Future developments in Bangladesh: urbanization scenarios to assess flood risk

In this research, a national-scale flood risk assessment for four scenarios up to 2100, has been applied to the country of Bangladesh. In order to make this assessment, population projections are made, making use of the four scenarios. Furthermore, an urban driver analysis has been conducted to quantify historical urbanization patterns. Then a land-use model has been altered to model population densities up to 2100 for the four scenarios, using the population projections and the results from the urban driver analysis. The output from the urbanization model is used in a flood impact model in combination with water depth maps, resulting in flood impact maps and tables for each of the four scenarios and for each decade up to 2100 at a resolution of 50x50 meters. This study suggests that future flood risk, without interventions, may increase with 18 – 65% in 2050, compared to the current situation, attributable to socio-economic change. Moreover, in the same period the population may increase with 13 – 52%, hence, the flood risk may increase disproportionally compared to the population growth. Furthermore, the in this study proposed policy interventions show that the increase in flood risk may better be mitigated by embanking nonprotected areas rather than improving already protected areas.