An economic assessment of urban flooding in Cambodia: A case study of Phnom Penh

In development discourse, ‘sustainability’ is defined as a balance between the environmental, economic and social aspects of a scenario. Economic assessments of the value of natural environments within and surrounding cities, in terms of the ecosystem services they provide, are important for understanding the nature of sustainable development in emerging economies. Ecosystem services play a vital role, providing resources for economic development, regulating environmental flows, supporting livelihoods and well-being, and representing of cultural values such as spiritual or recreational benefits. However, to date, ecosystem services have generally been overlooked in terms of planning and policy decisions in Cambodia. More specifically, in Phnom Penh, the role of wetland ecosystems in retaining stormwater flows for flood protection has not been sufficiently recognized. However, determining the value of urban wetlands in mitigating the impacts of flood events in heavily populated urban areas is complex and difficult to conceptualize. This study assesses this value in terms of the regulating ecosystem services they provide. It achieves this by placing a value on the economic losses experienced in three study areas in Phnom Penh that experience regular rainy season flooding. A mixed methods approach was used to collect the required data for this analysis from 300 questionnaire respondents, as well as through interviews with key informants. The results show that urban flooding is primarily caused by heavy storm events during the rainy season. Economic losses related to these flood events include: vehicle lubricant and other vehicle maintenance, disruption to business activities, and flood recovery costs. Notwithstanding this, the level of flood preparedness by Phnom Penh citizens was found to be very low. These findings suggest that development planners and policymakers should consider urban planning approaches that place a value on the degradation of urban wetlands to mitigate future economic losses from unsustainable development.