Identification of flood vulnerability for an effective flood-prone zone mapping in Kuala Lumpur city

Abstract

Kuala Lumpur city has suffered from higher occurrences of flash flood due to the rising numbers of rainfall frequencies resulting from the rapid urban development and climate changes, namely the Urban Heat Island (UHI) effect. It has imposed various threatening impacts on the city and its dwellers. Hence, the flood vulnerability needs to be well-observed so that the flood-prone zone mapping in Kuala Lumpur city can be accomplished. The assessment of flood-prone zone mapping is essential as it is a significant element in developing a flood resilience city. Therefore, systematic flood management initiatives can be constructed and be implemented throughout city planning and development. This study aims to establish a flood-prone zone mapping in Kuala Lumpur city by evaluating the flood vulnerability of the city. A critical assessment of literary works is undertaken to identify the direct and indirect impacts of the flash flood in Kuala Lumpur city. Afterwards, a questionnaire form is distributed among the target respondents to verify the findings accumulated through the literature review. Meanwhile, the flood vulnerability is assessed by analysing the daily rainfall data collected from twenty rainfall stations in Kuala Lumpur between 1970 and 2019, which are retrieved from the Department of Irrigation and Drainage (DID). The daily rainfall data is then analysed using the Standardised Precipitation Index (SPI) at a 3-month (SPI-3) time scale. The frequency of the extremely wet and severely wet occasions is used to propose the flood-prone zone mapping. The components and indicators affected by the flash floods are discovered, and the flood vulnerability for each constituency are illustrated to offer an effective flood-prone zone mapping. Adopting and considering the flood-prone zone mapping into various flood management initiatives will reduce the risk and impacts of the flash flood to the urban landscape. Implementing this approach would contribute to a vision of a flood resilience city in Kuala Lumpur city and consequently, improve the quality of life.