Flood and Residential Mobility in France

The evidence on whether people adapt to climate extreme events by moving out of vulnerable areas is currently mixed. In this article, we analyse residential mobility following floods using comprehensive French data. Our identification strategy consists in comparing individuals living in areas exposed to flood risk which were actually subject to a flood, with individuals also residing in flood risk areas but which were not subject to flood. Our results suggest that residential mobility increases by 1 percentage point in the two years following a flood. Compared to the baseline inter-municipality mobility rate in our sample, it equates to a 30% increase in the probability of moving out of the municipality of residence following a flood. The effects are strongly heterogeneous. Mobility rates following a flood are observed to be lower for the bottom and the top quintiles of equivalised disposable income than for the middle quintiles. The effects are found to be more pronounced for private renters than for home-owners and others. An analysis of aggregate flows at the municipality level reveals no effect of flooding on residential mobility on average, confirming the importance of using granular individual data. However, the data do suggest changes in the composition of population outflows. We observe a lower share of homeowners in the population outflows from municipalities that have flooded.