Study on prevention and control regionalization of flash flood threatened areas: Taking Yunnan Province as an example

Abstract

The flash flood disaster represents one of the most severe natural disasters in China, significantly impacting the country's social and economic development. From 2020 to 2022, the State Council conducted the first National Survey on Natural Disaster Risks, with a national general survey focusing on flood and drought disaster risks being a crucial component of this initiative. In accordance with the requirements of this survey, we utilized the calculation method ology outlined in “Technical Requirements for the Preparation of Flood Risk Regionalization and Prevention and Control Regionalization.” Building upon this foundation, we refined the calculation method for prevention and control zoning specifically within mountain flood threat areas. Utilizing data derived from the result of flash flood disaster investigation and evaluation, we calculated the prevention and control zoning for areas threatened by flash floods in Yunnan Province. The result indicate that key, medium, and general prevention and control zoning for flash floods in Yunnan account for 7.73%, 4.99%, and 87.28% of the total area respectively. Notably, the key prevention and control zoning for the flash flood are predominantly concentrated in central and northeastern regions of Yunnan Province. The zoning assessment of areas susceptible to flash flood disasters facilitates regional risk management strategies as well as targeted investigations into critical hidden dangers. Furthermore, the calculation method employed in this study allows for rapid iteration alongside updates from ongoing investigation and evaluation into flash flood disasters, thereby providing essential support for effective prevention and control measures across various locations.

Keywords

areas threatened by flash flood / prevention and control regionalization / the results of flash flood disaster investigation and evaluation / Yunnan Province