Exploring the Relationships between Impervious Surface Percentage and Frequency of Urban Waterlogging: A Case Study in Hanoi, Vietnam

Abstract

In developing countries, rapid urbanization reduces the natural land area and increases the impervious surface. At the same time, urban rainstorm waterlogging is also becoming more frequent and serious. Therefore, one of the important works to be done is to elucidate the relationship between impervious surface expansion and waterlogging frequency (WF) causes of urban waterlogging. To move forward, we used ENVI to classify land cover types and applied the spatial analysis methods integrated in ArcGIS with internet open data to explore these relationships in Hanoi, Vietnam in 2018. The results show that waterlogging frequency was positively related to impervious surface percentage (ISP), indicating that if the median values of ISP increased then the waterlogging frequency would increase as well with a confidence level of 63.2%. This study demonstrates the importance for controlling the impervious surface expansion in urban waterlogging risk management and urban planning.

Assessment of the Susceptibility of Urban Flooding Using GIS with an Analytical Hierarchy Process in Hanoi, Vietnam

“…According to on-site surveys in the 12 central districts, flood-prone areas often coincide with major intersections or are densely populated zones. They are characterized by high impervious surface coverage and the flooding is exacerbated by antiquated drainage systems [84]. This impedes water infiltration into the soil, resulting in surface runoff during heavy rainfall events.…”