Chapter 51 Analysis of Public Perceptions on Urban Flood in Phnom Penh, Cambodia S. Heng, S. Ly, S. Chhem, and P. Kruy Abstract A remarkable population and economic growth has been seen in Phnom Penh, a center of commerce, tourism and residence. Urbanization in this capital city of Cambodia, changes of land cover from pervious to impervious areas, and the climate change phenomenon introducing a more intense rainfall within a short time, have led to frequent flooding during the rainy season. Human activities might be a main contributing factor to urban floods in this area. To propose a sustainable measure for such water-related hazard, understanding on public perception is one among various important issues to be considered. This study is aimed at analyzing public perceptions on urban flood in Phnom Penh. A questionnaire survey on 100 samples was conducted within four dense districts of the city. Key findings of the survey are: (1) flood depth of 0.15–0.30 m and flood duration of less than 1 h was very common since it is a rainfall-flood phenomenon, no overflow from rivers; (2) the impacts were greatly on small businesses and health of citizens; (3) most of the people did nothing when there are flood occurrences because flood water does not flow into their house; (4) garbage in the drainage system reduced the flood flow capacity; and (5) education on water engineering and effective garbage management were recommended by citizens to solve flood problems on a long term basis. These results might urge the government to take immediate actions on this extreme event. They also provide essential information for proposing a sustainable flood management strategy. Keywords Urban flood · Public perception · Phnom Penh 51.1 Introduction Urban flood has become a major risk to many cities globally. A consistent result from many studies shows that damages caused by urban floods is projected to increase in the future (Hammond et al. 2015). In recent years, such disaster brought a significant disruption to the city service and wide negative effects on citizens. For instance, S. Heng (B ) · S. Ly · S. Chhem · P. Kruy Institute of Technology of Cambodia, Phnom Penh, Cambodia © Springer Nature Switzerland AG 2021 M. Babel et al. (eds.), Water Security in Asia, Springer Water, https://doi.org/10.1007/978-3-319-54612-4_51 687