Evaluating the cumulative costs of small-scale flash floods in Kuala Lumpur, Malaysia

Abstract

• Damages and losses due to small-scale flash floods are evaluated. • A heuristic approach was used to overcome data scarcity. • Indirect damage costs are nearly-four times higher than direct damages. • Disaster loss due to flash floods will be significant in the future. The cumulative costs associated with frequent small-scale flash floods have been calculated for Kuala Lumpur, Malaysia, to get an insight on damages and losses. There is limited information on the impact of frequently occurring small-scale events compared to large-scale or catastrophic disasters, particularly with respect to its overall implications on the economy at the city level. Such information would support the formulation of effective disaster risk reduction strategies. The study evaluated the direct and indirect damage cost of 204 flash floods in Kuala Lumpur between 2010 and 2016 using a heuristic approach to compensate for data scarcity, and drawing on the market price and restoration cost method. The assessment relied primarily on secondary data from various government departments and relevant authorities. The results revealed that the total flash flood damage was as high as RM48.7 million, which represented 0.04% of the gross domestic product (GDP) of Kuala Lumpur in 2016. Direct costs were associated with damage to roads as well as commercial and residential areas to a lesser extent, while loss of productive time was the leading factor for indirect costs. Indirect damage costs are up to four times higher than direct damages, with disrupted road networks being the highest contributor to both costs. Moving forward, risk reduction strategies should focus the transportation sector. The findings of this study is useful baseline information for future projection of damages and losses due to small-scale flash floods in Kuala Lumpur.