How do households perceive flood-risk? The impact of flooding on the cost of accommodation in Dublin, Ireland

Abstract

Climate change and human behaviour, such as building on floodplains, are increasing the incidence of floods in urban areas. This paper investigates the relationship between flood risk and residential accommodation costs, both sales and rental, using a detailed dataset of over 650,000 sale and rental listings in Dublin, Ireland over the period 2006–2015. These are combined with detailed data for the Dodder river on 1% flood risk and past flooding events. Research to date suggested that the lack of a persistent effect may have an impact on buyers' and sellers' risk perceptions by changing with the prevalence of hazard events and that homebuyers are unaware of flood risks and insurance requirements when bidding on properties. Using hedonic regression techniques, the presented work shows opposite results: flood events are found to have a negative impact, particularly on sale prices, while being at 1% risk has no effect once past flood events are controlled for. For past flood events, however, there is evidence to suggest that this impacts on property values, certainly in the areas affected and up to 200 m away. Before the institutional flood risk maps were published, the assessment was based on existing Ordnance Survey maps which showed areas ‘Liable to flooding’ generated with land surveys carried out around the 1830. Set against these devices for raising awareness of flooding is the Irish constitution which regards property rights almost the same as human rights, which obvious impacts on the ability of planners to implement development/zoning plans. On the basis of this evidence, it is reasonable to conclude that households pay more attention to past flood events than to scientific assessments of flood risk, has important policy implications about communicating flood risk to consumers.