Blue-green strategies for flood and drought mitigation in urban areas

The fast-growing urbanization and climate change lead to increasing urban flooding. To mitigate the negative impacts of these trends, several types of solutions exist including blue-green adaptation strategies. This study will investigate the impact of extreme rainfall on urban flooding and evaluate the positive impacts of the blue-green strategies. Various types of local rainfall data from rain gauges, rainfall radar and crowdsourcing weather data platforms will be considered and combined to come up with the best estimates of the extreme rainfall above the urban study area. Based on that rainfall input, urban flooding will be simulated by means of a detailed urban flood model that considers the underground sewer network and the above-ground surface runoff and inundations. The simulation results will be validated for recent historical flood events. Thereafter, the impact of climate scenarios will be studied and blue-green strategies such as green roofs, rainwater storage and infiltration, wadis, etc. implemented to investigate the added value of these strategies as climate adaptation solutions.