260-8 Designing Predictive Natural Hazard Models for Freetown, Sierra Leone

Session: Advances in Geospatial Applications for Environmental and Engineering Geology (Posters)

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Abstract:

The Freetown Peninsula, located in the Western Area of Sierra Leone, is the capital city of Sierra Leone and is a major port city on the Atlantic Ocean. Freetown is the largest city of Sierra Leone, home to roughly 15% of the country’s total residents. An increase in informal settlements and deforestation related to rapid urbanization has raised concerns for sustainable urban development and natural resource management. In 2017, the Regent-Lumley landslide initiated upslope from a construction zone and traveled 6 km to Freetown’s coastline. This rainfall-triggered landslide resulted in 1,141 people declared dead or missing and the loss of homes for over 3,000 people. Characterized by coastal wetlands and steep-sloped mountains, Freetown has become increasingly vulnerable to natural hazards like the Regent-Lumley landslide; these hazards have been intensified by climate change. Using GIS software including QGIS, ArcGIS, and Google Earth Engine, we aim to predict high risk areas for diverse natural hazards in Freetown: landslides, flooding, and coastal erosion, among others. Using historical records, current climatic data, and environmental factors including land-use, geological, and vegetation information, we will model the potential impact locations across spatial and temporal scales. Crucially, this hazard information will be hosted on a web portal associated with the city government of Sierra Leone, allowing urban and resource management officials to mitigate the destructive impacts of climate change on this historic city. This research builds on the approach taken by The World Bank, which published a series of reports detailing Freetown’s hazard and risk assessment in 2019. By updating high risk natural hazard locations for 2025 and beyond, while building models that allow for the input of data from any year, stakeholders can better prioritize conservation and reforestation efforts across Freetown. 

Geological Society of America Abstracts with Programs. Vol. 57, No. 6, 2025

doi: 10.1130/abs/2025AM-10379

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