On the Relationship between Urban Inundation and Rainfall Amount in Guangzhou and Associated Thresholds
YANG Hui-yan
WANG Ting
GAO Mei-tan
WU Jian-ling
LI Li-wei
Abstract：Based on the reports and data of urban inundation as well as rainfall observations in Guang-zhou from 2010 to 2022,this paper used the methods of linear regression analysis and probability density sta-tistics to study the relationship between the metropolitan's urban inundation and rainfall intensity and accu-mulated rainfall amount,and determined the thresholds of rainfall amount for urban inundation caused by heavy rain.The results are shown as follows.The seriousness of urban inundation is closely correlated with 1-h rainfall intensity and 2-h accumulated rainfall amount.Based on the severity of urban inundation for dif-ferent road types(i.e.,culverts,tunnels,interchanges,municipal roads,inner lanes and residential are-as),the risk of urban inundation was classified into four categories according to a risk level classification standard for urbanized places.Using historical records of urban inundation,this work determined rainfall a-mount thresholds for different road types during both high and low tidal levels.Then,the observed inunda-tion processes for 2022 were used to verify the thresholds.It was shown that as much as 50％of the pre-warned levels of urban inundation are consistent with the observed ones,and up to 67％of the former is only one level of severity apart from the latter,and effective pre-warnings can be made 0.5 to 2 h prior to the ac-tual incidence.
Keywords：urban inundationrainfall intensityaccumulated rainfall amountthresholdGuangzhou
Publication Date：2023-12-20
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 23-28 )