GIS-based multi-criteria modelling of flood risk susceptibility in Port Louis, Mauritius: Towards resilient flood management

Economic growth and population expansion in Mauritius have driven unprecedented rates of development. Most notably, increased urbanization of flood-prone regions has exacerbated challenges around resilience and vulnerability to recurrent flooding. We implement a multi criteria model consisting of a physical-oriented, a social-oriented and an economic-oriented scenario to identify highly vulnerable sites to flooding in the capital city, Port Louis. Social, technical, economic and legal perspectives are incorporated to propose comprehensive flood management strategies. The aim is to minimize the physical impacts of floods while also addressing the broader social and economic risks. Location-based flood management strategies are thereafter proposed to increase the resilience of the city to flooding. Measures include, inter alia, the construction of an underground stormwater storage tank at Champ de Mars, establishment of flood refugee camps at Valle acute accent e Pitot and Cite acute accent La Cure, reviewing building regulations and urban planning, replacement of the Caudan Underpass by an Overhead Bridge, green renaturing of rivers in downstream areas, construction of a retention pond on the downhill slope of the mountain at Bell Village, and the setting up of a diversion tunnel linking St Louis River to Grand River North West. The approach adopted will allow an understanding of the geography of flooding in Port Louis and support management decisions for limiting its impacts.

Automated summary

The economic growth and population expansion in Mauritius have led to increased urbanization and flooding challenges. Through a multi criteria model, comprehensive flood management strategies are proposed to minimize the physical impacts of floods while addressing the broader social and economic risks.