## 1 Introduction  
With the high pace of urban environment development, many cities worldwide face risks from urban floods, which is evolving as a major threat to life and property. According to the statistics of the World Meteorological Organization (WMO), around 7870 hydrometeorological disasters occurred in the world from 1970 to 2016. These floods have resulted in 1.86 million deaths and an economic loss of USD 1.9 trillion [1]. Chinese cities are no exception in this regard. Based on the available statistics, more than 400 Chinese cities with a wide geographical distribution were affected by floods from 2007 to 2018. These flood-related disasters have claimed 21,720 lives and resulted in a staggering economic loss of CNY 3163.9 billion [2, 3] (p. 57; pp. 661-662). The problem of floods has greatly affected safe operations in cities, disrupted normal life, and has become a matter of serious concern. Flood-related disasters have become a severe impediment to the high-quality development of cities in China [4]. Urban waterlogging disaster is an extremely complex engineering problem with many dimensions [5, 6, 7, 8, 9] (pp. 1-2; pp. 661-662). The processes that lead to such urban disasters are interactive and complicated, involving many natural and human-induced factors. They can be understood only by understanding the state of natural systems, social conditions, and developmental activities [10, 11, 12, 13, 14, 15]. Experts and scholars worldwide have been exploring ways to prevent and control flood disasters. They have put forward many suggestionsbased on ground conditions and theoretical methods that can be used effectively for flood control. Researchers and engineers based in China are constantly engaged in developing flood control strategies; they have also learned techniques practiced in foreign countries, which they successfully adapt for effective flood control [16; 17; 18; 19; 20; 21; 22]. In the face of the rapid development of cities built on regions of diverse geological environments, climatic zoning, and other conditions, preventing and controlling urban floods are challenging. However, after decades of continuous exploration, China has successfully developed a suitable strategy to manage and mitigate urban flood disasters. It has been proposed that by 2025, China will build a \"sixteen-character\" urban flood control and drainage system. This system works on a combination of parameters such as source emission reduction, well-designed storage and drainage facilities, risk elimination, and emergency response if stipulated standards are exceeded. Together, various elements of this system significantly improve the urban drainage system and effectively prevent waterlogging and flooding [23]. Fundamentally, the \"sixteen-character\" strategy aims at an efficient disposal capacity by building artificial reservoirs and lakes to improve flood detention and storage. Laying water pipelines, dredging rivers to improve flood discharge, and building sponge cities to enhance urban rainwater flood infiltration and storage are the other steps suggested to prevent flooding. On the mitigation front, steps are taken for emergency flood discharge, evacuation of residents, providing emergency aid, transportation of materials and implementation of traffic control. Undoubtedly, these measures have played a vital role in urban flood control in China. However, in the face of pervasive floods that are becoming more and more severe and seriously restricting the high-quality development of its cities, there is a need to develop innovative ideas and theoretical and practical methods for more effective solutions. So, in this study, we use the rainfall during the \"720\" torrential rainstorm (in three days, from 17 to 20 July 2021, Zhengzhou received 617.1 mm of rainfall. On 19 July alone, the rainfall was 552.5 mm. This torrential rain disaster flooded all the urban areas of Zhengzhou and paralyzed the city's traffic. More than 2000 roads were damaged, and many infrastructure facilities were destroyed.