Assessing Climate Change Impacts on Flooding Risk in the Acelhuate River Channel Slums with the d4PDF Database in El Salvador

Abstract

This research explored the effects of climate change on extreme river levels in San Salvador, El Salvador's capital. The city faces significant challenges with informal settlements resulting from rural-urban migration, with 792 slums housing 32% of the population, many situated within river channels. In 2020, two major tropical storms caused substantial damage, particularly to these vulnerable settlements. This study focused on a previously unexamined basin, utilizing future climate simulations spanning from 2051 to 2111, with a 4K increase in global temperatures relative to preindustrial levels, to extract extreme precipitation events. A hydraulic and hydrological model was employed to simulate future extreme river flow levels. Four slum locations were assessed for flood risk based on their altitude within the river channel and modeled water levels, comparing these projections to the 2020 storm impacts. Three slums are expected to have a significant increase in flooding risk in the late 21^st century.