood disaster chronology and analysis of the flood control standard in Xiong’an New Area

Abstract

<p indent="0mm">The Xiong’an New Area is planned adjacent to the Baiyangdian Lake, which is considered the Pearl of North China. The lake lays a landscape and ecological environment foundation for the construction of a new city with blue water and green trees. However, as a lake at the bottom of historical “Nine Rivers”, the rainfall runoff in the Baiyangdian Lake basin is characterized by a large confluence area, a short flow path, and a concentrated confluence time. These characteristics exert tremendous strain on flood control in the Baiyangdian Lake basin. Floods have occurred frequently in the Baiyangdian Lake basin throughout history. This paper collected and sorted historical records of floods between 1470 and 2020 in Xiong’an New Area (Anxin, Xiongxian, and Rongcheng), used modern precipitation data, combined the precipitation grading formula of <italic>Atlas of Drought and Flood Distribution in China in Recent 500 Years</italic>, established the flood disaster grading sequence of Xiong’an New Area from 1470 to 2020, and analyzed the representative of the flood control standards. During the study period, 240 floods occurred in the study area from 1470 to 2020, with an average occurrence of <sc>2.3 a,</sc> floods of grades 4, 3, 2, and 1 occurred 7, 31, 85, and 117 times, respectively. However, the frequency and intensity of floods in the past <sc>50 years</sc> have reduced. In terms of spatial distribution, any flood will inevitably flood the lake area near the river. Even with a grade 4 flood, the northern and northwestern parts of Rongcheng and the northern and central parts of Xiongxian were not flooded owing to the high terrain and distance from the river. The recorded grade 4 extreme floods exceed the Daqing River’s “once in 50 years” flood standard. Given the trend of future climate warming and the re-humidification of North China, it is necessary to investigate whether the flood control standards and measures established during the drought period will be able to withstand further extreme floods.